BACKGROUND: The authors undertook this study to test the hypothesis that perioperative blood transfusion has an adverse effect on survival of patients with colorectal cancer. METHODS: A retrospective analysis was performed on 725 patients who underwent curative resection for Dukes Stage B and C colorectal cancers in our institution between 1981-1985 and who were followed for 5-11 years. RESULTS: Rectal cancers occurred more frequently in the transfused than in the nontransfused patients (64% versus 47%; P = 0.0001). In the patients with colon cancer, no significant effect of transfusion on recurrence-free survival was seen (P = 0.8, log-rank; P = 0.49, Cox regression analysis). The cumulative 5-year survival rate was 77% (95% confidence interval, 69-85%) for the nontransfused and 78% (72-83%) for the transfused patients. In patients with rectal cancer, the 5-year survival rate was 79% (67-87%) for the nontransfused and 67% (59-71%) for the transfused patients. A significant association was noted in patients with Stage B cancer (P = 0.002, log-rank; P = 0.02, Cox regression analysis), but not in those with Stage C cancer (P = 0.05, log-rank; P = 0.15, Cox regression analysis). In patients with Stage B rectal cancer, more frequent abdominoperineal resections (APR) were performed among the transfused patients (65% versus 32%; P = 0.0001). This subgroup was further stratified by operative procedure and reanalyzed using the same Cox regression model. Transfusion had no effect on survival of patients treated by APR (P = 0.31) or of those having a sphincter-saving procedure (P = 0.53). CONCLUSION: The seemingly adverse effect of perioperative blood transfusion on the survival of patients with colorectal cancer may be explained by other covariates.
BACKGROUND: The authors undertook this study to test the hypothesis that perioperative blood transfusion has an adverse effect on survival of patients with colorectal cancer. METHODS: A retrospective analysis was performed on 725 patients who underwent curative resection for Dukes Stage B and C colorectal cancers in our institution between 1981-1985 and who were followed for 5-11 years. RESULTS:Rectal cancers occurred more frequently in the transfused than in the nontransfused patients (64% versus 47%; P = 0.0001). In the patients with colon cancer, no significant effect of transfusion on recurrence-free survival was seen (P = 0.8, log-rank; P = 0.49, Cox regression analysis). The cumulative 5-year survival rate was 77% (95% confidence interval, 69-85%) for the nontransfused and 78% (72-83%) for the transfused patients. In patients with rectal cancer, the 5-year survival rate was 79% (67-87%) for the nontransfused and 67% (59-71%) for the transfused patients. A significant association was noted in patients with Stage B cancer (P = 0.002, log-rank; P = 0.02, Cox regression analysis), but not in those with Stage C cancer (P = 0.05, log-rank; P = 0.15, Cox regression analysis). In patients with Stage B rectal cancer, more frequent abdominoperineal resections (APR) were performed among the transfused patients (65% versus 32%; P = 0.0001). This subgroup was further stratified by operative procedure and reanalyzed using the same Cox regression model. Transfusion had no effect on survival of patients treated by APR (P = 0.31) or of those having a sphincter-saving procedure (P = 0.53). CONCLUSION: The seemingly adverse effect of perioperative blood transfusion on the survival of patients with colorectal cancer may be explained by other covariates.