To Örebro University

A broad spectrum of novel targeted therapies with prime antitumor activity and/or ample control of hormonal symptoms together with an overall acceptable safety profile have emerged for patients with metastatic neuroendocrine neoplasms (NENs). In this systematic review and quantitative meta-analysis, the PubMed, EMBASE, Cochrane Central Register of Controlled Trials and clinicaltrials.gov databases were searched to assess and compare the safety profile of NEN treatments with special focus on the cardiovascular adverse effects of biotherapy and molecular targeted therapies (MTTs). Quality/risk of bias were assessed using GRADE criteria. Placebo-controlled randomized clinical trials (RCTs) in patients with metastatic NENs, including medullary thyroid cancer (MTC) were included. A total of 3695 articles and 122 clinical trials registered in clinicaltrials.gov were screened. We included sixteen relevant RCTs comprising 3408 unique patients assigned to different treatments compared with placebo. All the included studies had a low risk of bias. We identified four drug therapies for NENs with eligible placebo-controlled RCTs: somatostatin analogs (SSAs), tryptophan hydroxylase (TPH) inhibitors, mTOR inhibitors and tyrosine kinase inhibitors (TKI). Grade 3 and 4 adverse effects (AE) were more often encountered in patients treated with mTOR inhibitors and TKI (odds ratio [OR]: 2.42, 95% CI: 1.87-3.12 and OR: 3.41, 95% CI: 1.46-7.96, respectively) as compared to SSAs (OR:0.77, 95% CI: 0.47-1.27) and TPH inhibitors (OR:0.77, 95% CI: 0.35-1.69). MTOR inhibitors had the highest risk for serious cardiac AE (OR:3.28, 95% CI: 1.66-6.48) followed by TKIs (OR:1.51, 95% CI: 0.59-3.83). Serious vascular AE were more often encountered in NEN patients treated with mTOR inhibitors (OR: 1.72, 95% CI: 0.64-4.64) and TKIs (OR:1.64, 95% CI: 0.35-7.78). Finally, patients on TKIs were at higher risk for new-onset or exacerbation of pre-existing hypertension (OR:3.31, 95% CI: 1.87-5.86). In conclusion, SSAs and TPH inhibitors appear to be safer as compared to mTOR inhibitors and TKIs with regards to their overall toxicity profile, and cardiovascular toxicities in particular. Special consideration should be given to a patient-tailored approach with anticipated toxicities of targeted NEN treatments together with assessment of cardiovascular comorbidities, assisting clinicians in treatment selection and early recognition/management of cardiovascular toxicities. This approach could improve patient compliance and preserve cardiovascular health and overall quality of life.

The role of 18F-FDG PET in patients with variable grades of neuroendocrine tumors (NETs) prior to peptide receptor radionuclide therapy (PRRT) has not been adequately elucidated. We aimed to evaluate the impact of 18F-FDG PET status on disease control rate (DCR), progression-free survival (PFS), and overall survival (OS) in neuroendocrine tumor (NET) patients receiving PRRT. We searched the MEDLINE, Embase, Cochrane Library, and Web of Science databases up to July 2020 and used the Newcastle-Ottawa scale (NOS) criteria to assess quality/risk of bias. A total of 5091 articles were screened. In 12 studies, 1492 unique patients with NETs of different origins were included. The DCR for patients with negative 18F-FDG PET status prior to PRRT initiation was 91.9%, compared to 74.2% in patients with positive 18F-FDG PET status (random effects odds ratio (OR): 4.85; 95% CI: 2.27–10.36). Adjusted analysis of pooled hazard ratios (HRs) confirmed longer PFS and OS in NET patients receiving PRRT with negative 18F-FDG PET (random effects HR:2.45; 95%CIs: 1.48–4.04 and HR:2.25; 95% CIs:1.55–3.28, respectively). In conclusion, 18F-FDG PET imaging prior to PRRT administration appears to be a useful tool in NET patients to predict tumor response and survival outcomes and a negative FDG uptake of the tumor is associated with prolonged PFS and OS.

BACKGROUND/AIMS: Long-term outcomes are understudied in patients with well-differentiated appendiceal neuroendocrine neoplasms (WD-ANENs). We aimed to evaluate the validity of currently applied criteria for completion prophylactic right hemicolectomy (pRHC) and determine its association with patient outcomes, including health-related quality of life (HRQoL).

METHODS: Eligible patients from five European referral centers were divided between those who underwent appendectomy alone and those who underwent completion pRHC. HRQoL EORTC-QLC-C30 questionnaires and cross-sectional imaging data were prospectively collected. Age- and sex-matched healthy controls were recruited for HRQoL analysis' validation.

RESULTS: We included 166 patients (119 women [71.2%]: mean age at baseline: 31 ± 16 years). Mean follow-up was 50.9 ± 54 months. Most patients (152 [92%]) had tumors ≤20 mm in size. Fifty-eight patients (34.9%) underwent pRHC that in final analysis was regarded as an overtreatment in 38/58 (65.5%). In multivariable analysis, tumor size >20 mm was the only independent predictor for lymph node (LN) involvement (p = 0.002). No mortality was reported, whereas 2-, 5- and 10-year recurrence-free survival in patients subjected to postoperative cross-sectional imaging (n = 136) was 98.5%, 97.8%, and 97.8%, respectively. Global HRQoL was not significantly impaired in patients with WD-ANEN compared with age- and sex-matched healthy individuals (median scores 0.83[0.08-1] vs 0.83[0.4-1], respectively; p = 0.929). Among patients with WD-ANEN impaired social functioning (p = 0.016), diarrhea (p = 0.003) and financial difficulties (0.024) were more frequently reported in the pRHC group.

CONCLUSIONS: WD-ANEN is a low-malignant neoplasm with unconfirmed associated mortality, low recurrence rate, and overall preserved HRQoL. pRHC comes at a price of excessive surgery, functional HRQoL issues, and diarrhea. The value per se of a prophylactic surgical approach to patients with WD-ANENs <20 mm is challenged.

Following improvements in the management and outcome of neuroendocrine neoplasms (NENs) in recent years, we see a subset, particularly of pancreatic NENs, which become more aggressive during the course of the disease. This is reflected by an increase in the Ki-67 labelling index, as a marker of proliferation, which may lead to an occasion of increase in grading, but generally does not appear to be correlated with histologically confirmed dedifferentiation. A systematic review of the literature was performed in PubMed, Cochrane Library, and Embase until May 2020 to identify cases that have behaved in such a manner. We screened 244 articles: only seven studies included cases in their cohort, or in a subset of the cohort studied, with a proven increase in the Ki-67 during follow-up through additional biopsy. In addition to these studies, we have also tried to identify possible pathophysiological mechanisms implicated in advanced NENs, although currently no studies appear to have addressed the mechanisms implicated in the switch to a more aggressive biological phenotype over the course of the disease. Such progression of the disease course may demand a change in the management. Summarising the overall evidence, we suggest that future studies should concentrate on changes in the molecular pathways during disease progression with sequential biopsies in order to shed light on the mechanisms that render a neoplasm more aggressive than its initial phenotype or genotype.

