To Örebro University

OBJECTIVE: With the transition from cytology to human papilloma virus (HPV) testing in cervical cancer screening, it is possible to use self-sampling instead of professionally collected samples. Most studies have included women between 20 and 60 years age. Here we aimed to study postmenopausal women and investigate whether vaginal self-sampling is equally effective as professional sampling for detection of HSIL and the possibility to use a method for molecular triage directly on the screening sample.

METHODS: Postmenopausal women in Örebro county, Sweden, were invited (n = 7835) during 2018-2020 to participate in the study including both professional and self-sampling. In total 2258 women returned both sample types, that were analyzed for HPV followed by triage for cytology, HPV genotyping and methylation and clinical follow-up according to national guidelines.

RESULTS: The prevalence of HPV was 3.4 % in the professionally collected samples and 12.6 % in the self-collected. All women with high-grade squamous intraepithelial lesion (HSIL) were HPV-positive in both professionally and self-collected samples. For self-collected samples, we compared different triage strategies. Cytology was the most efficient strategy. Among the molecular triage methods, the combination of methylation and genotyping was most efficient but resulted in twice as many colposcopy referrals as cytology.

CONCLUSIONS: In conclusion, HPV self-sampling with molecular triage detects HSIL to the same extent as professional screening with cytological triage. The specificity of molecular triage is, however, unacceptably low, and to avoid overtreatment other triage methods following primary self-sampling need to be developed.

Vulvar cancer is a rare gynaecological disease that can be caused by infection with human papillomavirus (HPV). The mutational frequencies and landscape for HPV-associated and HPV-independent vulvar tumor development are supposedly two distinctly different pathways and more detailed knowledge on target biological mechanisms for individualized future treatments is needed. The study included formalin-fixed paraffin-embedded (FFPE) samples from 32 cancer patients (16 HPV-negative and 16 HPV-associated), treated in Örebro, Sweden from 1988 to 2008. The Oncomine™ Comprehensive Assay v3 was used to detect variants across 161 different tumor relevant genes. Data analysis included quality assessment followed by variant analysis of DNA with the Oncomine Comprehensive v3 workflow and with a custom filter using the VarSome Clinical software. The RNA-analysis was performed with the Oncomine Comprehensive v3 workflow. Totally, 94% of DNA libraries and 81% of RNA libraries were of adequate quality for further downstream analysis. With the Oncomine™ filter chain there was an increased number of variants in the HPV-negative group (2.5 variants) compared to the HPV-associated group (1.5 variants). Using custom filter and the Varsome Clinical software; additional single nucleotide variants (SNV) were detected where the vast majority were classified as likely benign/benign. HPV-negative tumors had a larger fraction of variants of unknown significance (VUS), and likely pathogenic/pathogenic compared to the HPV-associated tumours. The top 10 frequently mutated genes in HPV-indepentent tumors were TP53, POLE, PTCH1, BRCA2, CREBBP, NOTCH2, ARID1A, CDKN2A, MSH2, and NOTCH1. Three fusion genes were detected; TBL1XR1(1)::PIK3CA(2) (n = 2) and NF1(5)::PSMD11(2) (n = 1). Copy number variations (CNV) were more common in HPV-associated tumors (n = 13/16, 81%) compared to HPV-negative tumors (n = 9/14, 64%). The most frequent CNV was found in the cMYC gene, followed by CDK2 (n = 5) and CDK4 (n = 4). The main outcome of this study show that vulvar cancer harbour genetic variations of different types and specifically, HPV-independent tumours are molecularly very heterogeneous and harboured more SNVs while HPV-associated tumors more frequently presented with gene amplifications. The PI3K/AKT/mTOR1 pathway was affected in both the groups as well as the cell cycle regulation pathway. Similarly, the DNA repair gene POLE was found mutated in both vulvar cancer groups.

