Prognostic value of pre-operative glucose-corrected maximum standardized uptake value in patients with non-small cell lung cancer after complete surgical resection and 5-year follow-up

Abstract

Introduction: In this study we evaluated the value of pre-operative glucose corrected maximum standard uptake value (GC-SUVmax) as prognostic factor in patients with early stage non-small cell lung cancer (NSCLC) after complete surgical resection.

Methods: This study was designed as a retrospectively evaluated single center study with prospective data registry. Inclusion criteria were: histologically proven stage I NSCLC, 18F-FDG-PET/CT scan prior to surgery, complete resection (R0) and follow up in our outpatient department. Exclusion criteria were: history of malignancy other than NSCLC, diabetes and (neo) adjuvant therapy. Follow up period was 5 years.

Results: Between 2006 and 2008 a total of 33 patients (16 males, 17 females) met the inclusion criteria. SUVmax and GC-SUVmax were strongly correlated (Spearman's ρ = 0.97). Five-year overall survival (OS) rate was 70 % (95 % CI = 56-87 %). Patients who died within 5 years of follow up had significantly higher pre-operative GC-SUVmax (median = 10.6, IQR = 8.3-14.4) than patients who were alive at 5-year follow up (median = 6.4, IQR = 3.0-9.8), p = 0.04. SUVmax showed similar differences: 10.4 (8-12.9) vs. 6.6 (3.0-8.8), p = 0.047. The area under the receiver-operating characteristic (ROC) curve at 5 years was 0.70 (95 % CI = 0.50-0.90) for GC-SUVmax and 0.71 (95 % CI = 0.51-0.91) for SUVmax (p = 0.75).

Conclusion: Pre-operative FDG tumor uptake in patients with NSCLC is predictive for survival after complete surgical resection. GC-SUVmax, as an additional value to SUVmax, may better approach competitive inhibition of FDG and glucose in tumors, however, in this study this potential advantage, if any, was very small.

Keywords: Early stage; Non-small cell lung cancer; PET/CT; Prognostic; Surgery.