Endometrial stromal sarcoma in combination with mixed type endometrial carcinomas

RATIONALE Endometrial stromal sarcoma (ESS) is rare, representing only approximately 0.2% of all uterine malignancies. Mixed type endometrial carcinomas (MT-ECs) are rare tumors with both type I and II features, and are difficult to diagnose. Cases of ESS and MT-ECs coexisting in the same patient are extremely rare. This study aimed to describe a case of ESS in combination with MT-ECs in a 47-year-old premenopausal woman. PATIENT CONCERNS A woman presented to the hospital complaining of occasional abdominal pain and had high tumor markers: cancer antigen (CA) 19-9 (263.6 U/mL) and CA 125 (428.0 U/mL). Transvaginal ultrasound examination revealed a complex mass (12.3 × 9.1 × 6.3 cm) with solid and cystic components on the right rear wall of the uterus. Abdominopelvic computed tomography images showed a pelvic cystic-solid mixed mass. The patient underwent an exploratory midline laparotomy. The mass was hypothesized to be malignant on the uterine posterior wall. Tumor deposits were found on bilateral parametrium. On peritoneal implantation, multiple metastases were seen on the serosal surface of the bowel and greater omentum. A frozen section revealed a spindle cell sarcoma. DIAGNOSES Pathological reports following surgery revealed concurrent ESS and MT-ECs. INTERVENTIONS The patient underwent a total abdominal hysterectomy, bilateral salpingo-oophorectomy, total omentectomy, and macroscopic clearance of the tumor. Adjuvant chemotherapy was given. OUTCOMES The patient was still alive when this report was written. LESSONS Considering the rarity of ESS in combination with MT-ECs, this study presented an overview of the literature and discussed a number of histological and clinical issues. Nevertheless, etiology and pathogenesis of these tumors need further investigation.