Adjuvant Postoperative Radiotherapy for Adenocarcinoma of the Rectum and Rectosigmoid

Results are presented of a retrospective study on 178 patients receiving adjuvant postoperative radiotherapy after curative surgery for adenocarcinoma of the rectum and rectosigmoid. Tumorstages according to Gunderson-Sosin were B2: 67, B3: 5, C1: 9, C2: 94, and C3: 3. Median total dosage was 50 Gy (range: 10-66 Gy), with a median dose per fraction of 2.0 Gy, 5 fractions per week. The censored overall 5-year survival rate was 42%, and 5-year disease-free survival rate was 37%. The respective rates for stage B2 patients (n = 67) were 59% and 53%, and for stage C2 patients (n = 94), 25% and 25%. Recurrences occurred in 89% within 3 years, 8% in the fourth, and 1% in the fifth year of follow-up. Five-year local relapse rates were 27% for the stage B2 tumors and 40% for the stage C2 tumors. For survival, stage (P = .006), grade (P = .02), fixation at surgery (P = .03), and gender (P = .03) were independent prognostic factors. With local relapse-free probability (LRFP) as endpoint, grade (P < .02) was an independent prognostic factor. Dose of radiation was not of prognostic significance, neither for survival (P = .63) nor for LRFP (P = .61). Since improvement should be made in locoregional control, initiatives are taken to start preoperative radiotherapy; furthermore, the key role of surgery is emphasized.