Comparison of surgical and oncologic outcomes in very elderly patients (≥ 80 years old) and elderly (65–79 years old) colorectal cancer patients: a propensity score matching

PURPOSE: The purpose of this study was to investigate the short-term outcomes and prognosis of elderly and very elderly colorectal cancer (CRC) patients after primary CRC surgery using propensity score matching (PSM). METHODS: This study retrospectively collected the medical records of CRC patients ≥ 65 years old undergoing primary CRC surgery from Jan 2011 to Jan 2020. Short-term outcomes, overall survival (OS) and disease-free survival (DFS) were compared between very elderly CRC patients (≥ 80 years old) and elderly CRC patients (65–79 years old). RESULTS: A total of 2084 patients were enrolled for analysis. After PSM, 331 very elderly patients were matched to 331 elderly patients. In terms of short-term outcomes, the very elderly patients had longer postoperative hospital stays (p = 0.007) after PSM. In terms of OS, it was found that age (p < 0.01, HR = 1.878, 95% CI 1.488–2.371), tumor stage (p < 0.01, HR = 1.865, 95% CI 1.603–2.170), overall complications (p < 0.01, HR = 1.514, 95% CI 1.224–1.872) and major complications (p = 0.001, HR = 2.012, 95% CI 1.319–3.069) were independent prognostic factors. For DFS, age (p < 0.01, HR = 1.816, 95% CI 1.579–2.088), tumor stage (p < 0.01, HR = 1.816, 95% CI 1.579–2.088), overall complications (p = 0.002, HR = 1.379, 95% CI 1.128–1.685) and major complications (p = 0.002, HR = 1.902, 95% CI 1.259–2.874) were found to be independent prognostic factors. Moreover, elderly patients had a better OS and DFS than very elderly patients. CONCLUSION: Very elderly patients had a poorer prognosis than elderly patients after primary CRC surgery. Surgeons should be cautious when treating very elderly CRC patients.