Best of Best Poster Oral Clinical Oncology Society of Australia Annual Scientific Meeting 2019

Colorectal cancer in older adults: frequency of major resection and surgical outcomes (#216)

David E Theile 1 , Philippa Youl 2 , John Harrington 2 , Danica Cossio 2 , Nathan Dunn 3
  1. Queensland Cancer Control Safety and Quality Partnership, Queensland Health, Brisbane, Queensland, Australia
  2. Queensland Cancer Control Analysis Team, Queensland Health, Brisbane, QLD, Australia
  3. Queensland Cancer Control Analysis Team, Cancer Alliance Queensland, Brisbane, Queensland, Australia

Aims: Colorectal cancer (CRC) is one of the most common cancers diagnosed in Australia. With an ageing population the incidence of CRC in older adults continues to increase. The predominant treatment for invasive CRC is surgical resection, however these procedures can be complex. We conducted a population-based review of major resection in older adults in Queensland.

Methods: The Queensland Oncology Repository (QOR) collates and matches patient-level administrative and clinical data from the Queensland Cancer Register together with public and private hospital admissions, pathology, radiology, treatment, and mortality data. Adults aged 65+years diagnosed with CRC between 2007-2016 were identified using QOR. We examined major resection rates, 30- and 90-day post-operative mortality and two-year survival. In addition, we examined factors associated with the likelihood of having major resection along with factors associated with risk of post-operative mortality using multivariate modelling.

Results: Of 18,591 adults aged 65+ years 76.8% (n=14,270) had a major resection for CRC. Patients were less likely to have a major resection if they were male (OR=0.88, 95%CI=0.82-0.95); lived in an area of disadvantage (OR=0.75, 95%CI=0.66-0.86) or a remote/very remote location (OR=0.66, 95%CI=0.52-0.85). Compared to those aged 65-69 years, the likelihood of major resection decreased significantly with increasing age (p <0.001). We observed a significant reduction in 30- and 90-day post-operative mortality over time. Over time, reductions in 30-day mortality were observed for those aged 65-69 years (p=0.002) and 80-84 years (p=0.02).  Two-year survival improved from 78.2% in 2007-2011 to 80.8% from 2012-2016 (p <0.001). Improvements in survival were evident across all age groups except for patients aged 85+ years.

Conclusions: We found three-quarters of adults aged 65+ years received a major resection for CRC. The post-operative mortality reductions and improved survival observed for all older age groups over time likely reflect improvements in surgical procedures and post-operative care.