Outcomes following major resection for colorectal cancer in patients aged 65+ years: a population-based study in Queensland, Australia.

ABSTRACT

BACKGROUND: The risk of developing colorectal cancer (CRC) increases with increasing age. As surgery is the primary treatment for CRC, our aim was to examine outcomes following major resection for CRC in a cohort of individuals aged ≥65 years. METHODS: This population-based retrospective study included 18 339 patients aged ≥65 years diagnosed with CRC from 2007 to 2016. Multivariate logistic regression was used to examine factors associated with the likelihood of having major resection, 30-day mortality and laparoscopic surgical procedure. Cox proportional hazards was used to examine factors associated with risk of death at 2 years post-surgery. RESULTS: Overall, 77.8% (n = 14 274) of patients had a major resection. Males and patients ≥75 years were significantly less likely to have a major resection (P < 0.001 and P < 0.001, respectively). Thirty-day mortality was 3.1% and 2-year overall survival was 78.7%. After adjustment, factors such as increasing age (≥75 years), ≥2 comorbidities, emergency admission, open surgical procedure and treatment in a public hospital were all independently and significantly associated with poorer outcomes. The likelihood a patient had a laparoscopic procedure was significantly lower for those from a disadvantaged area (P < 0.001), emergency admission (P < 0.001) as well as for those treated in a public versus private hospital (P < 0.001). CONCLUSIONS: Post-operative mortality increased, and 2-year survival decreased after age 75 years. The finding of significantly lower rates of laparoscopic surgery for patients from disadvantaged areas and those treated in a public hospital requires further investigation.