Lynch Syndrome Screening of Women with Endometrial Cancer: Feasibility and Outcomes in a Community Program.

OBJECTIVE: Universal screening of endometrial cancer for underlying Lynch syndrome (LS) using DNA mismatch repair immunohistochemistry (MMR IHC) has been recommended. The objective of this study was to assess the feasibility and outcomes of using office endometrial samplings in a community LS screening program. METHODS: A community laboratory adopted Cancer Care Ontario's LS screening recommendations. All new endometrial cancers in women aged <70 years were screened for LS using MMR IHC and MLH1 promoter methylation testing cascade for MLH1/PMS2-deficient cases. This retrospective validation study analyzes the first year's results. RESULTS: Of 693 new endometrial cancers, 467 (67.4%) were eligible for LS screening. Both MMR IHC and MLH1 promoter methylation testing were conclusive in >98% of cases. MMR deficiency (MMRd), which includes LS screen-positive cases, was identified in 25.9% of patients (121/467). LS screen-positive tumours comprised 5.9% (27/467) of all cases. CONCLUSION: Endometrial samplings from community practice are suitable for pre-operative LS screening. This testing can identify MMRd endometrial cancers with significant prognostic implications. Approximately 1 in 20 Ontario women <70 years of age with endometrial cancer screen positive for LS. Pre-operative and/or operative assessment for co-existent colonic neoplasms needs to be considered in this high-risk group. In addition, these women should be referred to genetic counselling.

Approaches for triaging women who test positive for human papillomavirus in cervical cancer screening.

Substantial evidence exists to support the introduction of molecular testing for human papillomavirus (HPV) as the primary technology in cervical cancer screening. While HPV testing is much more sensitive than cytology for detection of high-grade precancerous lesions, it is less specific. To improve efficiency, it is therefore recommended that a specific test (like cytology) be used in triaging HPV positive women to colposcopy. A number of studies have been conducted that support the use of cytology alone or in conjunction with HPV genotyping for triage. The decision to incorporate genotyping also depends on the commercial HPV test that is selected since not all tests provide results for certain individual high-risk types. Regardless of whether policy officials decide to adopt a triage approach that incorporates genotyping, the use of liquid based cytology (LBC) may also improve screening performance by reducing diagnostic delays. With LBC, the same cell suspension from a single collection may be used for HPV testing and a smear can be immediately prepared if HPV status is positive. This was a critical lesson from a community based demonstration project in Montreal (VASCAR study), where conventional cytology exists and specimen co-collection was not permitted for ethical reasons, requiring HPV positive women to return for an additional screening visit prior to colposcopy.

Introduction of molecular HPV testing as the primary technology in cervical cancer screening: Acting on evidence to change the current paradigm.

Since being introduced in the 1940s, cervical cytology - despite its limitations - has had unequivocal success in reducing cervical cancer burden in many countries. However, we now know that infection with human papillomavirus (HPV) is a necessary cause of cervical cancer and there is overwhelming evidence from large-scale clinical trials, feasibility studies and real-world experience that supports the introduction of molecular testing for HPV as the primary technology in cervical cancer screening (i.e., "HPV primary screening"). While questions remain about the most appropriate age groups for screening, screening interval and triage approach, these should not be considered barriers to implementation. Many countries are in various stages of adopting HPV primary screening, whereas others have not taken any major steps towards introduction of this approach. As a group of clinical experts and researchers in cervical cancer prevention from across Canada, we have jointly authored this comprehensive examination of the evidence to implement HPV primary screening. Our intention is to create a common understanding among policy makers, agencies, clinicians, researchers and other stakeholders about the evidence concerning HPV primary screening to catalyze the adoption of this improved approach to cervical cancer prevention. With the first cohort of vaccinated girls now turning 21, the age when routine screening typically begins, there is increased urgency to introduce HPV primary screening, whose performance may be less adversely affected compared with cervical cytology as a consequence of reduced lesion prevalence post-vaccination.