- AIM: Lynch Syndrome (LS) is associated with an increased risk of developing endometrial carcinoma (EC) and ovarian carcinoma (OC). There is considerable variability in current practices and opinions related to screening newly diagnosed patients with EC/OC for LS. An online survey was undertaken to explore the extent of these differences. METHODS: An online questionnaire was developed by a panel of experts and sent to all members of the British Association of Gynaecological Pathologists (BAGP) and the International Society of Gynecological Pathologists (ISGyP). Anonymised results were received and analyzed. RESULTS: Thirty-six BAGP and 44 ISGyP members completed the survey. More than 90% of respondents were aware of the association of LS with both EC and OC, but 34% were not aware of specific guidelines for LS screening. Seventy-one percent of respondents agreed that universal screening for LS should be carried out in all newly diagnosed EC cases, with immunohistochemistry (IHC) alone as the preferred approach. Only 36% of respondents currently performed IHC or microsatellite instability testing on all newly diagnosed EC, with most of the remaining respondents practicing selective screening, based on clinical or pathological features or both. A significant minority of respondents (35%) believed that patient consent was required before performing MMR IHC. Almost all respondents favored use of standardized terminology for reporting MMR staining results and this is proposed herein. CONCLUSION: There is wide support for universal LS screening in patients with EC, but this survey highlights areas of considerable variation in practice.