Does Antiplatelet Therapy Affect Short-Term and Long-Term Outcomes of Patients Undergoing Surgery for Colorectal Cancer? - Surgical Radicality Versus Perioperative Antiplatelet-Related Morbidity Risks

BACKGROUND: The effect of antiplatelet therapy(APT) on short-term and long-term outcomes in patients receiving surgery for colorectal cancer is still unknown. METHODS: A total of 491 patients undergoing surgery for colorectal cancer between 2005 and 2011 were reviewed. The perioperative management protocol(“Kokura Protocol”) included preoperative continuation of aspirin monotherapy and early postoperative reinstitution in patients at high thromboembolic risks. Both short-term and long-term outcomes of patients with APT (n=148), including perioperative morbidity, disease free survival (DFS) and overall survival (OS), were compared to those of patients without APT (n=343). RESULTS: Among 148 patients with APT, none suffered from excessive hemorrhage intraoperatively. There were only 4 postoperative bleeding complications(0.8%) and 1 thromboembolic event(0.2%), and operative mortality was zero. In the APT and non-APT groups, 5-year DFS rates were 75.5% and 77.7%(P=0.207), respectively; 5-year OS rates were 68.8% and 78.9%(P=0.004), respectively. OS rates were lower in APT group compared with non-APT group, but multivariate analysis showed that APT was not a significant factor for either DFS or OS. CONCLUSIONS: The resection of colorectal cancer in patients with APT was performed safely, and satisfactory long-term outcome was obtained without any decrease of surgical radicality. The Kokura Protocol is valid and feasible to secure both short-term and long-term outcomes of such patient population.