Prognostic Value Of Pet/Ct Volumetric Prognostic Index In Operable Nsclc Patients.

8548 Background: We developed a PET/CT volumetric prognostic staging system (PVP index) using risk-based models integrating hazard of death from both whole-body metabolic tumor volume (MTVWB ) and TNM stage, and showed its greater prognostic power than TNM stage in NSCLC of different stages and treatments. This study is designed to further confirm its prognostic value in operable NSCLC patients. Methods: We performed an IRB-approved retrospective review of 377 operable patients with a new NSCLC diagnosis from 2004 to 2015. Clinical TNM stage, initial PET MTVWB , and long-term survival data were collected. 27 patients refused surgery, 350 patients had surgical treatment (187 surgery alone, 82 surgery+chemotherapy, 11 surgery+radiation, 70 surgery+chemoradiation). Ten of 350 surgically treated patients who died within 1 month after surgery were excluded. 367 patients were included in the analysis, with a median age of 68.7 years, 58% women, and mean follow-up among survivors of 4.43 years. TNM stage was IA (37.3%), IB (16.9%), IIA (11.2%), IIB (4.1%), IIIA (15.0%), IIIB (5.5%) and IV (10.1%). Cox regression analyses were performed to derive Gonen and Heller's Concordance Index (GHCI) to evaluate the discriminatory power and prognostic accuracy of the PVP index and TNM stage, respectively. Bootstrapping was conducted to test the statistical difference between the GHCIs. Results: A lower PVP index was significantly associated with better overall survival (univariate Cox regression P< 0.001 and multivariate P< 0.001, respectively).Univariate analysis showed that PVP index (GHCI = 0.6238, P< 0.01) has greater discriminatory power than TNM stage (GHCI = 0.6155). Multivariate analyses showed that the model with PVP index has greater overall discriminatory power (GHCI = 0.6983, p < 0.01) than TNM stage (GHCI = 0.6839) with other identical co-variables. The adjusted hazard ratio for the PVP index was 2.03 (95% CI = 1.52 to 2.73, p < 0.001), after controlling for age, gender, performance status, treatment received and tumor histology. Conclusions: The PVP index shows equivalent performance and may contain richer information about operable NSCLC patient prognosis than the current TNM staging system, and hence deserves further investigation.