Background: Rectal cancer predominantly occurs in older adults given the average age of diagnosis of 63 years. We aimed to compare the patterns of care and outcomes of older adults and younger adults who had resection for stage I-IV primary rectal cancer at Concord Repatriation General Hospital.
Methods: Patients who had resection of stage I to IV rectal cancer between 1995-2010 were identified from a prospective database and stratified into two age groups: <70 years and ≥70 years. Age-associated differences in patients, cancer, and treatment characteristics were determined by Chi-square tests. 5-year cancer specific survival (CSS) and overall survival (OS) were determined by Kaplan- Mayer method followed by multivariable cox regression analysis to adjust for potential confounding factors.
Results: Of 714 included patients, the mean age was 65.8 years (range, 21-92 years) and two thirds were male (271, 66.6%). 407 (57%) patients were aged <70y and 307 (43%) were aged ≥70 years. Older age (>70years) predicted more comorbidity (p < 0.001), heart problems (p < 0.001), earlier stage cancer (p = 0.01). In stage III, older adults compared with younger received less neoadjuvant chemotherapy [7/32 (21.9%) p = 0.058], less neoadjuvant radiotherapy [8/50 (16.0%) p = 0.001] and less adjuvant chemotherapy [30/147 (20.4%) p < 0.001]. Older age was associated with worse OS and CSS by stage (p < 0.001 and p = 0.001 respectively). In stage III, adjuvant chemotherapy independently predicted improved OS (p < 0.001).
Conclusion: Older adults with rectal cancer received less neoadjuvant and adjuvant therapy and had worse OS and CSS than their younger counterparts. Ways to increase neoadjuvant and adjuvant treatment utilisation in older adults with rectal cancer are needed.