Innovative issues in clinical cytopathology:quality matters

Bij klinische cytopathologie worden in tegenstelling tot de histopathologie geen cellen in weefselverband beoordeeld, maar losse cellen afkomstig van allerlei organen en lichaamsholten. Kwaliteitsborging en -controle binnen dit subspecialisme zijn blijvend noodzakelijk om aanpassingen en verbeteringen in de toekomst te kunnen verwezenlijken. Dit geheel bestaat uit meerdere categorieën, zoals kwaliteitsaspecten bij het verkrijgen van het celmateriaal, het verwerken van celmateriaal, kritische evaluatie van de toepassing van nieuwe technieken op celmateriaal, de cytodiagnostische vaardigheden, de verslaglegging en de klinische relevantie van cytologische diagnostiek. In dit proefschrift werden een aantal van deze categorieën onderzocht. Zo werd in het kader van controle op verkrijging van celmateriaal de kans op fout-positieve cytologische uitslagen door contaminatie van het werkkanaal van een endoscoop onderzocht. Dit gebeurde bij stadiëringen van patiënten met slokdarmkanker. In het kader van verwerken van celmateriaal en kritische evaluatie van de toepassing van nieuwe technieken werd een alternatieve dunne laag methode van baarmoederhalsuitrijkjes bestudeerd, werd de waarde van een nieuwe celblok methode onderzocht en werd bekeken of het mogelijk is om urine cytologisch te beoordelen door middel van computer-ondersteund screenen. Tot slot werd de klinische relevantie van cytologische diagnostische follow-up van goedaardige nodulaire schildklier afwijkingen geëvalueerd. Deze studie toonde dat het verantwoord is om na een initiële goedaardige cytologische diagnose uit echo-geleid verkregen representatief FNA celmateriaal en na bespreking van de patiënt, liefst in het multidisciplinaire overleg, alleen dan vervolg FNA’s te laten verrichten wanneer bij patiënten klinische of radiologische veranderingen in de schildklierafwijkingen worden gezien.As in other pathology practices quality control and improvement are of utmost importance in clinical cytology. Only critical and objective evaluation of our professional performance will result in quality improvement. In clinical cytology quality control can be divided in several main categories like specimen collection, handling of the cell material, quality of diagnostic skills, and reporting. In this thesis we have focused on several aspects of quality control and improvement in all these categories. As a project in the evaluation of specimen collection, we investigated the procedures involved in endoscopic ultrasound fine needle aspiration of celiac lymph nodes which was part of the staging procedure of patients with esophageal cancer. Secondly, we assessed the accuracy of an alternative low cost liquid based cytology method for the use of cervical scrapings, followed by the exploration of the effectiveness of a new automated cell block processor, the Cellienttm as an innovative project in handling specimens. A comparative study on the accuracy of reading urine samples using computer analyzed screening with conventional cytopathology was performed as part of our efforts to improve urine cytodiagnostic skills. Finally, we addressed the diagnostic value and cost considerations of repeated FNA of solitary thyroid nodules primarily diagnosed as benign nodules

Feasibility of endometrial sampling by vaginal tampons in women with Lynch syndrome

Background: Endometrial sampling for the surveillance of women with Lynch syndrome is an invasive and painful procedure. The aim of this study was to evaluate the feasibility of a less invasive procedure of collecting vital cells by vaginal tampons. Methods: This was a prospective feasibility study of women scheduled to undergo annual gynecological surveillance, including endometrial sampling. We included consecutive asymptomatic women with Lynch syndrome or first-degree relatives and asked them to insert a vaginal tampon 2-4 h before attending their outpatient appointment. Feasibility was evaluated by the following metrics: Patient acceptance, pain intensity of each procedure (assessed by visual analog scale; range 0-10), and the presence of vital cells obtained by tampon-based or endometrial sampling methods. Two pathologists independently evaluated all samples. Results: In total, 25 of 32 approached women completed the tampon-based procedure, with 23 of these subsequently undergoing invasive endometrial sampling. The median visual analog scale scores for tampon use and invasive endometrial sampling were 0 (range, 0-10) and 5.5 (range, 1-10) (p < 0.001). None of the tampon samples analyzed by cytology showed endometrial cells, but they did contain vital squamous cells and granulocytes. By contrast, 18 (78%) of the invasive endometrial samples contained enough endometrial tissue for analysis. No endometrial abnormalities were found by endometrial sampling. Conclusions: Tampon-based endometrial surveillance was a well-accepted and non-painful procedure, and although tampons contained vital cells, they did not provide endometrial cells. However, this study was limited to asymptomatic women with Lynch syndrome (no endometrial pathology), indicating that research is needed to evaluate whether the tampon method has any utility for endometrial surveillance in women with Lynch syndrome