Introduction: Lithium-associated hyperparathyroidism (LHPT) was first reported in 1973. It remains unclear if this is a specific endocrinopathy or separate simultaneous medical conditions. Definitive management for lithium-treated patients with calcium dysfunction has yet to be established (1).

Method: We conducted this systematic review of all available studies in English which provide patient material from the adult population (>18 years) illustrating lithium’s association in the development of hypercalcaemia and/or hyperparathyroidism. A predefined review protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO) (CRD 395676). The search used five major databases: Medline, EMBASE, Cochrane Library, PsycINFO, and Web of Science, between 1973 to January 2023, using the keywords hyperparathyroidism, lithium, hypercalcaemia, hypocalcaemia. Review articles and abstracts were excluded.

Result: Of the initial 5418 searches, 169 articles were included for final analysis. Prevalence of hypercalcaemia is reported in approximately 20-30% of lithium-treated patients. Lithium gives moderate increases in calcium levels, with or without elevations in parathyroid hormone. Paradoxically, lithium may be skeletal protective. Multiglandular disease is more common in LHPT than in pHPT, most often consisting of hyperplastic glands. In surgical cases, bilateral exploration is often preferred. Follow-up times are relatively short. No randomised surgical studies exist.

Discussion:

• LHPT appears to be a common endocrinopathy.• Lithium patients with tendency to calcium dysfunction should be carefully monitored.• More radical surgery may lead to health benefits.• Randomized controlled trials should be conducted to identify optimal treatment in patients with LHPT.

Pancreatic neuroendocrine neoplasms (pNENs) are relatively rare tumors that have been increasingly recognized in recent years. They are highly heterogeneous and exhibit a diverse clinical course, along with a variable metastatic propensity related to their molecular biology profile, grade, primary tumor size, and functional status. The pNENs are divided into functioning and nonfunctioning tumor forms. Their pathological classification is based mainly on their histology and proliferative activity. Clinical challenges in their management include - but are not limited to - the inability to establish an early diagnosis in nonfunctioning pNENs and to accurately localize the source of hormonal secretion in functioning ones. Additionally, the role of active surveillance versus surgery for asymptomatic small nonfunctioning tumors is controversial, same as is the impact of palliative surgery in pNENs with distant metastases. Finally, in terms of an individualized treatment approach, there is a relative paucity of evidence on predictable, effective treatment strategies with respect to tumors and patient-related parameters.

Introduction: Autophagy and mitophagy are key homeostatic machineries linked to cancer development and drug resistance.

Aim(s): To assess the levels of autophagy and mitophagy in well differentiated pancreatic neuroendocrine neoplasms (PanNENs) and correlate them with clinico-pathological parameters. 

Materials and methods: Fluorescent immunostaining for the autophagy markers LC3 Βand p62/or LAMP1 was performed on 22 PanNENs and 11 controls of normal pancreatic tissues and validated through Western blotting. Autophagy quantitative scoring was generated for LC3B-positive puncta and analyzed in relation to clinico-pathological parameters. TOMM20/LC3B qualitative assessment of mitophagy levels was undertaken by fluorescent immunostaining. The presence of autophagy/mitophagy was validated by transmission electron microscopy.

Results: Autophagy levels (LC3B-positive puncta/cell) were discriminative for normal vs. NEN pancreatic tissue (p=0.007). A significant association was observed between autophagy levels and tumour grade (Ki67<3% vs. Ki67≥3%; p=0.021), but not functionality (p=0.266) size (cut-off of 20mm; p=0.808), local invasion (p=0.481), lymph node- (p=0.849) and distant metastases (p=0.699). Qualitative assessment of TOMM20/LC3B demonstrated strong mitophagy levels in PanNENs by fluorescent immunostaining as compared to normal tissue. Transmission electron microscopy revealed enhanced autophagy and mitophagy in PanNEN tissue. Response to molecular targeted therapies in metastatic cases (n=4) did not reveal any patterns of association to autophagy levels.

Conclusion: Increased autophagy levels are present in primary tumours of patients with PanNENs and are partially attributed to upregulated mitophagy. Grade was the only clinico-pathological parameter associated with autophagy scores.

Background/aims: We assessed the levels of autophagy and mitophagy, that are linked to cancer development and drug resistance, in well differentiated pancreatic neuroendocrine neoplasms (PanNENs) and correlated them with clinico-pathological parameters.

Methods: Fluorescent immunostaining for the autophagy markers LC3 Beta and p62/or LAMP1 was performed on 22 PanNENs and 11 controls of normal pancreatic tissues and validated through Western blotting. Autophagy quantitative scoring was generated for LC3B-positive puncta and analysed in relation to clinico-pathological parameters. TOMM20/LC3B qualitative assessment of mitophagy levels was undertaken by fluorescent immunostaining. The presence of autophagy/mitophagy was validated by transmission electron microscopy.

Results: Autophagy levels (LC3B-positive puncta/cell) were discriminative for normal vs. NEN pancreatic tissue (p = 0.007). A significant association was observed between autophagy levels and tumour grade (Ki67 < 3% vs. Ki67 >= 3%; p = 0.021), but not functionality (p = 0.266) size (cut-off of 20 mm; p = 0.808), local invasion (p = 0.481), lymph node- (p = 0.849) and distant metastases (p = 0.699). Qualitative assessment of TOMM20/LC3B demonstrated strong mitophagy levels in PanNENs by fluorescent immunostaining as compared with normal tissue. Transmission electron microscopy revealed enhanced autophagy and mitophagy in PanNEN tissue. Response to molecular targeted therapies in metastatic cases (n = 4) did not reveal any patterns of association to autophagy levels.

Conclusions: Increased autophagy levels are present in primary tumours of patients with PanNENs and are partially attributed to upregulated mitophagy. Grade was the only clinico-pathological parameter associated with autophagy scores.

Background: We aimed to identify optimal grading Ki-67 cut-offs to delineate differences in prognosis of patients with small intestinal neuroendocrine tumours (SI-NETs) in terms of overall- and event-free survival rates.

Methods: We included 551 patients with SI-NETs diagnosed from June 15th, 1993, through March 8th, 2021, identified using the SI-NET databases from five European referral centers.

Results: Median age at baseline was 62.3(17-90) years; 252 patients were women (45.7%). All tumours were well-differentiated; 326 were G1 tumours (59.2%), 169 G2(30.7%), only 8 G3(1.5%), while 48 tumourswere of unspecified grade (8.7%). The median Ki67 was 2%(1-70%). 247 patients(44.8%) had distant metastases at baseline (stage IV), 217locoregional disease (41.1%; stage III), whereas 29(7.1%) and 25(4.5%) presented at stages II and I, respectively. Within a mean(SD) follow-up of 51.5(52.9) months, 94 patients(17.1%) died, whereas overall 188 experienced disease recurrence, progression and/or death(34.1%). The median OS was 214.7(95%CI: 152.7-276.6) months and the median EFS was 79.8(95%CI: 68.2-91.5) months, respectively. In multivariable Cox-regression OS analysis, age (HR=1.07, 95%CI: 1.04-1.09; p<0.001), Charlson Comorbidity Index(HR=1.1, 95%CI: 1.03-1.17; p=0.006) and the proposed modified histopathological Ki67 grading system(K67:5-10% group: HR=2.4, 95%CI: 1.3-4.5; p=0.007 and K67≥10% group: HR=5.1, 95%CI: 2.9-9.2; p<0.001) were independent predictors for death. Pertinent EFS analysis, confirmed age(HR=1.04, 95%CI: 1.02-1.05;p<0.001) and the proposed modified histopathological Ki67 grading system(K67≥10% group: HR=4; 95%CI:2.5-6.2;p<0.001) as independent predictors for recurrence, progression and/or death.

