Radiation Oncology/Uterine Sarcoma/Overview

Uterine Sarcoma Overview Comprise <1% of GYN malignancies and 2-5% of uterine malignancies Three distinct tissues of origin: Carcinosarcoma (mixed mullerian tumor): endometrium, accounts for 40-50%. High frequency of TP53 mutations. Subtypes: Heterologous type: Sarcomatous components derived from skeletal muscle, cartilage, or bone; frequently rhabdomyosarcomas or chondrosarcomas More aggressive, poorer prognosis, higher risk of recurrence Homologous type: Sarcomatous component derived from endometrium, usually resemble high-grade undifferentiated sarcoma or fibrosarcoma GOG 150: Whole Abdominal Irradiation (WAI) vs Cisplatin-Ifosfamide and Mesna (CIM) as post-surgical therapy 206 patients with uterine carcinosarcoma Stages I-IV eligible as long as no demonstrable parenchymal hepatic involvement or extra-abdominal distant disease All patients underwent TAH, BSO, and maximal resection of all gross intra-abdominal/pelvic disease, including macroscopically involved pelvic and para-aortic nodes, leaving no residual disease any larger than 1 cm WAI: 1 cm margins on the diaphragm superiorly, the inguinal ligament inferiorly, and the lateral aspect of the peritoneal margin laterally; AP/PA; total dose 30 Gy. 20 Gy 4-field boost to true pelvis. CIM: cisplatin (20 mg/m2/day IV × 4 days) that was to be followed by a one hour IV administration of Ifosfamide (1.5 g/m2/day IV × 4 days) with mesna (120 mg/m2 IV bolus over 15 minutes on day one, followed by 1.5 g/m2/day IV continuous infusion × 4 days beginning with day one) every three weeks for three cycles. Primary endpoints: Death and recurrence rates No statistically significant difference in time to recurrence (at 5 years, 58% WAI vs 52% CIM) No statistically significant difference in survival time (at 5 years, 35% WAI vs 45% CIM) Slightly more vaginal recurrences in CIM group and more abdominal recurrences in WAI group, but not statistically significant AEs: Higher grade 3 or 4 acute anemia and neuropathy in CIM group, higher grade 2-4 gastrointestinal events in WAI group. Two WAI patients died of radiation hepatitis. One CIM patient died of acute port infection complicated by neutropenia. Leiomyosarcoma: myometrial muscle, accounts for ~30% Endometrial stromal sarcoma: endometrial stroma, accounts for ~15% Please see more detail at cancer.gov PDQ Shueng et al. (2013) Unusual Oligometastases of Distant Nodes as the Initial Relapse Site of Uterine Sarcoma: A Case Report, Therapeut Radiol Oncol 2013; 20(4): 315-321.