Positron-emission tomography as a prognostic tool for early-stage lung cancer

Background Positron-emission tomography (PET) shows tissue metabolic activity in the form of the standard uptake value (SUV). This study examines the prognostic value of the SUV for early-stage lung cancer. Methods A retrospective review of 187 patients undergoing PET for potential lung cancer. Data collected included patient demographics, tumor pathology, and survival information. Data were correlated with PET results to determine if a prognostic relationship exists. Results The sensitivity and specificity of PET for detecting malignant lesions were 98% and 24%. Malignant lesions had a higher SUV than benign lesions (5.9 ± 6.2 versus 2.2 ± 1.8, P < .0001). The average SUV of well-differentiated tumors was 2.6 ± 3.1 versus 5.9 ± 5.5 for other tumors (P = .010). There was a strong correlation between tumor stage and SUV (analysis of variance, P < .0001). There was no difference in tumor SUV for survivors versus nonsurvivors. Conclusions The SUV correlates with prognostic indicators, such as tumor stage and grade. The SUV alone was not an independent predictor of survival.