Conclusions: Ki-67 proliferation index is an independent predictor of EFS and OS. A modified site-specific histopathological grading system applying Ki-67 cut-offs of 5% and 10% seems more optimal to predict differences in SI-NET patient prognosis

CONTEXT: One of the major prognostic indices in neuroendocrine tumours (NETs) is Ki67 proliferation index.

OBJECTIVE: To identify optimal grading Ki-67 cut-offs to delineate differences in prognosis of patients with small intestinal NETs (SI-NETs).

DESIGN, SETTING, PARTICIPANTS: Multicentre retrospective cohort analysis of 551 SI-NET patients diagnosed from 1993 through 2021 at five European referral centres with a mean(±SD) follow-up time of 51.5(±52.9) months.

MAIN OUTCOME MEASURES: Overall- and event-free survival (OS and EFS) rates.

RESULTS: Median age at baseline was 62.3(range:17-90) years; 252(45.7%) patients were female. All SI-NETs were well-differentiated with 326 being grade 1(G1; 59.2%), 169G2(30.7%), and only 8G3(1.5), while 48 tumours were of unspecified grade (8.7%). The median Ki67 was 2%(range:1-70%). Two-hundred forty-seven patients (44.8%) had distant metastases at baseline (stage IV), 217 locoregional disease (41.1%; stage III), whereas 29(7.1%) and 25(4.5%) presented at stages II and I, respectively. The median OS was 214.7(95%CI:152.7-276.6) months and the median EFS was 79.8(95%CI:68.2-91.5) months, respectively. In multivariable Cox-regression OS analysis, the proposed modified histopathological Ki67 grading system (K67:5-10% group: HR=2.2, 95%CI:1.15-4.31; p=0.018 and K67≥10% group: HR=5.11, 95%CI:2.87-9.09; p<0.001), age (HR=1.07, 95%CI:1.04-1.09; p<0.001), Charlson Comorbidity Index (HR=1.08, 95%CI:1-1.16; p=0.028) and TNM stage (HR=1.79, 95%CI:1.05-3.06; p=0.034) were independent predictors for death. Pertinent EFS analysis, confirmed the proposed modified histopathological Ki67 grading system (K67≥10% group: HR=4.01, 95%CI:2.6-6.37; p<0.001) and age (HR=1.04, 95%CI:1.02-1.05; p<0.001) as independent predictors for recurrence, progression and/or death.

CONCLUSIONS: Ki-67 proliferation index was a strong and independent predictor of OS and EFS. A modified histopathological grading system applying Ki-67 cut-offs of 5 and 10% could be superior to predict differences in SI-NET patient survival outcomes.

INTRODUCTION: The purpose of this study was to evaluate longitudinal changes in Ki-67 indices of SI-NETs and assess the impact of these in overall survival (OS).

METHODS: We screened 551 patients with SI-NETs diagnosed from 1993, through 2021, identified using the SI-NET databases from five European referral centres. Only patients with well-differentiated tumours and available baseline tumour samples and follow-up re-biopsies were included. For tumour grading, apart from 2017 WHO classification system, we applied a recently proposed SI-NET site-specific modified histopathological grading system with Ki-67 cut-offs of 5 and 10%. Uni- and multivariable regression analyses were used to determine whether there was a difference between OS in SI-NET patients stratified by increment of Ki-67 indices over time and/or progression to a higher grade.

RESULTS: We included 45 patients. Median Ki-67 index at SI-NET diagnosis was 2% (range: 0.5-15%). Thirty-three patients had Ki-67 indices &lt;5% (70.2%), 6 had Ki-67: 5-10% (12.8%), and 8 had Ki-67 ≥10% (17%). Mean time to re-biopsy was 48.8 months (SD: ±162.5). At re-biopsy, the median change in Ki-67 index (absolute value; follow-up minus time of diagnosis) was 1% (range: -10 to +38%). An increase in Ki-67 occurred in 20 patients (42.6%); in 14 patients, the change in Ki-67 resulted in progression to higher tumour grade following the modified grading system. Patients with an increment in Ki-67 ≥1% had a median OS of 32.9 months versus 80.5 months in patients without (HR = 5.6, 95% CI: 1.42-22.02; p = 0.014). When applying the novel modified histopathological grading system for SI-NETs, patients with grade progression had a median OS of 32.9 months versus 53.7 months in those without (HR = 4.61, 95% CI: 1.22-13.54; p = 0.022). At multivariable analysis, grade progression was confirmed as an independent predictor for death (HR = 7.2, 95% CI: 1.58-32.82; p = 0.011).

CONCLUSIONS: Metachronous increment in Ki-67 indices and related grade progression over time following a site-specific modified histopathological grading system with Ki-67 cut-offs of 5 and 10% is observed in approximately 1/3 of SI-NETs subjected to re-biopsy and it is associated with worse survival outcomes.

We aimed to assess the prognostic impact of tumor- and patient-related parameters in patients with stage I-III small intestinal neuroendocrine tumors (SI-NETs), who underwent locoregional resective surgery (LRS) with curative intent. We included 229 patients with stage I-III SI-NETs diagnosed from June 15, 1993, through March 8, 2021, identified using the SI-NET databases from five European referral centers. Mean ± SD age at baseline was 62.5 ± 13.6 years; 111/229 patients were women (49.3%). All tumors were well-differentiated; 160 were grade 1 (G1) tumors, 51 were G2, two were G3 and 18 tumors were of unspecified grade (median Ki-67: 2%, range 1%-50%). One-hundred and sixty-three patients (71.2%) had lymph node (LN) involvement. The median number of retrieved lymph nodes was 10 (0-63), whereas the median number of positive LNs was 2 (0-43). After a mean ± SD follow-up of 54.1 ± 64.1 months, 60 patients experienced disease recurrence at a median (range) of 36.2 (2.5-285.1) months. The 5- and 10-year recurrence-free survival (RFS) rates were 66.6% and 49.3% respectively. In univariable analysis, there was no difference in RFS and overall survival (OS) between LN-positive and LN-negative patients (log-rank, p = .380 and .198, respectively). However, in stage IIIb patients who underwent mesenteric lymph node dissection (MLND) with a minimum of five retrieved LN (n = 125), five or more LN metastases were associated with shorter RFS (median RFS [95% CI] = 107.4 [0-229.6] vs. 73.7 [35.3-112.1] months; log-rank, p = .048). In addition, patients with G2 tumors exhibited shorter RFS compared to patients with G1 tumors (median RFS [95% confidence interval (CI)] = 46.9 [36.4-57.3] vs. 120.7 [82.7-158.8] months; log-rank, p = .001). In multivariable Cox-regression RFS analysis in stage IIIb patients, the Ki-67 proliferation index (hazard ratio = 1.08, 95% CI = 1.035-1.131; p < .0001) and the number of LN metastases (hazard ratio = 1.06, 95% CI = 1.001-1.125; p = .047) were independent prognostic factors for RFS. In conclusion, LRS with a meticulous MLND and a minimum number of five harvested LNs appears to be critical in the surgical management of SI-NET patients with locoregional disease. In patients who underwent LRS and MLND, the Ki-67 proliferation index and the LN metastases count were independent predictors of RFS.

