Revisiting a longstanding clinical trial exclusion criterion: impact of prior cancer in early-stage lung cancer

BACKGROUND: Early-stage lung cancer represents a key focus of numerous multicenter clinical trials, but common exclusion criteria such as a prior cancer diagnosis may limit enrollment. We examined the prevalence and prognostic impact of a prior cancer diagnosis among patients with early-stage lung cancer. METHODS: We identified patients>65 years of age with early-stage lung cancer diagnosed 1996–2009 in the Surveillance, Epidemiology, and End Results-Medicare linked database. Prior cancers were characterized by type, stage, and timing with respect to the lung cancer diagnosis. All-cause and lung cancer specific-survival rates were compared between patients with and without prior cancer using Cox regression analyses and propensity scores. RESULTS: Among 42,910 patients with early-stage lung cancer, one-fifth (21%) had a prior cancer. The most common prior cancers were prostate (21%), breast (18%), gastrointestinal (17%), and other genitourinary (15%). Most prior cancers were localized, and 61% were diagnosed within 5 years of the lung cancer diagnosis. There was no difference in all-cause survival between patients with and without prior cancer (hazard ratio [HR] 1.01; P=0.52). Lung cancer specific survival was improved among patients with prior cancer (HR 0.79; P<0.001). CONCLUSIONS: A prior cancer history may exclude a substantial proportion of patients with early-stage lung cancer from enrollment in clinical trials. Without adverse effect on clinical outcomes, inclusion of patients age >65 years with prior cancer in clinical trials should be considered to improve study accrual, completion rates, and generalizability.