The Results of Postoperative Radiation Therapy in the Rectal Cancer / 대한암학회지

ABSTRACT

PURPOSE: This study was designed to evaluate the prognostic factors, survival rate and local recurrence rate of the patients with rectal cancer who received postoperative radiation therapy. METHODS & MATERIALS Seventy patients with rectal cancer received postoperative radiation therapy after curative surgery at the Department of Therapeutic Radiology, Kangnam St. Mary's Hospital, Catholic University Medial College between May 1984 and April 1993. Of the seventy patients, sixty-four evaluable patients were analysed retrospectively. There were 34 men and 28 women. Age at diagnosis ranged from 23 to 74 years. The distribution of stage according to the modified Astler-Coller (MAC) system was as follow 12 in B2+3, 2 in C1, and 50 in C2+3. Postoperative adjuvant therapy included pelvic radiotherapy in all cases and chemotherapy in addition in 55 cases. A total dose of 45 to 60 Gy (median dose 55.8Gy) was delivered in a period of 5 to 6 weeks and the follow-up period ranged from 26 to 133 months with a median of 55 months. RESULTS: Overall two-year and five-year actuarial survival rate were 70.3% and 51.4%, 90.9% and 90.9% in stage B2+3, and 68.2% and 53.6% in stage C. Local failure occurred in 13 (20.3%) of the 64 patients and distant failure rate was 18.8% (12/64). Severe late complication was small bowel obstruction in 4 patients and surgery was required in 3 patients (5%). The significant prognostic factors were stage (p=0.0019) and histologic differentiation (p=0.0046). CONCLUSION: This study suggested a potential adjuvant role for radiation. However, the possible reduction in local failure rates in this study compared with historic control groups must be verified in randomized trial.