Background: Long-term outcomes, including health-related quality of life (HRQoL) issues are understudied in patients with well-differentiated ppendiceal neuroendocrine neoplasms (WD-ANENs). We aimed to evaluate the validity of currently applied criteria for completion prophylactic right hemicolectomy (pRHC) and determine its association with patient outcomes.

Methods: This cohort study included patients with WD-ANENs from five European Centers of Excellence for neuroendocrine tumors. Eligible patients were divided between those who underwent appendectomy alone and those who underwent pRHC. HRQoL EORTCqlqc30 questionnaires and cross-sectional imaging data were prospectively collected.

Results: The 166 patients included 119 women (71.2%). Mean age was 31 ± 16 years. Mean follow-up was 51 ± 54 months. Most patients (152[92%]) had tumors≤20 mm. Fifty-eight patients (34.9%) underwent pRHC that was unnecessary in 65.5%(38/58); and in 79.1%(34/43) of tumors≤20 mm. In multivariable analysis, tumor size>20 mm was the only independent predictor for lymph node (LN) positivity(p = 0.021). No disease-specific mortality was reported. Three patients developed recurrence (n = 2inthepRHC group vs. n = 1 in the appendectomy group;p = 0.263). Although global HRQol was not significantly depreciated in patients undergoing pRHC compared to appendectomy alone (median scores 0.79[0.25-1] vs. 0.83[0.08-1], respectively; p = 0.738), impaired social functioning (p = 0.016), diarrhea (p = 0.003) and financial difficulties (0.024) were more frequently reported in the pRHC group. Furthermore, physical-(p = 0.066) and role functioning (p = 0.055), as well as constipation issues(p = 0.072) emerged in the pRHC group with marginal significance.

Conclusion: pRHC in WD-ANENs comes at a high rate of unnecessary procedures, functional HRQoL issues and diarrhoea. LN positivity at pRHC may lack prognostic significance, as no disease-specific mortality and scarce recurrence was evident in this series. The validity of contemporary criteria and the value per se of pRHC to patients with WD-ANEN is challenged.

Introduction: There is a continuity of changes from ECL-cell hyperplasia to type 1 gastric neuroendocrine neoplasms (GNEN1) development with important clinical implications.  

Aim(s): Although the effect of the circadian clock system on neuroendocrine tumorigenesis has been addressed, the role of the peripheral clock system in the transition from ECL-cell hyperplasia to GNEN1 remains to be explored.

Materials and methods: Six GNEN1 patients and 10 patients with ECL-cell hyperplasia were included. Blood samples were collected at 8 am, 3pm and 10pm for peripheral blood mononuclear  ells (PBMCs) isolation. The mRNA expression of clock-related genes (CLOCK, BMAL1, CRY-1, PER2, ROR-α and REV-ERBβ) were evaluated by real-time quantitative PCR from PBMCs.  

Results: In GNEN1 patients, BMAL genes where lower expressed at night than early in the morning (p=0.02), whereas patients with ECL-cell hyperplasia expressed lower levels of PER2 and REV-ERBβ (p=0.03 and p=0.05,respectively). In addition, GNEN1 patients expressed lower levels of CLOCK, PER2 and REV-ERBβ in the early evening than in the morning (p=0.04; p=0.03; p=0.05, respectively). When comparing the two groups (GNEN1 vs. ECL-cell hyperplasia) at the three different time points, a marginal increase in CLOCK, PER2 and REV-ERBβ expression early in the morning (p=0.06, 0.02 and 0.07, respectively) along with a marginal increase in REV-ERBβ and BMAL expression in the early evening (p=0.09 and p=0.08, respectively) and a marginal increase in BMAL at night (p=0.09) in GNEN1 patients was observed.

Conclusion: Our findings point towards an upregulated expression of clock-related genes in patients with GNEN1 as compared to ECL-cell hyperplasia, suggesting  a possible involvement in GNEN1 tumorigenesis that needs to be confirmed in a larger patients group.

INTRODUCTION: Although minimally invasive surgery is becoming the standard technique in gastrointestinal surgery, implementation for small bowel neuroendocrine neoplasms (SB-NEN) is lagging behind. The aim of this international survey was to gain insights into attitudes towards minimally invasive surgery for resection of SB-NEN and current practices.

METHODS: An anonymous survey was sent to surgeons between February and May 2021 via (neuro)endocrine and colorectal societies worldwide. The survey consisted of questions regarding experience of the surgeon with minimally invasive SB-NEN resection and training.

RESULTS: A total of 58 responses from five societies across 20 countries were included. Forty-one (71%) respondents worked at academic centers. Thirty-seven (64%) practiced colorectal surgery, 24 (41%) endocrine surgery and 45 (78%) had experience in advanced minimally invasive surgery. An open, laparoscopic or robotic approach was preferred by 23 (42%), 24 (44%), and 8 (15%) respondents, respectively. Reasons to opt for a minimally invasive approach were mainly related to peri-operative benefits, while an open approach was preferred for optimal mesenteric lymphadenectomy and tactile feedback. Additional training in minimally invasive SB-NEN resection was welcomed by 29 (52%) respondents. Forty-three (74%) respondents were interested in collaborating in future studies, with a cumulative median (IQR) annual case load of 172 (86-258).

CONCLUSIONS: Among respondents, 69% applies minimally invasive surgery for resection of SB-NEN. Arguments for specific operative approaches differ, and insufficient training in advanced laparoscopic techniques seems to be a barrier. Future collaborative studies can provide better insight in selection criteria and optimal technique.

Mesenteric fibrosis (MF) constitutes an underrecognized sequela in patients with small intestinal neuroendocrine neoplasms (SI-NENs), often complicating the disease clinical course. The aim of the present systematic review, carried out by Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology, is to provide an update in evolving aspects of MF pathogenesis and its clinical management in SI-NENs. Complex and dynamic interactions are present in the microenvironment of tumor deposits in the mesentery. Serotonin, as well as the signaling pathways of certain growth factors play a pivotal, yet not fully elucidated role in the pathogenesis of MF. Clinically, MF often results in significant morbidity by causing either acute complications, such as intestinal obstruction and/or acute ischemia or more chronic conditions involving abdominal pain, venous stasis, malabsorption and malnutrition. Surgical resection in patients with locoregional disease only or symptomatic distant stage disease, as well as palliative minimally invasive interventions in advanced inoperable cases seem clinically meaningful, whereas currently available systemic and/or targeted treatments do not unequivocally affect the development of MF in SI-NENs. Increased awareness and improved understanding of the molecular pathogenesis of MF in SI-NENs may provide better diagnostic and predictive tools for its timely recognition and intervention and also facilitates the development of agents targeting MF.

