Objective: We sought to assess whether the standard uptake value of a pulmonary nodule is an independent predictor of biologic aggressiveness. Methods: This is a retrospective review of a prospective database of patients with non-small cell lung cancer. Patients had dedicated positron emission tomography scanning with F-18 fluorodeoxyglucose, with the maximum standard uptake value measured. All suspicious nodal and systemic locations on computed tomographic and positron emission tomographic scanning underwent biopsy, and when indicated, resection with complete lymphadenectomy was performed. Results: There were 315 patients. Multivariate analysis showed patients with a high maximum standard uptake value (≥10) were more likely to have poorly differentiated tumors (risk ratio, 1.5; P = .005) and advanced stage (risk ratio, 1.9; P = .010) and were less likely to have their disease completely resected (risk ratio, 3.7; P = .004). Maximum standard uptake value was the best predictor of disease-free survival (hazard ratio, 2.5; P = .039) and survival (hazard ratio, 2.8; P = .001). Stage-specific analysis showed that patients with stage IB and stage II disease with a maximum standard uptake value of greater than the median for their respective stages had a lower disease-free survival at 4 years (P = .005 and .044). The actual 4-year survival for patients with stage Ib non-small cell lung cancer was 80% versus 66% (P = .048), for stage II disease it was 64% versus 32% (P = .028), and for stage IIIa disease it was 64% versus 16% (P = .012) for the low and high maximum standard uptake value groups, respectively. Conclusions: The maximum standard uptake value of a non-small cell lung cancer nodule on dedicated positron emission tomography is an independent predictor of stage and tumor characteristics. It is a more powerful independent predictor than the TNM stage for recurrence and survival for patients with early-stage resected cancer. This information might help guide treatment strategies. Copyright © 2005 by The American Association for Thoracic Surgery.