Long-term results of 1-week intravaginal high-dose-rate brachytherapy alone for endometrial cancer

OBJECTIVE
To compare the biologic equivalence in terms of local control and toxicity of a short course of high-dose-rate intravaginal brachytherapy alone (IVBa) delivered over five consecutive days (25 Gy/5 Rx/5 days) to other more protracted classical schemes 21 Gy/3 Rx/14-28 days (Postoperative Radiation Therapy in Endometrial Carcinoma [PORTEC]-2/Memorial Sloan-Kettering Cancer Center).

METHODS AND MATERIALS
From February 2001 to May 2008, 122 patients with International Federation of Gynecology and Obstetrics Stage IaG3-IIIaG2 endometrial adenocarcinoma were treated with total abdominal hysterectomy and bilateral salpingo-oophorectomy followed by postoperative IVBa. Seventy-seven patients (63.1%) underwent surgical staging. Total IVBa dose was 25Gy in five consecutive daily fractions prescribed at 0.5-cm depth.

RESULTS
After a median followup of 4.1 years, the rates of Radiation Therapy Oncology Group Grades 1, 2, and ≥3 complications were 12.9%, 3.4%, and 0.8%, respectively. Five patients (4.1%) presented locoregional failures: two isolated nodal pelvic failures, one vaginal pelvic relapse (intra-abdominal lymph node metastases), one vaginal distant failure, and one combined locoregional and distant failure. The 8.5-year actuarial vaginal control rate was 97.5%, and the pelvic control rate was 94.3%. Six other patients developed distant metastases alone. The 8.5-year actuarial overall and disease-free survival rates were 90.3% and 87.2%, respectively. Univariate analysis revealed that histologic grade, deep myometrial invasion, advanced age, and categorization as high intermediate-risk patient according to the PORTEC-2 and the Gynecologic Oncology Group (GOG)-99 stratifications were statistically significant prognostic factors. After multivariate analysis, histologic grade (p=0.001) and high intermediate risk according to GOG-99 (p=0.004) and PORTEC-2 (p=0.001) remained significant.

CONCLUSIONS
The proposed scheme reproduces the excellent results obtained with more protracted schemes and has the added advantage of shortened overall treatment time.

CITA DEL ARTÍCULO Brachytherapy. 2012 Mar;11(2):119-24