This review reports on the currently available medical treatment options for the control of symptoms due to carcinoid syndrome in patients with neuroendocrine tumors. The efficacy and adverse events (AEs) of approved drugs such as somatostatin analogues (SSA), telotristat ethyl (TE) and interferon-alpha, are reviewed. Somatostatin analogues remain the standard treatment of carcinoid syndrome based on the high expression of somatostatin receptors and the resulting inhibition of secretion of bioactive compounds; their use is associated with relatively mild AEs, involving mainly the gastrointestinal system, and being usually transient. Although dose escalation of SSA remains an unapproved option, it is clinically implemented to alleviate symptoms in refractory carcinoid syndrome and supported by the most recent guidelines. The side effects associated with the increased dose are in general mild and consistent with standard dose of SSA. Telotristat ethyl, an oral inhibitor of tryptophan hydroxylase, the rate-limiting enzyme in serotonin biosynthesis, represents a rather novel innovative treatment option in patients with carcinoid syndrome suffering from diarrhea and complements the standard therapy of SSA. Given the low toxicity profile, TE may be considered an early add-on treatment to SSA in patients with uncontrolled carcinoid syndrome. However, further prolonged follow-up of patients treated with TE may be needed to exclude potential AEs, such as liver toxicity or depressed mood, in patients with long-term treatment. Interferon alpha is a cytokine with direct inhibitory effect on hormone secretion and tumor cell proliferation and an approved therapy in carcinoid syndrome but is associated with significant AEs in the majority of the patients requiring frequently dose reduction. The finding of a more favorable tolerability of pegylated interferon needs to be confirmed in a prospective study.

Summary: Dropout from placebo arms in randomized-controlled trials is a surrogate for nocebo responses, resulting from patients' negative expectations to treatment. Among 16,460 placebo-treated patients in oral anti-osteoporotic drug trials, nocebo dropouts were 8% on average, being higher in older patients. This implies that nocebo may contribute to the osteoporosis treatment gap in clinical practice.

Purpose: Osteoporosis is a common disease requiring long-term treatment. Despite the availability of effective anti-osteoporotic drugs, adherence to treatment is low. Nocebo, a behavior mostly related to the negative expectations to a certain treatment, decreases adherence and negatively affects treatment outcomes and health-related care costs in chronic diseases. Since in double-blind placebo-controlled randomized trials any unfavorable outcome leading to discontinuation in placebo arms is considered as nocebo, we aimed to investigate the size of nocebo response in patients participating in osteoporosis trials.

Methods: We searched MEDLINE, EMBASE, SCOPUS, and Cochrane databases for dropouts due to reported adverse events in the placebo arms (nocebo dropouts) in all double-blind trials investigating anti-osteoporotic drugs published between January 1993 and March 2022. Only data on bisphosphonates and selective estrogen receptor modulators (SERMs) were analyzed (Prospero registration number CRD42020212843).

Results: Data from 44 trials were extracted. In 16,460 placebo-treated patients, the pooled nocebo-dropout was 8% both for bisphosphonates (average: 0.08; range 0.01-0.27; 95%CI 0.06-0.10) and SERMs (average: 0.08; range 0.03-0.15; 95%CI 0.05-0.13). Nocebo-dropouts were higher in bisphosphonate trials enrolling individuals >= 65 years (11%) (n = 18) compared to trials enrolling younger individuals (6%) (n = 18) (average: 0.11; 95%CI 0.08-0.13 vs. average: 0.06; 95%CI 0.05-0.08, respectively, p = 0.001). Participants' sex, dosing-intervals, publication year, or severity of osteoporosis had no impact on the nocebo-dropouts.

Conclusion: Almost 1 in 10 osteoporosis patients receiving placebo in trials of bisphosphonates and SERMs experiences AEs leading to dropout, implying that nocebo contributes to treatment-discontinuation in clinical practice. Efforts to identify and minimize nocebo, especially in older patients, are warranted.

Introduction: Fine-needle aspiration cytology (FNAC) is an effective tool in the diagnostic work-up of patients with thyroid nodules. The aim of our study was to assess the diagnostic sensitivity of FNAC in thyroid cancer (TC) in Sweden by correlating the findings of preoperative FNAC with those obtained through final histology of the surgical specimen.

Methods: A Swedish nationwide cohort of patients having surgery for TC (n = 2519) from the Scandinavian Quality Register for Thyroid, Parathyroid and Adrenal surgery between 2004 and 2013 was obtained. Data was validated through scrutinizing patient FNAC and histology reports.

Results: Among the 2519 cases operated with a final diagnosis of TC, the diagnosis was substantiated and validated through the histology report in 2332 cases (92.6%), included in the present study. Among these, 1679 patients (72%) were female and the median age at TC diagnosis was 52.3 years (range 18-94.6). In 353 cases (15.1%) FNAC was not performed at all; whereas in the remaining 1965 cases, the diagnostic sensitivity of FNAC was 81.6%. In lesions > 1 cm, FNAC diagnostic sensitivity reached 86.5%, whereas in lesions < 1 cm, FNAC yielded a sensitivity of 61.5%. Approximately 85% of FNACs (n = 1981/2332) were performed using ultra-sonographic (US) guidance. In TC lesions > 1 cm, the diagnostic sensitivity of US-guided FNAC (n = 1504) was 86.9% as compared to 76.9% in clinically applied FNAC without US utilization (n = 118).

Conclusions: FNAC is performed in most patients operated for TC in Sweden (85%) and retains its value as a tool in TC diagnostic work-up with an overall sensitivity of 82%, reaching 87% in lesions > 1 cm, that harbor clinically relevant TC.

PURPOSE: To assess the impact of fine-needle aspiration cytology (FNAC) in the extent of surgery in patients with thyroid cancer (TC) and the associated surgical morbidity in primary and completion setting.

METHODS: A Swedish nationwide cohort of patients having surgery for TC (n = 2519) from the Scandinavian Quality Register for Thyroid, Parathyroid and Adrenal surgery between 2004 and 2013 was obtained. Data was validated through scrutinizing FNAC and histology reports.

RESULTS: Among the 2519 cases operated for TC, the diagnosis was substantiated and validated through the histology report in 2332 cases (92.6%). Among these, 1679 patients (72%) were female, and the median age at TC diagnosis was 52.3 years (range 18-94.6). Less than total thyroidectomy (LTT) was undertaken in 944 whereas total thyroidectomy (TT) in 1388 cases. The intermediate FNAC categories of atypia of undetermined significance/follicular lesion of undetermined significance (AUS/ FLUS), as well as suspicion for follicular neoplasm (SFN) lesions were more often encountered in LTT (n = 314, 33.3%) than TT (n = 63, 4.6%), whereas FNACs suspicion for malignancy and/or malignancy were overrepresented in TT (n = 963, 69.4%). Completion thyroidectomies were undertaken in 553 patients out of 944 that initially had LTT. In 201 cases with cancer lesions > 1 cm, other than FTC (Follicular TC)/ HTC (Hürthle cell TC) subjected to primary LTT, inadequate procedures were undertaken in 81 due to absent, Bethesda I or II FNAC categories, preoperatively. Complications at completion of surgery in this particular setting were 0.5% for RLN palsy (n = 1) and 1% (n = 2) for hypoparathyroidism 6 months postoperatively. The overall postoperative complication rate was higher in primary TT vs. LTT for RLN palsy (4.8% [n = 67] vs. 2.4% [n = 23]; p = 0.003) and permanent hypoparathyroidism (6.8% [n = 95] vs. 0.8% [n = 8]; p < 0.0001).

