Impact of PET Staging in Limited-Stage Small-Cell Lung Cancer

Introduction: Although positron emission tomography computed tomography (PET-CT) has been widely used for small-cell lung cancer (SCLC) staging, no study has examined the clinical impact of PET staging in limited-stage (LS) SCLC. Methods: We identified patients with LS-SCLC treated definitively with concurrent chemoradiation. Outcomes were assessed using the Kaplan-Meier approach, Cox regression, and competing risks method. Results: We treated 54 consecutive LS-SCLC patients with concurrent chemoradiation from January 2002 to August 2010. Forty underwent PET, 14 did not, and all underwent thoracoabdominopelvic CT and magnetic resonance imaging neuroimaging. Most patient characteristics were balanced between the comparison groups, including age, race, sex, bone scanning, median dosage, and performance status. More number of PET-staged patients presented with nodal metastases (p = 0.05). Median follow-up was similar for PET-staged and non-PET-staged patients (p = 0.59). Median overall survival from diagnosis in PET-staged patients was 32 versus 17 months in patients staged without PET (p = 0.03), and 3-year survival was 47% versus 19%. Median time-to-distant failure was 29 versus 12 months (p = 0.04); median time-to-local failure was not reached versus 16 months (p = 0.04). On multivariable analysis, PET staging (odds ratio [OR] = 0.24; p = 0.04), performance status (OR = 1.89; p = 0.05), and N-stage (OR = 4.94; p < 0.01) were associated with survival. Conclusion: LS-SCLC patients staged with PET exhibited improved disease control and survival when compared with non-PET-staged LS-SCLC patients. Improved staging accuracy and better identification of intrathoracic disease may explain these findings, underscoring the value of PET-CT in these patients.