Thirty-eight patients with Stage I and II uterine carcinosarcoma were treated by surgery with and without whole-pelvic irradiation (WPI) at our institution from 1975 to 1993. Ten patients (8 Stage I and 2 Stage II) were treated with surgery alone, while 28 patients (20 Stage I and 8 Stage II) received WPI in addition to surgery. With a median follow-up of 75 months (range 25-220 months), a trend toward a decreased rate of pelvic recurrence in those receiving WPI (6/28, 21%) compared to those treated with surgery alone (5/10, 50%) was observed (P = 0.09). There was no difference in the rate of distant recurrence between those receiving WPI (12/28, 43%) and those who did not (4/10, 40%) (P = 0.9). There was also no difference in the 2- and 5-year Kaplan-Meier survival estimates for the patients receiving WPI (79 and 59%, respectively) compared to those who did not receive WPI (60 and 60%, respectively) (P = 0.84). In this small series, the addition of whole-pelvic irradiation to primary surgery did not improve survival; however, a trend toward improved pelvic control was observed, suggesting a possible benefit for pelvic irradiation that should be studied in future trials.