Purpose: Total-abdominal hysterectomy and bilateral salpingo-oophorectomy (TAHBSO) is the gold-standard therapy for patients with endometrial carcinoma. However, patients with high operative risks are usually treated with radiation therapy (RT) alone. The goal of this study was to update our experience of high-dose-rate brachytherapy (HDRB), with or without external-beam irradiation (EBRT), for such patients.
Methods and materials: Between 1984 and 2003, 38 patients with Stage I and Stage II adenocarcinoma of the endometrium considered high operative risk received RT as the primary treatment. The median age was 74.1 years. Before 1996, the local extent of the disease was assessed by an examination under anesthesia (EUA) and by EUA and magnetic resonance imaging (MRI) thereafter. Eight patients (21%) were treated with combined HDRB and EBRT, and 30 patients (79%) were treated with with HDRB alone. The median HDRB dose was 23.9 Gy, typically delivered in 3 fractions in a weekly schedule. The median EBRT dose was 42 Gy.
Results: At a median follow-up of 57.5 months for patients at risk, 11 patients (29%) have failed: 6 patients (16%) locally, 4 patients (10.5%) distantly, and 1 patient (3%) locally and distantly. Local failure was established by biopsy, and 4 patients were salvaged by TAHBSO. Higher stage and higher grade were both associated with increased failure rate. The 15-year disease-specific survival (DSS) was 78% for all stages, 90% for Stage I, and 42% for Stage II (p < 0.0001). The 15-year DSS was 91% for Grade I and 67% for Grade II and III combined (p = 0.0254). Patients with Stage I disease established by MRI (11 patients) and who received a total HDRB dose of 30 Gy had a DSS rate of 100% at 10 years. Four patients experienced late toxicities: 1 Grade II and 3 Grade III or IV.
Conclusion: Medically inoperable Stage I endometrial carcinoma may be safely and effectively treated with HDRB as the primary therapy. In selected Stage I patients, our results are equivalent to that of surgery. We believe that the alternative option of HDRB as the primary therapy for selected Stage I endometrial carcinoma, even in patients with low operative risks, needs further evaluation.