Moderate dose intraoperative and external beam radiotherapy for locally recurrent rectal carcinoma.

Abstract

Late adverse effects (i.e. neuropathy, chronic bowel obstruction) limit the effective dose given in intraoperative radiotherapy (IORT) and external beam radiotherapy (EBRT). Initial results of a multi-modality treatment approach using moderate dose IORT and moderate dose EBRT are presented. Thirty-one consecutive patients with recurrent rectal carcinomas had IORT and EBRT after complete (R0, n = 14) or incomplete resection (R1, n = 9; R2, n = 8). The mean [ORT dose was 13.7 Gy (range 12-20 Gy) supplemented with an EBRT dose of 41.4 Gy. Twenty-two patients had preoperative EBRT and 22 patients had concomitant chemotherapy (5-FU, Leucovorine). After a median follow-up of 28 months, 16 patients had re-recurrent disease and 11 patients had died. Nine patients failed locally (four in-field, four marginal and one anastomotic re-recurrence), three combined with distant metastasis, resulting in overall and IORT infield local control rates of 71% and 87%, respectively. Distant metastases alone were found in seven patients. The 4-year overall and relapse-free survival rates were 58% and 48%, respectively. After incomplete resection the local failure rate increased (R0 21%, R1/2 35%) and the 4-year relapse-free survival rate decreased significantly (29% versus 71%) due to a markedly increased distant metastasis rate (53% versus 7%). Acute and late toxicities were not increased. The combination of moderate dose IORT and EBRT is a safe and efficacious component in a multi-modality treatment approach.