Although the elderly account for the majority of patients with cancer and receive most of the chemotherapy administered, the relative efficacy and toxicity of chemotherapy in those over the age of 65 years is still a controversial and under-researched area. Age-related physiological changes may lead to the reduced tolerability of anticancer treatments and risk factors that may increase the likelihood of adverse events. However, treatment policies chosen to reduce toxicity may compromise therapeutic results, creating the impression that chemotherapy may be less effective in the elderly. The older cancer patient will frequently have concomitant chronic diseases which may affect the choice or dose of chemotherapy. Close attention should also be paid to potential interactions of medications with chemotherapy.

Adjuvant fluorouracil based chemotherapy for colorectal cancer (CRC) in the elderly have shown comparable toxicity rates compared with younger patients.1 Oxaliplatin based adjuvant chemotherapy in the elderly has shown benefit,2 although data suggests the benefits in patients older than 70 may be reduced3, and should be considered on an individual basis. A higher incidence of adverse events compared to fluorouracil have also been reported.4

In metastatic CRC, older adults are at risk of increased haematological toxicities from chemotherapy.5 A stop and go approach may be desirable to minimise toxicity.6 Anti-EGFR based therapies have acceptable toxicity profiles in the elderly,7 while anti-angiogenic therapies may have a higher rate of toxicity.8

Any therapeutic decision regarding any patient should be based on physiological rather than chronological age. An individualised approach to dosing of chemotherapy is required in elderly patients.