CONCLUSIONS: FNAC results appear to affect surgical planning in TC as intermediate FNAC categories lead more often to LTT. Overall, inadequate procedures necessitating completion surgery are encountered in up to 15% of TC patients subjected to LTT due to absent, inconclusive, or misleading FNAC, preoperatively. However, completion of thyroidectomy in this setting did not yield significant surgical morbidity. Primary LTT is a safer primary approach compared to TT in respect of RLN palsy and permanent hypoparathyroidism complication rates; therefore, primary TT should probably be reserved for lesions > 1 cm or even larger with suspicion for malignancy or malignant FNAC.

Introduction: Prevalence of distant stage disease and overall mortality rates vary considerably among patients with multiple endocrine neoplasia type 1 (MEN1).

Aim(s): To study the metastatic potential of MEN1 different components, and the associated mortality rates.

Materials and methods: We included patients with clinical and/or genetic diagnosis of MEN1, followed at the Endocrinology Unit, First Department of Propaedeutic and Internal Medicine, Laiko General Hospital of Athens, Greece.

Results: We included 123 patients; 56 were women (45.9%). MEN1 first manifestation, commonly hyperparathyroidism, appeared at <25 years of age in 46 patients (38%), between 25-40 years in 49 (39,8%) and >40 years in 23 patients (19,4%). Among patients with pNETs (n=79), 23 had grade 2 and one grade 3 tumors, respectively. Fifteen patients (19%) had secretory pNETs for either insulin or gastrin. PNET distant metastases, mainly to the liver, were present in seven patients (8.9%). Overall, atypical lung (AC) and thymic carcinoids (TC) were encountered in three and seven patients, respectively (two of these had ACTH dependent Cushing’s syndrome); AC and/or TC distant metastases were encountered in all ten patients, harbouring these primaries. Overall, 12 patients with stage IV disease manifested disease progression according to RECIST criteria, with a mean duration of disease for pNETs 14 years and for AC and TC 8 years and died. The mortality was associated with the disease progression in 11 patients, and one died because of sepsis.

Conclusion: Spread metastatic disease is encountered in all MEN1-associated AC and TC tumors and in a subset of pNETs, approximately 9%. These MEN1 components account for the disease associated mortality at a 10% rate in our Greek MEN1 cohort.

Introduction: Above-label doses of long-acting somatostatin analogues (SSAs) are increasingly used for the control of secretory syndrome or as anti-proliferative treatment in patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs).

Aim(s): The aim of this study was to evaluate the anti-proliferative effect of increased dose of SSAs in patients with GEP-NETs.

Materials and methods: We collected retrospectively the data of patients with GEP-NETs that received SSAs every 3 or 2 weeks, after disease progression on standard 4-weekly doses. We analysed clinical, biochemical and radiographic response data and identified factors that may influence the outcome.

Results: We analysed the data of 16 patients. 7 patients suffered from pancreatic NET (pNET) and 9 from small intestinal NET (si-NET). Indications for dose increase were radiographic progression (62,5%), increasing biomarkers (12,5%) or inadequate syndrome control (25%). Among patients with radiographic progression before the escalation of SSA dose, 3 had disease stabilization and 7 eventually progressed radiographically. Median PFSwas 36 months. PNETs were associated with a significantly lower PFS compared to si-NETs (P= 0.041). Patients with NET with a Ki-67 labelling index≤5 displayed a significantly higher PFS (P= 0.047). No significant difference was observed between patients who received above-label SSAs due to clinical/biochemical or radiographic response (P=0.1). In univariate analysis, the Ki-67≤5 was marginally associated with significantly longer PFS (P=0.05).

Conclusion: The administration of above-label doses of SSAs maybe a valuable option in patients who progress on the standard 4-weekly regimen, especially in patients with si-NETs or a Ki-67 labelling index≤5.

Pheochromocytomas/Paragangliomas (PPGLs) and adrenocortical tumors are rare neoplasms with significant heterogeneity in their biologic and clinical behavior. Current diagnostic and predictive biomarkers include hormone secretion, as well as histopathological and genetic features. PPGL diagnosis is based on biochemical measurement of catecholamines/metanephrines, while histopathological scoring systems have been proposed to predict the risk of malignancy. Adrenocortical tumors are mostly benign, but some can be malignant. Currently, the stage of disease at diagnosis and tumor grade, appear to be the most powerful prognostic factors. However, recent genomic and proteomic studies have identified new genetic and circulating biomarkers, including genes, immunohistochemical markers and micro-RNAs that display high specificity and sensitivity as diagnostic or prognostic tools. In addition, new molecular classifications have been proposed that divide adrenal tumors in distinct subgroups with different clinical outcomes.

Pancreatic metastases (PMs) from neuroendocrine neoplasms (NENs) are rare but the increased sensitivity of new diagnostic tools such as 68 Ga-DOTATATE PET/CT has resulted in their increased recognition at initial diagnosis or follow-up. A retrospective analysis of the data of patients from six tertiary referral centres was performed in order to identify the characteristics and the prognostic significance of PMs in patients with NENs. We used a control group of 69 age-, sex- and primary tumour - matched NEN patients from the same cohort with stage IV disease but no PMs. Overall survival (OS) was assessed using the Kaplan-Meier method log-rank analysis was used to assess the impact of various clinical and histopathological variables in OS. We identified 25 patients (11 females) with PMs with a median age at diagnosis of 60 years. The small intestine was the most common primary (80%) with a prevalence of 4.2% PMs (21/506). Fourteen patients presented with synchronous PMs whereas 11 developed metachronous PMs after a median time of 28 months (range: 7-168 months). Grading was available in 24 patients; 16 patients had G1 tumours, four G2, two atypical lung carcinoid, one typical and one atypical thymic carcinoid. Most patients had other concomitant metastases (12 hepatic, 4 lung and 6 bone) while five patients exhibited peritoneal carcinomatosis. Median OS in the PMs group was not reached compared with 212 months in the control group (95% CI: 26-398). The univariate analysis identified no prognostic factors statistically significantly associated with the OS. In conclusion, PMs are encountered with a low prevalence among NEN patients mostly developing in patients with advanced metastatic disease. The presence of PMs does not seem to be associated with a negative prognostic impact in OS.

The role of primary tumor resection in patients with pancreatic neuroendocrine neoplasms (PanNENs) and unresectable distant metastases remains controversial. We aimed to evaluate the effect of palliative primary tumor resection (PPTR) on overall survival (OS) in this setting. We searched the MEDLINE, Embase, Cochrane Library, Web of Science and SCOPUS databases up to January 2020 and used the Newcastle-Ottawa scale (NOS) criteria to assess quality/risk of bias. A total of 5661 articles were screened. In 10 studies, 5551 unique patients with stage IV PanNEN and unresectable metastases were included. The five-year OS for PanNEN patients undergoing PPTR in stage IV was 56.6% vs. 23.9% in the non-surgically treated patients (random effects relative risk (RR): 1.70; 95% CI: 1.53-1.89). Adjusted analysis of pooled hazard ratios (HR) confirmed longer OS in PanNEN patients undergoing PPTR (random effects HR: 2.67; 95% CI: 2.24-3.18). Cumulative OS analysis confirmed an attenuated survival benefit over time. The complication rate of PPTR was as high as 27%. In conclusion, PPTR may exert a survival benefit in stage IV PanNEN. However, the included studies were subject to selection bias, and special consideration should be given to PPTR anchored to a multimodal treatment strategy. Further longitudinal studies are warranted, with long-term follow-up addressing the survival outcomes associated with surgery in stage IV disease.

