Prognostic significance of metabolic parameters measured by (18)F-fluorodeoxyglucose positron emission tomography/computed tomography in patients with small cell lung cancer.

OBJECTIVE: The aim of this study was to evaluate the prognostic significance of some metabolic parameters measured by (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) in patients with small cell lung cancer (SCLC).

METHODS: We retrospectively reviewed 98 patients with pathologically proven SCLC who underwent pre-treatment (18)F-FDG PET/CT. Metabolic tumor volume (MTV), integrated standardized uptake value (iSUV) and average SUV (SUV(mean)) of all malignant lesions, and maximum SUV (SUV(max)) of the primary tumor were measured by (18)F-FDG PET/CT. We determined the relationship between overall survival (OS) and progression free survival (PFS) and these PET metabolic parameters.

RESULTS: The estimated median OS and PFS for the entire cohort were 16.7 months and 9.8 months. The patients with larger MTV had significantly shorter median OS (9.6 months vs 23.2 months, P<0.001) and PFS (6.9 months vs 15.5 months, P<0.001) than the patients with smaller MTV. On multivariate analysis, MTV, iSUV, tumor stage and LDH were the significantly prognostic factors with OS and PFS. SUV(max) did not show correlation with OS and PFS. In subgroup analysis, limited disease (LD) with larger MTV showed significantly shorter median OS and PFS than LD with smaller MTV. Extensive disease (ED) with larger MTV also had significantly shorter median OS and PFS than the same stage with smaller MTV.

CONCLUSIONS: MTV and iSUV are important independent prognostic factors for survival in patients with SCLC. Either MTV or iSUV may identify subgroups of patients at higher risk of progression or death in both LD and ED SCLC.