There are fewer reports on the clinical course of untreated early-stage NSCLC than for other NSCLC populations and significant ethical difficulty in randomizing between treatment and no treatment even among those at high risk, but there is sufficient evidence to define the survival in this group as dismal. In addition to the cited work, three institutional series2-4 and a population-based review from the California Cancer Registry5 report on the natural history of untreated early-stage NSCLC. Although retrospective reviews are imperfect, and the subject difficult because of the multifaceted reasons for which patients forgo treatment, three salient points are clearly conveyed across all the series: (1) comorbid pulmonary disease is the primary reason for nontreatment, (2) 5-year overall survival in the untreated is <10%, and (3) at least one-half of the deaths are attributed to NSCLC. The California Cancer Registry review identified adenocarcinoma in situ as a common histology among the small number of untreated survivors at 5 years, outlining an indolent tumor type that may have an altered risk-benefit ratio related to treatment. The high-risk population is diverse, and for some, but not all, competing comorbidity is a valid reason to abstain from treatment, especially if not amenable to less invasive modalities.