Radiation and chemotherapy instead of surgery for low infiltrative rectal adenocarcinoma: a prospective trial

The objective of this prospective study was to determine the possibility of treatment based exclusively on chemotherapy and radiotherapy for patients with low infiltrative rectal tumors in an attempt to preserve sphincter function.

Sixteen patients with rectal adenocarcinoma up to 3 cm above the pectineal line with initial indications for abdominoperineal resection (APR) were submitted to a 5040-cGy (28 x 180 cGy) radiotherapy dose and chemotherapy during the first 3 and last 3 days of radiotherapy, using 425 mg/m2/day of 5-fluorouracil (5FU) and 20 mg/m2/day of folinic acid. Levamisole was used at 150 mg/day for 3 consecutive days at 2-week intervals throughout the period of therapy. Patients with a complete response were not submitted to APR, but received additional brachytherapy for curative purposes with doses from 2000 to 3000 cGy. Patients with recurrence after a complete response, with partial response, or with no response were submitted to APR.

Six patients (37.5%) presented a complete response, five (31.25%) presented a partial response, and five (31.35%) did not respond. The disease-free interval ranged from 1 to 34 months (mean = 11 months) among the six patients with complete response, and only one patient not submitted to APR is currently asymptomatic. Among the 15 patients with an indication for APR, three refused surgery because of full improvement of clinical symptoms and currently have tumor activity in the rectum. Mean patient follow-up was 23.8 months (8 to 43 months), and ten patients (62.5%) showed no evidence of active disease at last follow-up.

The therapeutic schedule used was not effective in preserving sphincter function in patients with low infiltrative rectal adenocarcinoma, because responses, although very frequent, were only temporary.