Adjuvant chemotherapy for stage III colorectal cancer in the elderly

Background

Colorectal cancer (CRC) is a common and lethal malignancy which is related to aging, with almost 40% of CRC diagnosed above 75 years in both Australia and the United States. Adjuvant chemotherapy is a key treatment in patients with Stage III colorectal cancer, and combination chemotherapy using a fluoropyrimidine and oxaliplatin doublet (such as FOLFOX or XELOX) is the current standard of care, with a 20% reduction in risk of death compared to fluoropyrimidine monotherapy. It is not clear if this benefit is seen in elderly patients in the community setting.

Methods

TNM stage, chemotherapy treatment records, and overall survival data was obtained for 2923 patients with stage III colorectal cancer by linkage of New South Wales cancer registry records with data from the births, deaths and marriages registry. To determine the impact of age, two separate cox proportional hazard models were used to compare the effect of combination chemotherapy regimens on overall survival (OS) for patients 70 and older, and younger than 70. Multivariate analysis was performed using a subset of 1008 patients with more complete clinicopathologic data.

Results

Patients in the 70yrs and older age group had poorer OS (5yr OS 58.8 vs 76.7%, HR 0.47 95%CI 0.41 – 0.54, p

Conclusions

Patients 70 years and older, with stage III colorectal, may gain a similar OS benefit with adjuvant oxaliplatin doublet chemotherapy as younger patients. Combination adjuvant chemotherapy should be considered in elderly patients

Clinical trial identification

Legal entity responsible for the study

The Centre for Oncology Education and Research Translation (CONCERT)

Funding

The Centre for Oncology Education and Research Translation (CONCERT)

Disclosure

All authors have declared no conflicts of interest.