Comprehensive Genomic Profiling for Therapeutic Decision and Identification of Gene Mutation in Uterine Endometrial Dedifferentiated Carcinoma

Endometrial dedifferentiated carcinoma is a new concept among endometrial malignancies, is rare, and has a poor prognosis as it is discovered in advanced stages and has no established treatment. It has higher rates of gene mutations, such as mismatch repair, than general endometrial cancer and has been associated with Lynch syndrome. However, due to its heterogeneity, case-by-case searches are needed. Comprehensive genomic profiling by Foundation One® CDx can comprehensively identify over 300 gene mutations via a next-generation sequencer and can evaluate biomarkers, such as the microsatellite status and tumor mutation burden. Therefore, it may be beneficial in identifying therapeutic targets and drugs for diseases whose treatment has not been established. In this case, 13 therapies, including immune checkpoint inhibitor therapy for microsatellite instability-High and 40 clinical trials for several gene mutations might be beneficial. We report a case of endometrial dedifferentiated carcinoma for which Foundation One® CDx gene profiling was used to propose treatment.