Doxorubicin as an adjuvant following surgery and radiation therapy in patients with high-risk endometrial carcinoma, stage I and occult stage II: A Gynecologic Oncology Group study

The Gynecologic Oncology Group studied the use of adjuvant doxorubicin after surgery and radiation therapy for endometrial carcinoma in a randomized, prospective manner. The study population consisted of patients clinically stage I or II (occult) who, after surgical-pathologic evaluation, had one or more risk factors for recurrence: greater than 50% myometrial invasion, pelvic or aortic node metastasis, cervical involvement, or adnexal metastases. All patients without aortic node metastasis received 5000 rads to the whole pelvis at 160-180 rads per day. If aortic node metastasis was documented, aortic field radiation to the top of T12 was offered. The aortic target dose was 4500 rads at 150 rads per day. After completion of radiation therapy, the patients were randomized to receive doxorubicin bolus therapy (60 mg/m² starting dose) to a maximum cumulative dose of 500 mg/m². Between November 1977 and July 1986, 92 patients were entered into the doxorubicin (DOX) treatment arm, and 89 patients entered the no-DOX arm. There was no statistically significant difference in survival or progression-free interval of the two arms. The 5-year survival rates for patients with deep myometrial invasion, cervical involvement, and pelvic node metastases were similar (63-70%), whereas the rate for patients with aortic node metastases was 26%. There was no significant difference in the recurrence pattern between the two treatment arms. There were no cases of grade 3 or 4 cardiac toxicity. Twelve patients (6.9%) developed small bowel obstruction after radiation therapy. There were three treatment-related deaths in the DOX arm and two in the radiation therapy-only arm. We conclude that, because of protocol violations, small sample size, and the number of patients lost to follow-up, this study was unable to determine what effect use of doxorubicin as adjuvant therapy had on recurrence, progression, and survival of the endometrial cancer study population. The combination of surgical staging and postoperative radiation as used in this study appears to increase the risk of bowel complications.