Introduction: Small Intestinal Neuroendocrine Neoplasms (SI-NENs) may rarely metastasize to the left supraclavicular lymph nodes, also known as Virchow’s node metastasis (VM).

Aim(s): Data on prevalence, prognostic significance and clinical course of disease for SI-NEN patients with VM is limited.

Materials and methods: In this retrospective analysis of 231 SI-NEN patients treated at two tertiary referal centers we found nine patients with VM. We used a control group of 18 age-and sex-matched SI-NEN patients from the same cohort with stage IV disease, but no extrahepatic metastases.

Results: VM prevalence was 3.9% (9/231; 5 females, median age at VM diagnosis 65 years). Two patients had G1, 5 G2 tumours and 2 of unspecified grade. Four patients presented with synchronous VM, whereas 3 developed metachronous VM after a median of 24 months (range: 4.8–117.6 months). Hepatic metastases were present in 7 patients, extrahepatic metastases (EM) in 8 (6 para-aortic distant lymph node metastases, 1 lung and 1 pancreatic metastasis) and peritoneal carcinomatosis in 2 patients. There was no difference in best-recorded responses to 1st line treatment according to RECIST 1.1 as well as progression-free (PFS) and overall survival rates (PFS) between patients with VM and those in the control group (Chi-square p=0.516; PFS: 71.7 vs. 106.9 months [95%CI 38.1-175.8]; log-rank p=0.855; OS: 138.6 [95%CI 17.2–260] vs. 109.9 [95%CI 91.7–128] months; log-rank p=0.533).

Conclusion: VM is relatively rare in patients with SI-NENs. It is more often encountered in patients withG2 tumors and EM, mainly to distant para-aortic lymph nodes. Its presence does not seem to impact patients’ survival outcomes and treatment responses, when compared to age-and sex-matched patients with stage IV disease. 

Introduction: The prevalence of bone metastases (BM) in small intestinal neuroendocrine tumors (Si-NET) ranges from 5 to 23 %.

Aim(s): The aim of our study was to evaluate the overall survival (OS) and the associated symptoms, in particular bone-related pain and fractures in Si-NET patients with BM, which previously have been sparsely described. 

Materials and methods: This is a retrospective cohort study between 1st of January 2010 and 20th of March 2023. We included 133 Si-NET patients with BM detected at 68Gallium-DOTATOC-octreotate PET/CT (68Ga-SSA-PET/CT). Patients were treated and followed at a tertiary referral hospital in Sweden, Uppsala University Hospital. Patients’ characteristics were collected including data on BM-related symptoms, fractures and treatment with analgetics due to bone-related pain. Patients were divided into two groups, those with 1-5 BM or > 5 BM.

Results: We included 133 patients, 64 were women (48%), 74 (56 %) had < 5 BM while 59 (44%) had > 5 BM. Synchronous BM were encountered in 54 patients (41%) at NET diagnosis. Eighteen patients were treated for BM related pain and two had a fracture related to SI-NET BM. Five-year OS was 42 % (median OS 38 months, range 1-209 months). The OS of patients with >5 BM was shorter compared to that of patients with ≤5 BM (5-year OS 21 % vs 58%; p-=0.028) at univariable log-rank analysis. Concurrent carcinoid heart disease was present in 29 Si-NET patients with BM (22%) and was more frequently found in those with > 10 BM (40%).

Conclusion: The number of BM seems to affect OS, as presence of > 5 BM is associated with shorter OS. More extensive bone tumor burden with >10 BM, isl inked with the presence of carcinoid heart disease. Fractures are rare and bone-related pain treatment is needed in up to 14 % of patients. 

Introduction: Neuroendocrine metastases to the orbita, heart, breast, bone, Virchow's lymph node, and pancreas are rarely encountered in small intestinal (SI-NETs) and pancreatic NETs (P-NETs).

Aim(s): We aimed to assessthe prevalence of rare metastatic locations in patients with well-differentiated SI-NETs and P-NETs, who had undergone 68Ga-DOTATOC-PET/CT at diagnosis and/or follow-up.

Materials and methods: In this retrospective analysis of 753 SI-NET patients and 418 P-NET patients treated at two tertiary referral centers, rare metastases were evident in 26.5% (310/1171) of the patient cohort.

Results: Among patients with rare metastases (n=310), 45 % were women and median age at metastases diagnosis was 70 years (43-90). Median Ki-67 was 7% (1-70); 106 were G1 tumors, 142 G2, 11 G3 and 51 of unknown grade. Rare metastatic sites were present in bone 18 % (215/1171), Virchow's lymph node 6 % (75/1171) and 4 % (42/1171) in the lung/pleura. Metastases to the pancreas, breast, heart and orbita were only encountered in SI-NET primaries with a frequency of 5 % (41/753), 2 % (17/753), 2 % (14/753) and 2 % (12/753) respectively. Concomitant liver metastases were present in 86 %. Uncommon metastases were more frequent in SI-NET as compared with P-NET primaries, 255/753 [34%] vs. 55/418 [13%], p ˂0.00001. Bone metastases were present in 23 % (175/753) of SI-NET and 10 % (40/418) of p-NET primaries.

Conclusion: In conclusion, rare metastases are more frequent in SI-NET than p-NETs. The variety and pattern of rare metastases seems different between SI-NETs and P-NET primaries, as orbita, heart, breast and Virchow's lymph node deposits were only encountered in SI-NETs patients; and bone metastases were approximately twice more often inthis group. 

Metastases outside the liver and abdominal/retroperitoneal lymph nodes are nowadays detected frequently in patients with neuroendocrine tumours (NETs), owing to the high sensitivity of positron emission tomography (PET) with Gallium-68-DOTA-somatostatin analogues (68Ga-SSA) and concomitant diagnostic computed tomography (CT). Our aim was to determine the prevalence of extra-abdominal metastases on 68Ga-DOTATOC-PET/CT in a cohort of patients with small intestinal (Si-NET) and pancreatic NET (Pan-NET), as well as that of pancreatic metastasis in patients with Si-NET. Among 2090 patients examined by 68Ga-DOTATOC-PET/CT at two tertiary referral centres, a total of 1177 patients with a history of Si- or Pan-NET, were identified. The most recent 68Ga-DOTATOC-PET/CT report for each patient was reviewed, and the location and number of metastases of interest were recorded. Lesions outside the liver and abdominal nodes were found in 26% of patients (n = 310/1177), of whom 21.5% (255/1177) were diagnosed with Si-NET and 4.5% (55/1177) Pan-NET. Bone metastases were found in 18.4% (215/1177), metastases to Virchow's lymph node in 7.1% (83/1177), and lung/pleura in 4.8% (56/1177). In the subset of 255 Si-NET patients, 5.4% (41/255) manifested lesions in the pancreas, 1.5% in the breast (18/255), 1.3% in the heart (15/255) and 1% in the orbita (12/255). In Si-NET patients, the Ki-67 proliferation index was higher in those with ≥2 metastatic sites of interest, than with 1 metastatic site, (p <0.001). Overall, extra-abdominal or pancreatic metastases were more often found in patients with Si-NET (34%) than in those with Pan-NET (13%) (p <0.001). Bone metastases were 2.6 times more frequent in patients with Si-NET compared to Pan-NET patients (p <0.001). Lesions to the breast and orbita were encountered in almost only Si-NET patients. In conclusion, lesions outside the liver and abdominal nodes were detected in as many as 26% of the patients, with different prevalence and metastatic patterns in patients with Si-NET compared to Pan-NET. The impact of such metastases on overall survival and clinical decision-making needs further evaluation.

