Abstract
Aims: To review the patterns of early-onset (<50 years old) colorectal cancer (CRC) in Alberta across the past 15 years among different socioeconomic and demographic patient subgroups. Methods: This is a retrospective, population-based study based on Alberta administrative databases. Income level was identified via income information from the 2006 Canadian census. Patients with colorectal adenocarcinoma diagnosed 2004–2018 were included. Frequency analyses were used to examine the percentage of early-onset CRC cases among different subgroups over the period studied. Multivariable logistic regression analysis was used to examine factors associated with the development of early-onset CRC. Results: A total of 24,912 patients were included, of whom 2096 (8.4%) were diagnosed at age <50 years and 22,816 (91.6%) at age ≥50 years. The percentage of patients diagnosed at age <50 years increased over time (10.2% in 2018 vs 7.9% in 2004; p < 0.003). Higher income was associated with younger age at diagnosis of CRC (odds ratio [OR] for quartile 1 vs quartile 4: 0.54; 95% CI: 0.47–0.62). Other factors associated with younger age at diagnosis included female sex (OR for male vs female: 0.85; 95% CI: 0.78–0.94), distal CRC (OR: 1.66; 95% CI: 1.50–1.84) and North zone (OR for South zone vs North zone: 0.74; 95% CI: 0.60–0.92). Conclusion: The proportion of patients (out of the overall CRC population) with early-onset CRC, increased in Alberta throughout the study duration (particularly left-sided CRC). There is a need to reassess the current age limits for CRC screening in Canada in view of these findings.
Lay abstract
In this study, we found that the percentage of younger individuals with colorectal cancer has increased in Alberta, particularly for cancers arising from the rectum and left side of the colon. Reassessment of the recommended age to start colorectal cancer screening in Canada is needed.
Supplementary data
To view the supplementary data that accompany this paper please visit the journal website at: www.tandfonline.com/doi/suppl/10.2217/fon-2021-0592
Acknowledgments
This work was completed thanks to the efforts of the analytical teams at surveillance and reporting, CancerCare Alberta in terms of data extraction from provincial resources.
Financial & competing interests disclosure
O Abdel-Rahman is on the advisory board for Eisai, Lilly, Ipsen and Roche. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.
No writing assistance was utilized in the production of this manuscript.
Ethical conduct of research
This work was approved by Health Research Ethics Board of Alberta (HREBA.CC-20-0215) and conducted according to the principles outlined in the Declaration of Helsinki. Given the retrospective nature of the data collection, informed consent was waived by the ethics committee.