Vaginal cuff HDR brachytherapy alone is sufficient adjuvant treatment for patients with surgical stage I endometrial cancer

Abstract

Adjuvant pelvic external beam radiotherapy (EBRT) has been found to decrease the rate of pelvic and vaginal recurrence after surgery for Stage I endometrial cancer. However, pelvic EBRT may be unnecessary treatment for pathologic Stage I endometrial cancer for patients who undergo complete surgical staging. Because most recurrences after surgery occur at the vaginal cuff, treating the vaginal cuff alone may be sufficiently effective and potentially less toxic than pelvic EBRT. Most adjuvant high dose rate brachytherapy (HDR) studies thus far have included patients without complete surgical staging. The purpose of this study is to determine the efficacy and complication rate of adjuvant HDR brachytherapy alone for patients with Stage I endometrial cancer having undergone complete surgical staging. Between April 1998 and March 2004, 100 patients with Stage I endometrial cancer underwent complete surgical staging (TAH/BSO and pelvic ± para-aortic lymph node sampling) followed by post-operative vaginal cuff HDR brachytherapy at our institution. 73% had endometrioid (or unspecified) adenocarcinoma, 16% had papillary serous carcinoma, and 11% had other histologies (adenosquamous, clear cell, MMT, and mixed histologies). Most patients (94%) were either FIGO IB (N = 54) or IC (N = 40). Five were FIGO IA and 1 had unspecified depth of myometrial invasion. All IA patients were grade III. Of the IB patients, 6, 27, and 20 were grade I, II, and III, respectively. Of the IC patients, 13, 17, and 10 were grade I, II, and III, respectively. One IB patient had unspecified grade and the patient with unspecified substage was grade II. The mean maximum tumor diameter was 3.9 cm. Lymphovascular invasion (LVI) was included in 23% of pathology reports and, of these, 3 patients had LVI. Five patients (all with papillary serous carcinoma) were treated with adjuvant chemotherapy. Typically, 3 HDR fractions x 700 cGy each were delivered to a depth of 5–7mm from the vaginal mucosa using a multiple channel cylinder and Nucletron mHDR afterloading device. All patients had a pelvic lymph node dissection and 42% had a para-aortic node dissection. A median of 29.5 (range, 1–67) pelvic nodes were removed (84% had >10 pelvic nodes removed) and a median of 10.5 (range, 1–35) para-aortic nodes were removed. The mean number of days between the first and last HDR treatments was 14.7. The total dose was 2100 cGy in 95% of patients. With a median follow-up of 23 months (range, 1–62), there were no pelvic or vaginal recurrences. Three patients developed distant metastases. The peritoneal cytology from one patient who developed omental and lung metastases originally had cells suspicious, but not diagnostic, for malignancy. One patient developed retroperitoneal metastases and died. One patient developed peritoneal metastases and is still alive. Two patients died from other causes; one from acute myeloid leukemia that evolved from essential thrombocythemia, and one from an unidentified cause. Thirty-nine percent of patients had no side effects. Most side effects were mild (CTC grade 1–2) and consisted of vaginal cuff telangiectasias (14%), vaginal atrophy, stricture, or adhesions (16%), dyspareunia (5%), temporary urinary irritation (9%), and temporary diarrhea (9%). Four patients had mild intermittent urinary incontinence after treatment, possibly related to surgery, brachytherapy, or other factors. There was one cuff dehiscence from applicator placement that healed spontaneously. Adjuvant HDR brachytherapy alone is effective and has minimal side effects for patients with surgical Stage I endometrial cancer. At our institution, patients underwent an extensive lymph node sampling/dissection and there were no vaginal or pelvic recurrences after vaginal cuff brachytherapy alone. Thus, for similar patients, HDR brachytherapy alone is a safe and effective alternative to pelvic EBRT