Introduction: There are only few studies on the diagnostic value of serum 5HIAA as compared to the 24-hours urinary sampling method and a lack of evidence on the prognostic significance of its serum levels, as well as the markers' ability to predict changes in disease status.

Aim(s): Our aim was to investigate the clinical utility of serum 5HIAA for diagnostic purposes and disease surveillance in a cohort of patients with well-differentiated neuroendocrine neoplasms (WD-NENs).

Materials and methods: Forty-eight patients with WD-NENs and concurrent serum and urinary 5HIAA testing as well as CT/MRI imaging were included.

Results: A positive correlation between disease stage and serum 5HIAA positivity (Pearson Chi-square p=0.017), and between liver tumor burden and serum 5HIAA levels (Spearman’s rank correlation coefficient: 0.46; p=0.013) was confirmed. Further analysis did not reveal any correlation between RECIST 1.1 responses and >25% changes in serum 5HIAA levels (Fisher ́s exact test p=0.735). The concordance rate of serum and urinary 5HIAA positivity at standardized laboratory cut-offs was 75%. In patients without any impairment of the renal function, the concordance between the two tests was as high as 89% and a sensitivity and specificity of 80% and 88.9%, respectively was evident (Cohen’s kappa coefficient=0.685).

Conclusion: Serum 5HIAA performs well compared to urinary testing for diagnostic purposes and corresponds well to tumor stage and liver tumor burden. However, it is not adequate to predict tumor progression. 

Our aim was to investigate the clinical utility of serum 5HIAA for disease surveillance and diagnostic purposes in a cohort of patients with well-differentiated neuroendocrine neoplasms (WD-NENs). Forty-eight patients with WD-NENs and concurrent serum and urinary 5HIAA testing, as well as CT/MRI imaging, were included. Analysis of matching-pairs did not reveal any association between RECIST 1.1 responses and changes in serum 5HIAA levels (p = 0.673). In addition, no correlation was evident between RECIST 1.1 responses and >10%, >25% or >50% changes in serum 5HIAA levels (Fisher's exact test p = 0.380, p > 0.999, and p > 0.999, respectively). The presence of liver metastases and extensive liver tumor involvement were associated with higher serum 5HIAA levels (p = 0.045 and p = 0.041, respectively). We also confirmed a strong linear correlation between the measurements of serum and urine 5HIAA (n = 24, r = 0.791, p < 0.0001). The concordance rate of serum and urinary 5HIAA positivity at standardized laboratory cut-offs was 75%. In patients with normal renal function tests, the concordance between the two methods was as high as 89%, and a sensitivity and specificity of 80% and 88.9%, respectively, was evident (Cohen's kappa coefficient = 0.685). In conclusion, serum 5HIAA performs well compared to urinary testing for diagnostic purposes, mainly in advanced disease stages, and corresponds well to liver tumor burden. However, it is not adequate to predict tumor progression. 

Small intestinal neuroendocrine tumors (SI-NETs) may rarely metastasize to the left supraclavicular lymph nodes, also known as Virchow's node metastasis (VM). Data on prevalence, prognostic significance, and clinical course of disease for SI-NET patients with VM is limited. In this retrospective analysis of 230 SI-NET patients treated at two tertiary referral centers, we found nine patients with VM (prevalence 3.9%). Among those, there were 5 females and median age at SI-NET and VM diagnosis was 61 and 65 years, respectively. Two patients had G1 tumors and five G2, while two tumors were of unspecified grade (median Ki67: 7%, range 2-15%). Four patients presented with synchronous VM, whereas five developed metachronous VM after a median of twenty-four months (range: 4.8-117.6 months). Hepatic metastases were present in seven patients, extrahepatic metastases (EM) in eight (six para-aortic distant lymph node metastases, one lung and one pancreatic metastasis), whereas peritoneal carcinomatosis (PC) in two patients. We used a control group of 18 age- and sex-matched SI-NET patients from the same cohort with stage IV disease but no extra-abdominal metastases. There was no difference in best-recorded response to first line treatment according to RECIST 1.1 as well as progression-free survival (PFS) between patients with VM and those in the control group (Chi-square test p = 0.516; PFS 71.7 vs. 106.9 months [95% CI 38.1-175.8]; log-rank p = 0.855). In addition, median overall survival (OS) of SI-NET patients with VM did not differ from those in the control group (138.6 [95% CI 17.2-260] vs. 109.9 [95% CI 91.7-128] months; log-rank p = 0.533). In conclusion, VM, although relatively rare in patients with SI-NETs, is more often encountered in patients with G2 tumors and established distant para-aortic lymph node metastases. The presence of VM in SI-NET patients does not seem to impact patients' survival outcomes and treatment responses, when compared to age- and sex-matched SI-NET patients with stage IV disease confined in the abdomen.

Introduction: The prevalence of Bone metastases (BM) in small intestinal neuroendocrine tumours (Si-NET) ranges from 6-23 % and has increased due to new radiology modalities. The aim of our study was to evaluate the overall survival (OS) and the associated symptoms, in particular bone-related pain and fractures in Si-NETpatients with BM.

Method: Retrospective cohort study between 2010-2023 including 138 Si-NET patients with BM detected at 68 Gallium-DOTATOC-PET/CT, treated and followed at Uppsala University Hospital in Sweden. Patients were grouped into two groups according to their number of BM; ≤ BM or > 5 BM. We also included 77 sex and age matched control patients with Si-NET and liver metastases, matched to 77 Si-NET patients with BM and liver metastases.

Result: Of 138 patients, 14 % were treated for BM related pain and 4% patients had a fracture related to Si-NET BM. OS of patients with >5 BM was shorter compared to patients with ≤5 BM (5-year OS 21 % vs 58%; p-=0.028). Concurrent carcinoid heart disease was present in 22% of Si-NET patients with BM, more frequently found inthose with > 10 BM (40%). In the case-control group, OS was 30 % in the case group with BM compared to the control group 64 % (p-value <0.01).

Discussion: Fractures are rare and bone-related pain treatment is needed in 14 % of patients with BM. Presence of > 5 BM is associated with shorter OS and increased risk of carcinoid heart disease. The presence of BM also impair the prognosis, compared to control patients with comparable abdominal metastastic burden.