Influence of cardiopulmonary bypass surgery on cancer-specific survival rate of patients with colorectal cancer

PURPOSE: There is evidence of a relationship between inflammation and cancer growth and spread. Cardiopulmonary bypass surgery is known to induce a systemic inflammatory response. The aim of this study was to determine whether cardiopulmonary bypass surgery influences the cancer-specific survival rate in patients with colorectal cancer. METHODS: The Fremantle Hospital database on patients with colorectal cancer (477 patients) was linked to the Western Australian Hospital Morbidity Database System. Patients who had colorectal cancer after having undergone cardiopulmonary bypass surgery (n = 7) were identified. The cancer-specific survival rate for these patients was compared with that for a group of controls derived from the hospital database. Controls were matched for age, gender, tumor location, tumor stage, operative procedure, and adjuvant therapy (n = 26). RESULTS: The cancer-specific survival rate of the seven patients with colorectal cancer who had undergone cardiopulmonary bypass surgery was significantly lower than that for control patients (5-year survival rate, 34 vs. 71 percent, respectively; P < 0.05; hazard ratio, 2.9; 95 percent confidence interval, 1.5-4.4). Of the two patients in the study group who survived for 18 months, one had liver metastases and the other had local recurrence of a rectal cancer. CONCLUSION: In patients with colorectal cancer, having undergone cardiopulmonary bypass surgery was associated with a reduced cancer-specific survival rate. Additional studies are required to validate this association and explore the possibility of a causal relationship.