High tumor metabolic activity as measured by fluorodeoxyglucose positron emission tomography is associated with poor prognosis in limited and extensive stage small-cell lung cancer.

Abstract

PURPOSE: We investigated the prognostic effect of incorporating metabolic assessment by (18)F-fluoro-2-deoxyglucose uptake on positron emission tomography/computed tomography ((18)F-FDG-PET/CT) into a conventional staging system in small-cell lung cancer (SCLC).

EXPERIMENTAL DESIGN: Seventy-six consecutive patients with pathologically proven SCLC were enrolled. All patients underwent standard treatment after pretreatment (18)F-FDG-PET/CT scanning. The mean values of maximal standardized uptake values (meanSUV(max)) of the malignant lesions upon (18)F-FDG-PET/CT were calculated. The Cox proportional hazards model was used with performance status, lactate dehydrogenase, stage, and meanSUV(max).

RESULTS: Patients with high meanSUV(max) were significantly related with the established poor prognostic factors, such as higher lactate dehydrogenase (P = 0.04) and extensive disease (ED; P = 0.01). Furthermore, in multivariate analysis, patients with high meanSUV(max) were associated with poor survival outcomes compared with patients with low meanSUV(max) [adjusted hazard ratio, 3.74; 95% confidence interval (95% CI), 1.67-8.37; P = 0.001, for death and adjusted hazard ratio, 2.25; 95% CI, 1.21-4.17; P = 0.01 for recurrence/progression]. In subgroup analysis, limited disease (LD) with high meanSUV(max) showed significantly shorter overall survival than LD with low meanSUV(max) [high versus low meanSUV(max), 20.1 months (95% CI, 7.9-23.2) versus 35.3 months (95% CI, 27.6-42.9); P = 0.02]. ED with high meanSUV(max) had significantly shorter overall survival than ED with low meanSUV(max) [high versus low meanSUV(max), 9.5 months (95% CI, 4.9-13.9) versus 17.7 months (95% CI, 12.0-20.1); P = 0.007]. These findings were replicated in progression-free survival analysis.

CONCLUSIONS: In SCLC, tumor metabolic activity as assessed by FDG-PET is a significant prognostic factor and identifies subgroups of patients at higher risk of death in both LD and ED SCLC.