Endocavitary irradiation. An option in select patients with rectal cancer

Endocavitary irradiation delivers high-dose irradiation with limited penetration and is an established modality for the curative treatment of select tumors. The purpose of this study was to review the experience from our institution with endocavitary irradiation.

All patients with rectal cancer treated with endocavitary irradiation between 1973 and 1992 were studied. Collected data included: tumor size, tumor differentiation, distance from the anal verge, mean follow-up, recurrence, and other treatments used.

One hundred ninety-nine patients received endocavitary irradiation, with 126 treated with curative intent. No significant differences were found between groups with recurrence and no recurrence when examining tumor size, differentiation, distance from the anal verge, or follow-up. With a mean time to recurrence of 16.1 (range, 1-56) months, 37/126 patients had a recurrence, and 89/126 had no recurrence. Ten recurrences were distant, and all patients died of the disease. Twenty-seven patients had local recurrence. Following additional treatments, 14 additional patients were rendered free of disease.

Endocavitary irradiation initially rendered 71 percent (89/126) free of disease. With additional treatment 11 percent (14/126) were rendered free of disease. In the subgroup of patients followed more than five years, 68 percent had no evidence of disease at follow-up after endocavitary irradiation, and 91 percent had no evidence of disease with additional treatment. Tumor size, differentiation, morphology, and distance from the anal verge did not influence recurrence. Debulking or surgical excision before endocavitary irradiation did not increase recurrence. Diligent long-term follow-up and a liberal policy to biopsy suspicious areas may increase the salvage rate.