Lost opportunities for mismatch repair (MMR) screening among minority women with endometrial cancer

Abstract Lynch Syndrome (LS) prevalence in underrepresented minorities are lacking. The objective of this study was to assess the prevalence of LS in a minority patient population. Secondary objectives included identifying factors associated with successful LS screening and to characterize clinicopathologic features. Women with endometrial cancer treated within a university system from 2014 and 2016 were included. Immunohistochemistry (IHC) results of MLH1, PMS2, MSH2 and MSH6 were obtained from medical records and clinicopathologic factors abstracted. Patients not previously screened for LS were screened. 276 patients were evaluable. More minority women were screened as part of their routine cancer care (p = 0.005). Additionally, women 50 years or younger were more likely to be screened for LS compared to women older than 51(p = 0.009) and uninsured or reliant on Medicaid patients (p = 0.011) were more likely to be screened during routine care. Six patients received confirmatory germline testing for LS (4.3%), and another 8 patients had a staining pattern suggestive of LS. In an underrepresented population, the rate of LS in endometrial cancer is similar to previous reports. LS may be under diagnosed and opportunities missed when universal screening is not applied in minority women.