Prevalence of non 16/18 high risk human papilloma virus as a quality metric in gynecological cytology.

Human papillomavirus (HPV) is the most common sexually transmitted pathogen that causes anogenital disease. Cervical screening by cytology and HPV testing (co-testing) are important in prevention of cervical cancer. The Bethesda System category of atypical squamous cells (ASC) is used when a neoplastic process cannot be confidently identified. In such cases, the differential diagnosis is broad and includes benign conditions. Monitoring of ASC/SIL ratio is a commonly used laboratory quality assurance measure to prevent over- or under-use of this category. High risk human papillomavirus (hr-HPV) has been used in conjunction with the ASC/SIL ratio in determining whether a particular pathologist is over/under-using the indefinite category. However, the laboratory overall sample population prevalence rate of hr-HPV subtypes has not been previously examined for association with the ASC rate. In this study, the relationships between ASC/SIL ratio and hr-HPV prevalence rate and hr-HPV subtypes (16/18 and non-16/18) to the laboratory ASC prevalence were studied. The results demonstrate that HPV non-16/18 is the main subtype which is associated with ASC-US category. A large proportion of non-16/18 HPV-related cases are seen in young patients, which largely abates by the by fourth decade. In addition, there are differences in the ASC/SIL ratio for HPV 16/18 and non-16/18 types. The overall ASC/SIL ratio is an average of the ASC/SIL rate for the non-16/18 population and the HPV 16/18 population. Instead of basing the laboratory and practitioners' quality indicator solely on ASC/SIL ratio, the overall prevalence of HPV and its subtype ratio should also be reported as they are more reflective of laboratory performance.

Classical Hodgkin Lymphoma Presenting as a Sigmoid Mass.

Primary classical Hodgkin lymphoma (CHL) in the colon is exceedingly rare and shares many histologic features with other lymphoproliferative disorders in the gastrointestinal tract. Here we report a case of CHL forming a sigmoid mass. An elderly man with a past medical history of mantle cell lymphoma presented with constipation. Imaging revealed an ulcerated, circumferential mass in the sigmoid colon. Endoscopic biopsy of the mass showed ulcerated colonic mucosa with an underlying diffuse mixed inflammatory infiltrate admixed with Hodgkin and Reed-Sternberg cells. Immunohistochemistry was performed to characterize these cells. They were weakly positive for Pax-5, strongly positive for CD30, variably positive for CD15, and negative for CD45, CD20, CD3, and SOX-11. In situ hybridization was positive for Epstein-Barr virus (EBV) and negative for cytomegalovirus or herpes simplex virus. This immunophenotype is diagnostic for CHL in the clinical context of a large mass. It is not possible in this case to determine whether this is de novo CHL or progression from a precursor lesion like EBV-positive mucocutaneous ulcer. Since diagnosis, this patient underwent colectomy followed by chemotherapy and has remained in complete remission.

Negative loop electrosurgical excision procedure (LEEP) following cervical biopsy diagnosis of high grade squamous intraepithelial lesion.

CONTEXT: Loop Electrosurgical Excision Procedure (LEEP) is commonly performed after cervical biopsy diagnosis of high grade squamous intraepithelial lesion (HSIL/CIN2 or CIN 3). Histological and immunohistochemical assessments are made to differentiate reactive and metaplastic changes from dysplastic changes. A Human Papillomavirus (HPV) test is used for prognostic assessment after conization. OBJECTIVE: We retrospectively reviewed cases where the cervical biopsy showed HSIL but the LEEP specimen was negative for high grade dysplasia. Our aim was to determine the cause of miscorrelation. DATA: IRB approval was obtained and a search was made of all LEEP specimens received during 2018. We reviewed 25 of 137 LEEP specimens that did not correlate with the diagnosis of HSIL rendered on the cervical biopsy. These were from women between 25 to 54 years. All cases had positive high-risk HPV with 80% being non16/18 subtype. On review, 8/25 had HSIL with the remainder of cases falling short of HSIL diagnosis. Follow up cytology with HPV test after the LEEP procedure was negative in all but one case of LSIL with persistent non-16/18 HPV. CONCLUSION: The study highlights the diagnostic difficulties of distinguishing HSIL from immature squamous metaplasia. The practical implication is that in cases with non-16/18 high risk HPV which have thin epithelium and fall short of definite morphologic criteria of HSIL, presence of immature squamous metaplasia should be carefully evaluated. The specific role of CK7 and CK17 which highlight squamocolumnar junctional cells and metaplastic cells, respectively, needs to be explored in these cases.