BACKGROUND: Febrile neutropenia (FN) is a serious and potentially life-threatening condition that may develop in patients with cancer who receive myelosuppressive chemotherapy. The risk of mortality from FN is not well characterized in current clinical practice. METHODS: Patients with cancer who were receiving chemotherapy in clinical practice were identified from a large US healthcare claims database, and mortality was confirmed using the National Death Index. Patients with FN had their propensity scores matched within tumor types of interest (non-Hodgkin lymphoma and breast, lung, colorectal, and ovarian cancers) to patients who did not experience FN. Study endpoints of overall mortality (anytime during follow-up), early mortality (during the first 12 months of the first chemotherapy course), and hospitalization were examined using univariate and multivariate techniques. RESULTS: Matched FN and control groups each included 5990 patients, and the average follow-up for both groups was 17.6 months. Crude incidence rates of early mortality were significantly higher for patients with FN compared with controls for all tumor types. Proportional hazards regression demonstrated a significant increase in the risk of overall and early mortality in patients with FN compared with controls (hazard ratio [HR], 1.15 [95% confidence interval, 1.02-1.29] and HR, 1.35 [95% confidence interval, 1.09-1.67], respectively). CONCLUSIONS: The adjusted risk of mortality in patients who experienced FN was at least 15% higher than in comparably matched patients without FN, supporting the inference that infectious complications because of neutropenia resulting from myelosuppressive chemotherapy are clinically important.