Histological interpretation of differentiated vulvar intraepithelial neoplasia (dVIN) remains challenging-observations from a bi-national ring-study

Differentiated vulvar intraepithelial neoplasia (dVIN) is a premalignant lesion that is known to progress rapidly to invasive carcinoma. Accurate histological diagnosis is therefore crucial to allow appropriate treatment. To identify reliable diagnostic features, we evaluated the inter-observer agreement in the histological assessment of dVIN, among a bi-national, multi-institutional group of pathologists. Two investigators from Erasmus MC selected 36 hematoxylin-eosin-stained glass slides of dVIN and no-dysplasia, and prepared a list of 15 histological features of dVIN. Nine participating pathologists (i) diagnosed each slide as dVIN or no-dysplasia, (ii) indicated which features they used for the diagnosis, and (iii) rated these features in terms of their diagnostic usefulness. Diagnoses rendered by > 50% participants were taken as the consensus (gold standard). p53-immunohistochemistry (IHC) was performed for all cases, and the expression patterns were correlated with the consensus diagnoses. Kappa statistics were computed to measure inter-observer agreements, and concordance of the p53-IHC patterns with the consensus diagnoses. For the diagnosis of dVIN, overall agreement was moderate (= 0.42), and pair-wise agreements ranged from slight (= 0.10) to substantial (= 0.73). Based on the levels of agreement and ratings of usefulness, the most helpful diagnostic features were parakeratosis, cobblestone appearance, chromatin abnormality, angulated nuclei, atypia discernable under x 100, and altered cellular alignment. p53-IHC patterns showed substantial concordance (= 0.67) with the consensus diagnoses. Histological interpretation of dVIN remains challenging with suboptimal inter-observer agreement. We identified the histological features that may facilitate the diagnosis of dVIN. For cases with a histological suspicion of dVIN, consensus-based pathological evaluation may improve the reliability of the diagnosis

Evaluation of a nationwide Dutch guideline to detect Lynch syndrome in patients with endometrial cancer

Objective: In the Netherlands a nationwide guideline was introduced in 2016, which recommended routine Lynch syndrome screening (LSS) for all women with endometrial cancer (EC) <70 years of age. LSS consists of immunohistochemical (IHC) staining for loss of mismatch repair (MMR) protein expression, supplemented with MLH1 methylation analysis if indicated. Test results are evaluated by the treating gynaecologist, who refers eligible patients to a clinical geneticist. We evaluated the implementation of this guideline. Methods: From the nation-wide pathology database we selected all women diagnosed with EC < 70 years of age, treated from 1.6.2016–1.6.2017 in 14 hospitals. We collected data on the results of LSS and follow up of cases with suspected LS. Results: In 183 out of 204 tumours (90%) LSS was performed. In 41 cases (22%) MMR protein expression was lost, in 25 cases due to hypermethylation of the MLH1 promotor. One patient was known with a pathogenic MLH1 variant. The option of genetic counselling was discussed with 12 of the 15 remaining patients, of whom three declined. After counselling by the genetic counsellor nine patients underwent germline testing. In two no pathogenic germline variant was detected, two were diagnosed with a pathogenic PMS2 variant, and five with a pathogenic MSH6 variant, in concordance with the IHC profiles. Conclusion: Coverage of LSS was high (90%), though referral for genetic counselling could be improved. Gynaecologists ought to be aware of the benefits and possible drawbacks of knowing mutational status, and require training in discussing this with their patients

Operation experience with a novel highly efficient micro-scale CHP system based on fuel-flexible gasification and a SOFC

An efficient and fuel flexible micro-scale biomass CHP technology based on the combination of a small-scale updraft gasifier with a SOFC system is developed within the project FlexiFuel-SOFC. High load flexibility and a maximum of full load operating hours of the CHP system is achieved by operating the CHP part of the plant with a side stream (product gas extracted from the gasifier) of a heat controlled system (gas burner and boiler as well as heat recovery). A gas cleaning unit (GCU) for the treatment of the side stream according to the requirements for the operation of the SOFC regarding contaminant (H2S, HCl) and TSP removal as well as tar content reduction was designed, constructed and successfully evaluated. A considerable reduction of the gravimetric tar content down to a suitable tar content for the operation of the SOFC stack module is achieved by gasifier internal tar reformation and a further reformation step in the tar reformer of the GCU. Comprehensive tests have been successfully performed with a broad spectrum of solid biomass fuels at a testing plant at BIOS in Graz. Promising test run results showing a basic proof of concept for the new technology could be gained