Results in the elderly with locally advanced rectal cancer from the ACCOR12/PRODIGE 2 phase III trial: tolerance and efficacy

Abstract

Background: Rectal cancer predominantly affects the elderly. Unfortunately, this age category is under-represented in clinical trials because clinicians are loath to include patients with a high risk of comorbidity.

Patients and methods: An exploratory analysis of the ACCORD12/PRODIGE 2 phase III trial was carried out to retrospectively compare the benefit of neoadjuvant chemotherapy between the elderly (≥70 years; n=142) and younger patients (<70 years; n=442), this analysis was not preplanned in the study protocol. Patients with histologically confirmed resectable stage T3 or T4 rectal adenocarcinoma were eligible with an age limit of 80 years.

Results: Overall, the two age categories did not statistically differ in terms of patient's clinical and tumor baseline characteristics. Preoperative chemoradiotherapy leads to more severe grade 3/4 toxicities (25.6% vs. 15.8%, p=0.01) and more permanent stomas (33.3% vs. 22.8%, p=0.014) in elderly patients who were less often operated on than younger patients (95.8% vs. 99.0%, p=0.008). The relative number of interventions per surgery type (p=0.18), treatment efficacy in terms of R0 resection rate (88.6% vs. 90.6%; p=0.54) and complete pathological response (14.7% vs. 16.9%; p=0.55) were nearly identical between the two categories.

Conclusion: Altogether these results warrant the development of specific optimal therapeutic strategies for the elderly.

Keywords: Capecitabine; Elderly; Exploratory analysis; Neoadjuvant chemoradiotherapy; Oxaliplatin; Rectal cancer.