A gynecologic oncology group randomized phase III trial of whole abdominal irradiation (WAI) vs. cisplatin-ifosfamide and mesna (CIM) as post-surgical therapy in stage I–IV carcinosarcoma (CS) of the uterus

Abstract Purpose After initial surgery, there has been no established consensus regarding adjunctive therapy for patients with uterine carcinosarcoma (CS). This study was designed to compare patient outcome following treatment with adjuvant whole abdominal irradiation (WAI) versus (vs.) chemotherapy for patients with this rare group of female pelvic malignancies. Patients and methods Eligible, consenting women with stage I–IV uterine CS, no more than 1 cm postsurgical residuum and/or no extra-abdominal spread had their treatments randomly assigned as either WAI or three cycles of cisplatin (C), ifosfamide (I), and mesna (M). Results 232 patients were enrolled, of whom 206 (WAI = 105; CIM = 101) were deemed eligible. Patient demographics and characteristics were similar between arms. FIGO stage (both arms) was: I = 64 (31%); II = 26 (13%); III = 92 (45%); IV = 24 (12%). The estimated crude probability of recurring within 5 years was 58% (WAI) and 52% (CIM). Adjusting for stage and age, the recurrence rate was 21% lower for CIM patients than for WAI patients (relative hazard [RH] = 0.789, 95% confidence interval [CI]: (0.530–1.176), p = 0.245, 2-tail test). The estimated death rate was 29% lower among the CIM group (RH = 0.712, 95% CI: 0.484–1.048, p = 0.085, two-tail test). Conclusion We did not find a statistically significant advantage in recurrence rate or survival for adjuvant CIM over WAI in patients with uterine CS. However, the observed differences favor the use of combination chemotherapy in future trials.