Adjuvant treatment in older patients with rectal cancer: a population-based review

Little is known about the benefits of adjuvant chemotherapy (adj) in the older population with locally advanced rectal cancer (larc). We evaluated use of adj, survival outcomes, and adj-related toxicity in older patients with larc.

Our retrospective review included 286 patients with larc (stages ii and iii) diagnosed between January 2010 and December 2013 in Nova Scotia who underwent curative-intent surgery. Baseline patient, tumour, and treatment characteristics were collected. The survival analysis used the Kaplan-Meier method and Cox regression statistics.

Of 286 identified patients, 152 were 65 years of age or older, and 92 were 70 years of age or older. Median follow-up was 46 months, and 163 patients (57%) received neoadjuvant chemoradiation. Although adj was given to 81% of patients (n = 109) less than 65 years of age, only 29% patients (n = 27) 70 years of age and older received adj. Kaplan-Meier analysis suggested a potential survival advantage for adj regardless of age. In multivariate Cox regression analysis, Eastern Cooperative Oncology Group performance status, T stage, and adj were significant predictors of overall survival (p < 0.04); age was not. Similarly, N stage, neoadjuvant chemoradiation, and adj were significant predictors of disease-free survival (p < 0.01). Poor Eastern Cooperative Oncology Group performance status was the most common cause of adj omission. In patients 70 years of age and older, grade 1 or greater chemotherapy-related toxicities were experienced significantly more often by those treated with adj (85% vs. 68% for those not treated with adj, p < 0.05).

Regardless of age, patients with larc seem to experience a survival benefit with adj. However, older patients are less likely to receive adj, and when they do, they experience more chemotherapy-related toxicities.