Association of homozygous variants of STING1 with outcome in human cervical cancer

DNA-sensing receptor Cyclic GMP-AMP Synthase (cGAS) and its downstream signaling effector STimulator of INterferon Genes (STING) have gained significant interest in the field of tumor immunology, as a dysfunctional cGAS-STING pathway is associated with poor prognosis and worse response to immunotherapy. However, studies so far have not taken into account the polymorphic nature of the STING-encoding STING1 gene. We hypothesized that the presence of allelic variance in STING1 would cause variation between individuals as to their susceptibility to cancer development, cancer progression, and potential response to (immuno)therapy. To start to address this, we defined the genetic landscapes of STING1 in cervical scrapings and investigated their corresponding clinical characteristics across a unique cohort of cervical cancer patients and compared them with independent control cohorts. Although we did not observe an enrichment of particular STING1 allelic variants in cervical cancer patients, we did find that the occurrence of homozygous variants HAQ/HAQ and R232H/R232H of STING1 were associated with both younger age of diagnosis and higher recurrence rate. These findings were accompanied by worse survival, despite comparable mRNA and protein levels of STING and numbers of infiltrated CD8(+) T cells. Our findings suggest that patients with HAQ/HAQ and R232H/R232H genotypes may have a dysfunctional cGAS-STING pathway that fails to promote efficient anticancer immunity. Interestingly, the occurrence of these genotypes coincided with homozygous presence of the V48V variant, which was found to be individually associated with worse outcome. Therefore, we propose V48V to be further evaluated as a novel prognostic marker for cervical cancer

European experience with the Afirma Gene Expression Classifier for indeterminate thyroid nodules:A clinical utility study in the Netherlands

Background: The Gene Expression Classifier (GEC) and Genomic Sequencing Classifier (GSC) were developed to improve risk stratification of indeterminate nodules. Our aim was to assess the clinical utility in a European population with restrictive diagnostic workup. Methods: Clinical utility of the GEC was assessed in a prospective multicenter cohort of 68 indeterminate nodules. Diagnostic surgical rates for Bethesda III and IV nodules were compared to a historical cohort of 171 indeterminate nodules. Samples were post hoc tested with the GSC. Results: The GEC classified 26% as benign. Surgical rates between the prospective and historical cohort did not differ (72.1% vs. 76.6%). The GSC classified 59% as benign, but misclassified six malignant lesions as benign. Conclusion: Implementation of GEC in management of indeterminate nodules in a European country with restrictive diagnostic workup is currently not supported, especially in oncocytic nodules. Prospective studies with the GSC in European countries are needed to determine the clinical utility.</p

Towards in vivo characterization of thyroid nodules suspicious for malignancy using multispectral optoacoustic tomography

