[Retroperitoneal mixed malignant mullerian tumor : exceptional localisation and prognosis]

Primary retroperitoneal carcinosarcoma or mixed malignant mullerian tumor (MMMT) is an extremely rare clinical entity. These aggressive tumors arise most commonly from genital tract. The retroperitoneal location is exceptional. Here we report the case of a 63-years old female diagnosed with heterologous, extra-genital, retroperitoneal carcinosarcoma, with malignant cells in the ascitic fluid and extra-ovarian metastatic implants. She was treated with complete radical surgical treatment consisting of resection of the retroperitoneal tumor, with omentectomy, hysterectomy, bilateral salpingooophorectomy and lumbo-aortic and pelvic lymphadenectomy. She received adjuvant chemotherapy with 6 cycles of Carboplatin and Paclitaxel. She is in complete clinical and radiological remission since the end of chemotherapy, for a total of 113 months. To our knowledge, this is the longest reported disease free survival of the extra-genital retroperitoneal MMMT. This case and the review of the literature illustrate the importance of surgical treatment. However, there are no evidence-based guidelines for the systemic management of these tumors.