Purpose: Oncological strategies in the elderly population are debated. The objective of this study was to assess the factors predictive of poor prognosis in elderly patients with stage III colon cancer.
Methods: A retrospective review of demographic, pathologic, treatment, and outcome data from 308 patients with stage III colon adenocarcinoma who had undergone surgery between 2007 and 2014 was conducted. A proportional hazards model was used to assess the association of prognostic factors with disease-free survival (DFS) and overall survival (OS).
Results: The 5-year survival rate was 34.4% (95% CI 27.1-39.8%) and Charlson comorbidity index was a significant predictor of death (p < 0.01). The presence of perineural invasion (p = 0.03) and incomplete resection (p < 0.001) were significantly correlated with OS. The postoperative (30 days) mortality rate was 11.7%. Adjuvant chemotherapy was significantly associated with better OS (p < 0.001) independently of the regimens. Disease-free survival was significantly correlated with adjuvant chemotherapy (HR 0.63, 95% CI: 0.42-0.97, p = 0.034), Charlson comorbidity index (CCI 5; HR 1.61, 95% CI: 1.05-2.48, p = 0.029), and venous and/or perineural invasion (HR 1.54, 95% CI: 1.03-2.29, p = 0.035).
Conclusion: Age, comorbidities, tumor histology, and adjuvant chemotherapy were independent predictors of prognosis in patients with stage III colon cancer. These data can be used to identify elderly patients with poor prognosis and to design future tailored randomized clinical trials.
Trial registration: ClinicalTrial.gov No. NCT04526314. Date of registration 25 August 2020.
Keywords: Chemotherapy; Elderly; Stage III colon cancer; Surgery; Survival.