Managing choices for older patients with colon cancer: adjuvant therapy

Colon cancer is among the most common cancers in the United States, and the median age of patients at diagnosis is 70. Medical oncologists are commonly asked to comprehensively evaluate elderly patients to estimate individual risk/benefit ratios for adjuvant treatment. Although 40% of patients with colon cancer are elderly, clinical trials enroll mainly younger patients. Consequently, we are forced to depend on subgroup analyses, observational studies, and personal experience to guide recommendations. Decision-making in adjuvant therapy for colon cancer is increasingly complex, as we subdivide patients with stage II to III colon cancer by molecular as well as anatomic staging to predict which are likely to benefit from chemotherapy and then whether the addition of oxaliplatin to 5-fluorouracil (5-FU) is worth the toxicity. It is likely that the tumor biology of younger and older patients differs, and more research is needed to dissect out the biologic heterogeneity of both the tumors and their elderly hosts to help guide treatment. We recognize that our evaluations should not solely be based on temporal age and factor physiology, pharmacology, psychology, functional status, and social support into these considerations. Older patients who are treated must be monitored closely for toxicities when undergoing treatment. Although there is a clear need for clinical trials in this population, treatment decisions confront us today in the absence of definitive evidence. How can we help our patients navigate through these important choices?