Positron emission tomography for predicting recurrence in stage I lung adenocarcinoma: standardized uptake value corrected by mean liver standardized uptake value

Abstract

F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) has become an important staging tool for patients with lung cancer, and determination of the standardized uptake value (SUV) is probably the most widely used method for evaluating patients. Although SUV is recognized as a powerful surrogate marker for lung cancer outcomes, SUV standardization and reproducibility in clinical practice remain major concerns. The aim of this study was to evaluate the corrected SUV as a universal marker for lung cancer recurrence. We conducted a case-control study in our institute. From May 2004 to February 2010, 141 patients with pathological stage IA and IB adenocarcinomas underwent PET-computed tomography scanning and SUV determination. The corrected SUV was defined as the SUV index, which was calculated as the ratio of tumor SUV(max) to liver SUV(mean). We examined the association between disease-free survival and several clinicopathological factors, including the SUV index. The 3-year overall survival rate after surgery was 94.3% and the 3-year disease-free survival rate was 90.4%. Univariate analysis showed that male gender (p=0.04), smoking (p=0.02), and SUV index (p<0.01) were independent predictive factors for recurrence. Multivariate analysis showed that the SUV index was significantly associated with a high risk for recurrence (p=0.03). No patient with an SUV index <1.0 experienced a recurrence. The SUV index is a significantly predictive and reproducible factor for recurrence in pathological stage I lung cancers. Patients with an SUV index <1.0 were more likely to have a good prognosis. Additional multi-institutional studies are needed to confirm these study results.