Rationale: Insurance coverage is an important determinant of access to care and is one potential cause of disparities in lung cancer care outcomes.

Objectives: We performed a systematic review of the available literature to examine the association between insurance status and lung cancer practices and outcomes.

Methods: We searched multiple electronic databases through November 6, 2008 for studies that examined the association between lung cancer outcomes and insurance status. Two reviewers independently selected studies. One investigator evaluated their quality according to predetermined criteria, and abstracted data about study design, patients' demographic and clinical characteristics, and outcome measures.

Measurements and main results: Of 3,798 potentially relevant studies, 23 met eligibility criteria and were included. Studies reported heterogeneous outcomes among heterogeneous samples of patients that precluded a quantitative synthesis. In general, compared with patients with private or Medicare insurance, patients with Medicaid or no insurance had poorer lung cancer outcomes, including higher incidence rates, later stage at diagnosis, and poorer survival. Overall, patients with Medicaid or no insurance were less likely to undergo curative procedures, but patients without insurance were more likely to receive guideline-concordant care.

Conclusions: Patients with Medicaid or no insurance consistently had worse outcomes than other patients with lung cancer. Some of the disparities may be secondary to residual confounding from smoking and other health behaviors, but available data suggest that patients with lung cancer without insurance do poorly because access to care is limited and/or they present with more advanced disease that is less amenable to treatment.