Purpose: Patient-tailored management of thyroid nodules requires improved risk of malignancy stratification by accurate preoperative nodule assessment, aiming to personalize decisions concerning diagnostics and treatment. Here, we perform an exploratory pilot study to identify possible patterns on multispectral optoacoustic tomography (MSOT) for thyroid malignancy stratification. For the first time, we directly correlate MSOT images with histopathology data on a detailed level. Methods: We use recently enhanced data processing and image reconstruction methods for MSOT to provide next-level image quality by means of improved spatial resolution and spectral contrast. We examine optoacoustic features in thyroid nodules associated with vascular patterns and correlate these directly with reference histopathology. Results: Our methods show the ability to resolve blood vessels with diameters of 250 μm at depths of up to 2 cm. The vessel diameters derived on MSOT showed an excellent correlation (R2-score of 0.9426) with the vessel diameters on histopathology. Subsequently, we identify features of malignancy observable in MSOT, such as intranodular microvascularity and extrathyroidal extension verified by histopathology. Despite these promising features in selected patients, we could not determine statistically relevant differences between benign and malignant thyroid nodules based on mean oxygen saturation in thyroid nodules. Thus, we illustrate general imaging artifacts of the whole field of optoacoustic imaging that reduce image fidelity and distort spectral contrast, which impedes quantification of chromophore presence based on mean concentrations. Conclusion: We recommend examining optoacoustic features in addition to chromophore quantification to rank malignancy risk. We present optoacoustic images of thyroid nodules with the highest spatial resolution and spectral contrast to date, directly correlated to histopathology, pushing the clinical translation of MSOT.</p

Clinical Validation of the Cervista HPV HR Test According to the International Guidelines for Human Papillomavirus Test Requirements for Cervical Cancer Screening

This study demonstrates that both the clinical sensitivity and specificity of the Cervista HPV HR test for high-risk human papillomavirus (HPV) detection are not inferior to those of the Hybrid Capture 2 (HC2) test. The intra- and interlaboratory reproducibilities of Cervista were 92.0% (kappa, 0.83) and 90.4% (kappa, 0.80), respectively. The Cervista HPV HR test fulfills all the international HPV test requirements for cervical primary screening purposes

Introduction of primary screening using high-risk HPV DNA detection in the Dutch cervical cancer screening programme:a population-based cohort study

Background: In January 2017, the Dutch cervical cancer screening programme transitioned from cytomorphological to primary high-risk HPV (hrHPV) DNA screening, including the introduction of self-sampling, for women aged between 30 and 60 years. The Netherlands was the first country to switch to hrHPV screening at the national level. We investigated the health impact of this transition by comparing performance indicators from the new hrHPV-based programme with the previous cytology-based programme. Methods: We obtained data from the Dutch nationwide network and registry of histo- and cytopathology (PALGA) for 454,573 women eligible for screening in 2017 who participated in the hrHPV-based programme between 1 January 2017 and 30 June 2018 (maximum follow-up of almost 21 months) and for 483,146 women eligible for screening in 2015 who participated in the cytology-based programme between 1 January 2015 and 31 March 2016 (maximum follow-up of 40 months). We compared indicators of participation (participation rate), referral (screen positivity; referral rate) and detection (cervical intraepithelial neoplasia (CIN) detection; number of referrals per detected CIN lesion). Results: Participation in the hrHPV-based programme was significantly lower than that in the cytology-based programme (61% vs 64%). Screen positivity and direct referral rates were significantly higher in the hrHPV-based programme (positivity rate: 5% vs 9%; referral rate: 1% vs 3%). CIN2+ detection increased from 11 to 14 per 1000 women screened. Overall, approximately 2.2 times more clinical irrelevant findings (i.e. ≤CIN1) were found in the hrHPV-based programme, compared with approximately 1·3 times more clinically relevant findings (i.e. CIN2+); this difference was mostly due to a national policy change recommending colposcopy, rather than observation, of hrHPV-positive, ASC-US/LSIL results in the hrHPV-based programme. Conclusions: This is the first time that comprehensive results of nationwide implementation of hrHPV-based screening have been reported using high-quality data with a long follow-up. We have shown that both benefits and potential harms are higher in one screening round of a well-implemented hrHPV-based screening programme than in an established cytology-based programme. Lower participation in the new hrHPV programme may be due to factors such as invitation policy changes and the phased roll-out of the new programme. Our findings add further to evidence from trials and modelling studies on the effectiveness of hrHPV-based screening