THE ROLE OF ADJUVANT CHEMORADIOTHERAPY IN THE TREATMENT OF RECTAL CANCER

Purpose: To determine the efficiency of postoperative adjuvant chemoradiotherapy in rectal carcinoma. Material and Methods: Between 1991 and 2000, 185 patients with rectal carcinoma were treated with adjuvant chemoradiotherapy. The median age was 53 (24-74) and male/female ratio was 1.6. The type of the surgery was abdominoperineal resection (APR) in 79 patients (43%) and low anterior resection (LAR) in 106 patients (57%). According to the pathological evaluation, 78 patients (42%) were stage II and 107 patients (58%) were stage III. Histological grade was unknown in 7 patients (4%), grade I in 26 patients (14%), grade II in 121 patients (66%), grade III in 23 patients (12%) and mucineous adenocarcinoma in 8 patients (4%). Postoperatively blood carcinoembriogenic antigen (CEA) and CA 19-9 levels were evaluated in 72 patients (40%) and in 95% of the patients they were found to be in normal limits. As the adjuvant treatment, postoperatively 2 cycles of chemotherapy (CT) (5- Fluorouracil 400 mg/m2+Folinic acid 20 mg/m2) were administered and radiotherapy (RT) (5040 cGy/28 fractions) was started together with the third cycle of chemotherapy. The chemotherapy was completed to six cycles. Results: The median follow-up time was 36 months. Locoregional relapse occurred in 40 patients (22%) and distance metastases were seen in 38 patients (20%). The 5 year overall and disease free survival rates were 60.1 % and 53.7% respectively. In univariate analysis, the pathological stage and the histological grade were found to be statistically significant (p<0.0001 and p=0.02, respectively). In multivariate analysis, the pathological stage was found to be the only significant parameter (p<0.0001). Conclusion: For pathological T3.4 and N+ rectal carcinomas, postoperative adjuvant chemoradiotherapy is the standard treatment regimen. The most important prognostic factor is the pathological stage. The risk of death is 5 times higher for stage III patients than stage II patients.

Keywords: rectal carcinoma, adjuvant, chemoradiotherapy