Reasons for Underuse of Adjuvant Chemotherapy in Elderly Patients with Stage III Colon Cancer

Objectives: Our aims were to characterize adjuvant chemotherapy (AC) use among elderly patients (EPs) with stage III colon cancer (CC) and to identify potential reasons for under-treatment. Methods: Descriptive statistics... [ view full abstract ]

Objectives: Our aims were to characterize adjuvant chemotherapy (AC) use among elderly patients (EPs) with stage III colon cancer (CC) and to identify potential reasons for under-treatment.
Methods: Descriptive statistics were used to summarize treatment patterns in young patients (YPs) aged <70 vs. EPs ≥70 years. Multivariate Cox regression models were constructed to evaluate the associations between AC and cancer-specific (CSS), disease-free (DFS), and overall survival (OS) and to determine whether these were modified by age.
Results: We identified 810 patients: 51% men, 52% YPs, and 74% received AC. Compared to YPs, EPs were less likely to receive AC (57% vs. 91%, p<0.01). Frequent reasons for non-treatment included age, comorbidities and perceived minimal benefit from AC. Among AC-treated individuals, EPs were less likely to receive FOLFOX (32% vs. 74%, p<0.01) because of advanced age, comorbidities, and patient preference. Once AC was given, EPs had similar rates of treatment discontinuations (34% vs. 26%, p>0.05) and dose reductions (63% vs. 61%, p>0.05) as YPs. Reasons for treatment interruptions included side effects, progressive disease, and patient choice. Receipt of either FOLFOX or capecitabine was correlated with improved CSS, DFS and OS when compared to surgery alone; this effect was not modified by age.
Conclusions: EPs with stage III CC frequently received either no AC or capecitabine monotherapy due to advanced age and comorbidities. The effect of AC on survival was similar across age groups, with comparable side effects and rates of treatment modifications. AC should not be withheld because of advanced age alone.