Surgical Outcomes of Colorectal Cancer Surgery for ≥ 85-year-old Patients in Our Hospital: Retrospective Comparison of Short- and Long-term Outcomes with Younger Patients

Objectives: To evaluate future problems in colorectal cancer surgery for elderly patients. Methods: We conducted a retrospective review of patients receiving colorectal cancer surgery in our hospital from January 2010 to December 2018. Patients were divided into the >= 85-year-old patient group and the younger patient group. We compared patient backgrounds, surgical outcomes (surgical procedure, reduction of lymph node dissection range, operative duration, and blood loss), postoperative short-term outcomes (mortality, morbidity, and postoperative length of stay) and prognosis. Results: We performed colorectal cancer surgery on 1,240 patients during the study period. Of them, 109 (8.7%) were >= 85 years old, and 1,131 (91.2%) were < 85 years old. The American Society of Anesthesiologists physical status (ASA-PS) was significantly poorer in the elderly group than in the younger group and patients with a history of cardiac disease and anticoagulant use were significantly more in the elderly group. The rate of reduction of lymph node dissection range was significantly higher in the elderly group (16.8% vs. 3.8%, p < 0.05). Overall morbidity was significantly higher in the elderly group (42.2% vs. 21.9%, p < 0.05), as were the respective frequencies of pneumonia and thromboembolism (8.2% vs. 0.7%, p < 0.05 and 3.6% vs. 0.8%, p < 0.05, respectively). Postoperative hospital stay was significantly longer in the elderly group (17 vs. 12 days, p < 0.05). Overall survival was significantly lower in the elderly group (p < 0.05), but relapse-free survival and colorectal cancer-specific survival were not statistically different between the groups (p = 0.05 and p = 0.15, respectively). Conclusions: Prevention of postoperative pneumonia and thromboembolism remains a problem. After proper assessment and careful management of peri-operative surgical risks, surgery can be indicated in elderly patients.