Factors affecting local control and survival after treatment of carcinoma of the rectum by endocavitary radiation: A retrospective study of 97 cases

Purpose: Endocavitary radiation therapy constitutes an alternative to surgi cal therapy for some early rectal carcinomas. We studied the prognostic fac tors for locoregional or metastatic relapse after endocavitary radiation, a nd their impact for therapeutic strategy. Methods and Materials: Our study reports the outcome of 97 patients with ad enocarcinomas of the rectum treated from 1978 to 1998 by endocavitary irrad iation (100 Gy), exclusive or combined with an interstitial brachytherapy b oost of 20 Gy, The indications consisted mostly of polypoid, mobile tumors, less than 4 cm in diameter, and well differentiated. But the indications w ere extended to elderly patients, who presented with a high surgical risk o r who refused mutilating surgery. Results: The mean follow-up was 82 months. One patient presented with an is olated distant metastatic relapse, and 27 patients presented with locoregio nal recurrence, surgically salvaged in 16 cases. Disease-free survival was 71% at 5 years and 68% at 10 years, Multifactorial analysis suggests that c linical stage T1A, well-differentiated tumors, and early and complete respo nse are favorable prognostic factors for disease-free survival. Response to therapy is the most powerful prognostic factor for relapse. Conclusion: This retrospective study confirms the efficacy of endocavitary radiotherapy combined with brachytherapy as a safe conservative treatment i n well-selected patients. (C) 2001 Elsevier Science Inc.