Unexpected Histopathological Diagnosis of Undifferentiated Uterine Sarcoma after Simple Hysterectomy: Extrapolating Limited Evidence

Uterine sarcomas are a rare malignancy, often retrospectively diagnosed after myomectomy or hysterectomy. Undifferentiated uterine sarcomas (UUS) are a particularly aggressive variant of this condition. Little evidence exists regarding the postoperative management of undifferentiated sarcomas diagnosed after hysterectomy performed for presumed benign conditions. We describe the case of a 33-year-old woman who presented with heavy bleeding and subsequently underwent hysterectomy on an emergency basis after failed medical management. Cut-section of the uterus revealed a grossly benign-looking sub-mucosal fibroid. However, the final histopathology report revealed undifferentiated uterine sarcoma. We worked up the patient postoperatively with MRI to rule out metastasis and performed bilateral salpingo-oophorectomy based on hormone receptivity status. We followed this with single-agent chemotherapy with adriamycin, which was followed by continuous therapy with oral letrozole (aromatase inhibitor). The patient was found doing well at the two-year follow-up, with no evidence of relapse. Postoperative diagnosis of UUS should include imaging to rule out metastasis, consideration for completion of surgery based on hormone receptivity of tumour, and lymphadenectomy based on the subtype of tumour.