We aimed to investigate the use of free glycosaminoglycan profiles (GAGomes) and cfDNA in plasma to differentiate between lung cancer and benign lung disease, in a cohort of 113 patients initially suspected of lung cancer. GAGomes were analyzed in all samples using the MIRAM® Free Glycosaminoglycan Kit with ultra-high-performance liquid chromatography and electrospray ionization triple quadrupole mass spectrometry. In a subset of samples, cfDNA concentration and NGS-data was available. We detected two GAGome features, 0S chondroitin sulfate (CS), and 4S CS, with cancer-specific changes. Based on the observed GAGome changes, we devised a model to predict lung cancer. The model, named the GAGome score, could detect lung cancer with 41.2% sensitivity (95% CI: 9.2-54.2%) at 96.4% specificity (95% CI: 95.2-100.0%, n = 113). When we combined the GAGome score with a cfDNA-based model, the sensitivity increased from 42.6% (95% CI: 31.7-60.6%, cfDNA alone) to 70.5% (95% CI: 57.4-81.5%) at 95% specificity (95% CI: 75.1-100%, n = 74). Notably, the combined GAGome and cfDNA testing improved the sensitivity, compared to cfDNA alone, especially in ASCL stage I (55.6% vs 11.1%). Our findings show that plasma GAGome profiles can enhance cfDNA testing performance, highlighting the applicability of a multiomics approach in lung cancer diagnostics.

BACKGROUND: The aim of this study was to examine the natural course of HPV infection in women of 60 years and older who were HPV positive at inclusion, and any association between HPV positivity in historical samples and dysplasia outcome. METHODS: Eighty-nine women aged 60-82 years, who tested positive for HPV between 2012 and 2016 were included. Sampling for cytology and/or histology was also performed. HPV genotyping was carried out on archived material back to 1999.

RESULTS: Of the 89 HPV-positive women 16 had HSIL, 34 had LSIL and 39 were benign at inclusion. Of the women with HSIL, 50.0% had the same HPV type in the archive samples, 12.5% had another type, and 37.5% were HPV negative. Among the 34 women with LSIL, 47.1% had the same HPV type in archive samples, 5.8% had another type, and 47.1% were HPV negative. Of the 39 women without dysplasia at inclusion, 25.6% had the same HPV type in archive samples, 5.1% had another HPV type and 69.2% were HPV negative.

CONCLUSION: Surprisingly few of the elderly women thus seem to have a history with the same or any HPV infection the years before being diagnosed with an HPV infection and dysplasia. The significance of an HPV infection for dysplasia development in elderly women is still not fully understood.

BACKGROUND: Human papillomavirus (HPV) has emerged as a significant contributor to cancer incidence globally, particularly in the context of oropharyngeal squamous cell carcinoma (OPSCC) and cancer of unknown primary (HNCUP). This study aimed to develop and validate droplet digital PCR (ddPCR) assays for the detection of circulating tumor HPV DNA (ctHPV-DNA) in plasma, focusing on high-risk HPV genotypes associated with these cancers.

METHODS: ddPCR assays for HPV16, 18, 33, 35, 56, and 59 were developed and tested using gBlocks, HPV cell-free DNA, fragmented tumor HPV+ DNA, and plasma samples from patients with HPV+ OPSCC (n = 110) and HNCUP (n = 9).

RESULTS: Assays demonstrated robust technical sensitivity across all tested HPV genotypes. Clinical application of the assays on a cohort of patients with HPV+ OPSCC and HNCUP revealed high sensitivity (91.6%) and wide variability in ctHPV-DNA levels. Analyses revealed correlations between ctHPV-DNA levels and TNM stage and tumor viral load. The association between ctHPV-DNA and tumor viral load persisted even after adjusting for TNM stage. At posttreatment, 72.5% of samples had reached undetectable ctHPV-DNA levels. Having detectable ctHPV-DNA posttreatment was associated with a higher ctHPV-DNA level at diagnosis and higher viral load at diagnosis.

CONCLUSION: The findings underscore the potential of ctHPV-DNA as a biomarker for monitoring HPV+ cancers and offer insights into tumor dynamics. Implementation of these assays in clinical practice could enhance no-invasive treatment monitoring and recurrence detection in HPV-associated cancers.

CLINICAL TRIALS: NCT05904327.

BACKGROUND: With HPV screening the specificity of screening positives has decreased, even with a cytological triage test. Increases in colposcopies and detection of benign or low-grade dysplasia are reported, not least in older women. These results highlight the necessity to find other triage tests in HPV screening strategies, so that women can be more accurately selected for colposcopy, thus minimizing the clinically irrelevant findings.

