Impact of PET staging in limited-stage SCLC.

Abstract

7098 Background: Although PET/CT has been established for the initial staging of NSCLC, it is still unproven for SCLC. This study examines clinical outcome in patients with limited-stage SCLC staged with and without PET/CT. Methods: An institutional database was reviewed to identify all patients that presented with limited-stage SCLC and treated definitively with concurrent chemoradiation. Overall survival and associations were assessed by the Kaplan-Meier approach, log-rank tests and Cox modeling. Results: From 01/04 – 08/10, 54 consecutive limited-stage SCLC patients were treated with concurrent chemoradiation at the University of Pennsylvania. 40 patients underwent PET staging; 14 underwent CT staging only; all had MR of the brain. Patient characteristics were well distributed, including age (p = 0.35), race (p = 0.21), sex (p = 0.93), dose (45 Gy, p = 0.89), and fractions per day (p = 0.89). PET-staged patients had median survival of 32 vs 15 months in patients without PET (p = 0.03). Survival rate was 57% vs 29% at 24 months. Median time to distant failure of 29 vs 11 months (p = 0.05). Median time to local failure was 41 vs 12 months (p = 0.03). Median followup was 38 months in the 19 surviving PET-staged patients and 40 in the 2 surviving non-PET patients (p = 0.59). Lack of PET-staging (OR = 0.92, p = 0.04) and race (OR = 1.02, p = 0.03) associated with increased distant failure on multivariate Cox analysis. Only PET-staging (OR = 0.93, p = 0.04) associated with increased overall survival on univariable Cox modeling. Conclusions: Median and overall survival of PET-staged SCLC patients compared favorably with those who were not. These findings are presumably due primarily to identification of CT-occult distant disease by PET. This study underscores the value of PET in staging patients with SCLC.