Abstract
AIM: To evaluate the long-term outcome of standard 5-FU based adjuvant or neoadjuvant radiochemotherapy and to identify the predictive factors, especially anemia before and after radiotherapy as well as hemoglobin increase or decrease during radiotherapy. METHODS: Two hundred and eighty-six patients with Union International Contre Cancer (UICC) stage II and III rectal adenocarcinomas, who underwent resection by conventional surgical techniques (low anterior or abdominoperineal resection), received either postoperative (n=233) or preoperative (n=53) radiochemotherapy from January 1989 until July 2002. Overall survival (OAS), cancer-specific survival (CSS), disease-free survival (DFS), local-relapse-free (LRS) and distant-relapse-free survival (DRS) were evaluated using Kaplan-Meier, Log-rank test and Cox's proportional hazards as statistical methods. Multivariate analysis was used to identify prognostic factors. Median follow-up time was 8 years. RESULTS: Anemia before radiochemotherapy was an independent prognostic factor for improved DFS (risk ratio 0.76, P=0.04) as well as stage, grading, R status (free radial margins), type of surgery, carcinoembryonic antigen (CEA) levels, and gender. The univariate analysis revealed that anemia was associated with impaired LRS (better local control) but with improved DFS. In contrast, hemoglobin decrease during radiotherapy was an independent risk factor for DFS (risk ratio 1.97, P=0.04). During radiotherapy, only 30.8% of R0-resected patients suffered from hemoglobin decrease compared to 55.6% if R1/2 resection was performed (P=0.04). The 5-year OAS, CSS, DFS, LRS and DRS were 47.0%, 60.0%, 41.4%, 67.2%, and 84.3%, respectively. Significant differences between preoperative and postoperative radiochemotherapy were not found. CONCLUSION: Anemia before radiochemotherapy and hemoglobin decrease during radiotherapy have no predictive value for the outcome of rectal cancer. Stage, grading, R status (free radial margins), type of surgery, CEA levels, and gender have predictive value for the outcome of rectal cancer.