METHODS: The study included 55- to 59-year-old women who exited the screening with normal cytology, but later in a follow-up test were positive for the HPV genotypes 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66 and 68 and had a cervical cone biopsy done. To model a screening situation with hrHPV-positive women, three different triage strategies, namely, cytology, genotyping and methylation, were performed. The study considered the effect of direct referral to colposcopy for HPV genotypes 16, 18, 31, 33, 45, 52 and 58, and methylation for FAM19A4 and hsa-mir124-2 and/or any form of abnormal cytology.

RESULTS: Seven out of 49 women aged 55-59 years with hrHPV had a cone biopsy with high-grade squamous intraepithelial lesion. No triage method found all cases, and when comparing positive and negative predictive value and false negative rate, cytology showed better results than genotyping and methylation.

CONCLUSION: This study does not support a switch in triage strategies from cytology to hrHPV genotyping and methylation for women above 55 years of age yet, but demonstrates the need for more evidence on molecular triage strategies.

Background: Patients with non-small cell lung cancer (NSCLC) harboring a ROS proto-oncogene 1 (ROS1)-rearrangement respond to treatment with ROS1 inhibitors. To distinguish these rare cases, screening with immunohistochemistry (IHC) for ROS1 protein expression has been suggested. However, the reliability of such an assay and the comparability of the antibody clones has been debated. Therefore we evaluated the diagnostic performance of current detection strategies for ROS1-rearrangement in two NSCLC-patient cohorts.

Methods: Resected tissue samples, retrospectively collected from consecutive NSCLC-patients surgically treated at Uppsala University Hospital were incorporated into tissue microarrays [all n=676, adenocarcinomas (AC) n=40 1, squamous cell carcinomas (SCC) n=2 13, other NSCLC n=62]. ROS1rearrangements were detected using fluorescence in situ hybridization (FISH) (Abbott Molecular; ZytoVision). In parallel, ROS1 protein expression was detected using IHC with three antibody clones (D4D6, SP384, EPMGHR2) and accuracy, sensitivity, and specificity were determined. Gene expression microarray data (Affymetrix) and RNA-sequencing data were available for a subset of patients. NanoString analyses were performed for samples with positive or ambiguous results (n=21).

Results: Using FISH, 2/630 (0.3% all NSCLC; 0.5% non-squamous NSCLC) cases were positive for ROS1 fusion. Additionally, nine cases demonstrated ambiguous FISH results. Using IHC, ROS1 protein expression was detected in 24/665 (3.6% all NSCLC; 5.1% non-squamous NSCLC) cases with clone D4D6, in 18/639 (2.8% all NSCLC; 3.9% non-squamous NSCLC) cases with clone SP384, and in 1/593 (0.2% all NSCLC; 0.3% non-squamous NSCLC) case with clone EPMGHR2. Elevated RNA-levels were seen in 19/369 (5.1%) cases (Affymetrix and RNA-sequencing combined). The overlap of positive results between the assays was poor. Only one of the FISH-positive cases was positive with all antibodies and demonstrated high RNA-expression. This rearrangement was confirmed in the NanoString-assay and also in the RNA sequencing data. Other cases with high protein/RNA-expression or ambiguous FISH were negative in the NanoString-assay.

Conclusions: The occurrence of ROS1 fusions is low in our cohorts. The IHC assays detected the fusions, but the accuracy varied depending on the clone. The presumably false-positive and uncertain FISH results questions this method for detection of ROS1-rearrangements. Thus, when IHC is used for screening, transcript-based assays are preferable for validation in clinical diagnostics.

Swedish guidelines recommend cervical screening with primary HPV for women ≥ 30 years of age. The aim of this study was to compare an implemented HPV cervical screening programme in the Region of Örebro County from September 1, 2016, with the former cytology-based screening programme.

The clinical effectiveness by means of number of high-grade squamous intraepithelial lesions (HSILs) and cervical cancer cases detected in histology within 12 months after the screening test, together with cost implications were the main outcomes. Data were retrieved from the Swedish National Cervical Screening Registry between the years 2014-2015 (cytology based screening) and 2017-2018(HPV based screening), including screening information such as invitations and cytology and histology diagnoses.

