Analysis of failure patterns in stage III endometrial carcinoma and therapeutic implications

The poor outcome of certain patients with Stage III endometrial carcinoma has led some investigators to direct adjuvant therapy to the abdominal cavity. To better define failure patterns, a review of 126 patients with Stage III endometrial carcinoma treated at four institutions was performed. Seventy-four patients were diagnosed at surgery with pathologic Stage III disease, whereas 52 patients presented with clinical Stage III disease. Most patients received external beam irradiation to the pelvis with a variety of boost techniques. Site of disease, grade, depth of invasion, and pathology were examined for prognostic significance. Actuarial techniques were used to analyze survival and recurrences. For the 52 clinical Stage III patients, 5-year survival was 36%. The median survival of 20 patients who were treated with radiation therapy (RT) following biopsy was 9 months. Pelvic control was poor in these patients, with 16/18 evaluable patients failing locally. Thirty-two patients who underwent resection with adjunctive RT had a 5-year survival of 48%. Local failure occurred in 40% of patients, whereas 38% of patients had abdominal failure. Isolated abdominal failure was infrequent with 6% failing as isolated recurrence, and 16% failing as the only site of distant disease. For 74 pathologic Stage III patients, 5-year survival was 54%. Local failure resulted in 20% of patients, and isolated abdominal failure occurred in 7% of patients. The subset of patients with ovarian or tubal involvement included 42 patients, with a 5-year survival of 60%. Further analysis of this subset by grade and depth of myometrial penetration was found to be prognostically significant. Twenty-four patients who were Stage III because of parametrial or pelvic peritoneal involvement had a 5-year survival of 44%. Local control and survival is improved in Stage III patients treated with surgical resection. The high rate of distant metastases in both abdominal and extra-abdominal sites has significant therapeutic implications.