Efficacy and toxicity of adjuvant chemotherapy in elderly patients with colon carcinoma - A 10-year experience of the geisinger medical center

BACKGROUND. Although the benefit from adjuvant chemotherapy has been established clearly in patients with Stage III colon carcinoma, the degree to which elderly patients with colon carcinoma can tolerate such therapy generally has remained unknown. METHODS. The authors reviewed all patients in their Tumor Registry with Stage II and Stage III adenocarcinoma of the colon who underwent potentially curative resection for their disease at the Geisinger Medical Center between January 1990 and September 2000. One hundred twenty patients underwent complete resection of their colon carcinoma and received 5-fluorouracil-based (5-FU) adjuvant chemotherapy. RESULTS. The 5-year disease free survival rate for patients age greater than or equal to65 years (Group A) was 70% compared with 56% for patients age < 65 years (Group B) (P = 0.085). The 5-year overall survival rate for patients in Group B was 77% compared with 62% for the patients in Group A (P = 0.143). In a Cox regression model, age was not a predictor of disease free survival (P = 0.633) or overall survival (P = 0.900) when it was analyzed as a continuous variable. Only 19 patients were age > 75 years, and the disease free and overall survival rates for this group were similar but were underpowered compared with the rates for the patients ages between 65-75 years. When gender and disease stage were included in the model, age remained a nonsignificant variable (P = 0.400 for disease free survival; P = 0.615 for overall survival). Nine of 56 patients in Group A (16%) experienced Grade 3-4 toxicity compared with 14 of 64 patients in Group B (22%) (P = 0.420). The lack of a correlation between toxicity and age was maintained after controlling for disease stage and patient gender (P = 0.343). There were no correlations between preoperative carcinoembryonic antigen level, tumor grade, or lymph node involvement and patient age (P = 0.258, P = 0.256, and P = 0.519, respectively). CONCLUSIONS. Elderly patients with Stage II and Stage III colon carcinoma benefit from 5-FU-based adjuvant therapy without a significant increase in toxicity compared with their younger counterparts. Adjuvant chemotherapy should be presented to elderly patients with high-risk, resected colon carcinoma. The data regarding age cannot be generalized to patients age > 75 years.