Prognostic value of positron emission tomography for non-small cell lung cancer survival; analysis of 268 cases

Abstract

7227 Background: Positron emission tomography (PET) is more accurate than computed tomography (CT) in the staging of non-small cell lung cancer (NSCLC). We analyzed the prognostic value of PET for survival in NSCLC patients. Methods: Consecutive patients with proven NSCLC who had PET for staging were selected. All patients had been evaluated by laboratory tests, bronchoscopy, chest X-ray, and CT of the chest and upper abdomen. A clinical stage (c-TNM) was determined prior to PET. A pet-TNM was obtained by observers blinded to clinical data. We used the McNemar test to compare c-TNM and pet-TNM. Univariate survival analyses were performed with the Kaplan-Meier method and log rank test, for performance score, sex, weight loss, comorbidity, histology, hilar and paramediastinal tumor location, c-TNM, and pet-TNM. Cox regression analysis was performed with the significant variables of the univariate analyses, together with age and interaction variables. Results: From 1996 until 2001, 268 patients were included, 206 men and 62 women. Median age was 63 years (range, 29–88), ECOG performance score was 0/1/2 in 114/135/19 patients, 37% had squamous and 30% had adenocarcinoma. c-TNM and pet-TNM were identical in 150 (56%) patients, 68 were upstaged and 48 were downstaged by PET, and 2 without c-TNM had stage IB/IV. c-TNM did not overlap with pet-TNM (p = 0.024). At analysis, 212 (79%) patients had died. Median survival in months was not reached for stage IA (pet-TNM), 45 for stage IB, 21 for IIA, 29 for IIB, 13 for IIIA, 14 for IIIB, and 9 for stage IV. At univariate analysis, survival difference between the arms was significant for performance score (0 vs. 1/2), weight loss (< 10% vs. ≥ 10%), pulmonary comorbidity and paramediastinal location (no vs. yes), c-TNM and pet-TNM (stage I vs. II vs. IIIA vs. IIIB vs. IV). At Cox regression analysis, pet-TNM was the only significant (p < 0.001) predictor of poor survival, while c-TNM, performance score, and weight loss were not significant. Conclusion: Tumor stage as determined by PET is the best prognostic factor for survival in patients with NSCLC. No significant financial relationships to disclose.