The detection rate of HSIL + among women ≥ 30 years of age was 1.2 times higher with HPV screening, but data revealed an increase in direct colposcopy referral rate by 54% and a higher percentage of irrelevant findings (≤LSIL). Screening based on HPV for women ≥ 30 has increased yearly cost from 1 to 1.3 million EUR, while increasing the number of HSIL + identified. Two thirds of the total costs are from visits for screening samples in the programme.

HPV screening detected more cases of HSIL + compared to cytology screening among women ≥ 30 although high colposcopy rate, high rate of clinical irrelevant findings and higher costs were shown in the HPV-based screening programme, which implies that alterations in the screening programme in the future are important to consider.

Microsatellite instability is characterised by gains or losses of nucleotides in short tandem repeat sequences, microsatellites, dispersed throughout the human genome. Microsatellite instability status is a molecular fingerprint for DNA mismatch repair deficiency. Clinical detection of microsatellite instability status is important for identifying inherited disease in patients with colorectal and endometrial cancer but has also a prognostic value for survival and prediction of treatment response. Lately, microsatellite instability has been used as a tumor agnostic biomarker that predicts response to immune checkpoint inhibitors. To identify microsatellite instability status clinically, PCR and immunohistochemistry have been the gold standard. On the contrary, next generation sequencing provide simultaneous accession of large number of microsatellite loci and can be combined with detection of several other biomarkers. 

The national collaboration Genome Medicine Sweden have developed a solid tumour gene panel composed of 560 cancer associated genes with integrated microsatellite instability score. Our aim was to validate the microsatellite instability status based on microsatellite instability score from GMS560 DNA panel against the clinically used methods. Extracted DNA (100 ng) from formalin fixed paraffin embedded tissue sections with various tumour cell content >10% were analysed. During target enrichment sequencing analysis, allelic distribution from 5000 microsatellite markers were calculated by MSIsensor Pro to generate an instability score. 

The cohort consisted of microsatellite instable verified colorectal cancer samples (n=20), microsatellite stable solid tumour material (n=60). Preliminary results generated a microsatellite instability score for the colorectal cancer samples with a mean of 26.5 % (CI: 23.4-29.6, range: 16.9-32.3). Microsatellite stable tumour samples had a mean microsatellite instability score of 1.5 % (CI: 0.93-2.07, range: 1-4.45). 

In conclusion, we found the microsatellite instability score from GMS560 DNA panel to be both diagnostically sensitive and specific for determining MSI status due to obvious separation in instability. 

Currently, cervical cancer prevention is undergoing comprehensive development regarding human papillomavirus (HPV) vaccination and cervical cancer screening. In Sweden and many other countries, high coverage vaccinated cohorts are entering screening within the next few years. This entails demands for baseline HPV genotype data across the screening age range for surveillance and a basis for screening program adjustment. In 2016, Örebro County, Sweden, changed to primary HPV screening using HPV mRNA testing followed by cytology triage. An alternative triage method to cytology could allow for a fully molecular screening algorithm and be implemented in a screening program where self-sampling is included. Hypermethylation analysis of the human genes FAM19A4/miR124-2 has been suggested as a promising triage method. HPV mRNA-positive screening samples (n = 529) were included and subjected to genotyping targeting a broad range of both low-risk and high-risk genotypes in addition to hypermethylation analysis of the two human genes FAM19A4/miR124-2. Data were connected to cytological and histological status and age. The most commonly detected genotypes were HPV31, 16, and 52. In addition, HPV18 was one of the most common genotypes in high-grade squamous intraepithelial lesions (HSILs) samples. In relation to available vaccines, 26% of the women with histological HSIL or cancer (≥HSIL) tested positive for only hrHPV included in the quadrivalent vaccine and 77% of the genotypes in the nonavalent vaccine. According to these figures, a relatively large proportion of the HSILs will probably remain, even after age cohorts vaccinated with the quadrivalent vaccine enter the screening program. Hypermethylation positivity was associated with increasing age, but no HPV-related independently predictive factors were found. Accordingly, age needs to be considered in development of future screening algorithms including triage with hypermethylation methodology.