Background: The aim of the current study was to determine whether the [18F]-2-fluoro-deoxy-D-glucose (FDG) positron emission tomography (PET) standardized uptake value (SUV) in patients with a new diagnosis of stage I lung cancer correlates with a specific cellular component in the primary tumor.
Methods: This study was Health Insurance Portability and Accountability Act compliant and approved by our Institutional Review Board with a waiver of informed consent. Forty patients with stage I nonsmall cell lung cancer (NSCLC) who underwent FDG-PET imaging at the time of diagnosis followed by surgical resection were retrospectively identified. Histologic sections of the primary tumor were reviewed by a pathologist without any clinical data and scored according to the percentage of each cellular component (tumor cells, normal stroma, inflammatory cells, necrosis, fibrosis, and other). Each component was compared with maximal (SUV(max)) and mean (SUV(mean)) SUVs using Pearson correlation coefficient analysis.
Results: The mean SUV(max) and SUV(mean) values for 40 stage I NSCLC tumors were 8.8 and 5.4, respectively. The mean histologic composition of tumor specimens in order of frequency was as follows: tumor cells (38.9%), fibrosis (30.8%), inflammatory cells (14.8%), normal stroma (5.2%), necrosis (5.8%), and other components (4.5%); however, there was considerable variation noted among individual tumors. There was no statistically significant correlation between SUV(max) (r = .19; P = .24) or SUV(mean) (r = .017; P = .29) and the proportion of tumor cells in the tumor mass or any other cellular components.
Conclusions: The cellular composition of stage I NSCLC appears to be highly variable, with no correlation noted between a specific tumor cellular component and FDG activity.
Cancer 2010. (c) 2010 American Cancer Society.