•In a bleeding postmenopausal woman with didelphys uterus, endometrial biopsy should be taken from both uterine cavities.•Sentinel lymph node mapping has not been previously described in the setting of endometrial cancer and uterine didelphys.•Routine sentinel lymph node mapping was successfully performed in a patient with endometrial cancer and uterine didelphys.
Case report: Sentinel lymph node mapping of endometrial carcinoma occurring in uterine didelphys.