Endocavitary radiation for rectal adenocarcinoma: 10-year results

Abstract

Purpose: The purpose of this study is to assess local control results, survival, side effects and complications of endocavitary radiation used for early rectal cancers at our institution. Materials and Methods: This study is a retrospective review of the charts of the 35 patients treated with endocavitary radiation for rectal adenocarcinoma between 1987 and 2000 at our institution. Questionnaires were also sent to patients still alive. The age range of the patients was from 44 to 92 years old. 71% of the patients were more than 70 years old at the time of procedure. Median age was 75 years old. Three patients had grade 1 tumors, 28 had grade 2 tumors and 4 had grade 3 tumors. Four tumors were Tis, 6 were T1, 21 were T2, 3 were T3 and the stage was unknown for one. Two of the T3 patients also received external beam radiation and the other one was treated with endocavitary radiation after multiple recurrences. 83% of the patients were treated with curative intent. The reasons for treating patients palliatively were that either they had metastases or they were elderly patients, some with comorbidities, treated for recurrence. Treatment consisted of a total dose of 20 to 155 Gy in one to five fractions with 50 KV x-rays through a treatment proctoscope. Follow-up is between 1 and 163 months (median of 61 months) for the local control issue. Follow-up for the survival endpoint is from 7 to 163 months (median of 102 months). Kaplan-Meier method was used to assess local control and survival rates. Results: Local control was achieved in 23 of the 29 patients treated with curative intent and 3 of the 6 patients treated palliatively. Local control rate at 5 and 10 years is 71%. No local failures occured after 21 months. Local control for patients treated with curative intent is 76% at 5 and 10 years. Survival rate is 56% at 5 years and 36% at 10 years. Median survival is 64 months. Almost 80% of the patients experienced short-term side effects, usually not serious, within 90 days of endocavitary treatment(s). Long-term complications occured in more than 80% of the patients, but were very rarely severe. The most common complications were blood per rectum, diarrhea, urgency, incontinence, constipation, pain, proctitis and ulcer. Only one patient needed a colostomy after perforation subsequent to biopsy of a non-healing ulcer. Conclusion: Endocavitary radiation provides reasonably good local control for early rectal cancer and severe complications seldom occur. This technique is very convenient, requiring only a few fractions of radiation.