Multifunctional Profiling of Non Small Cell Lung Cancer Using 18F-FDG PET/CT and Volume Perfusion CT

The aim of this study was to investigate correlations between glucose metabolism registered by F-18-FDG PET/CT and tumor perfusion quantified by volume perfusion CT and immunohistochemical markers Ki67 and microvessel density (MVD) in patients with non-small cell lung cancer (NSCLC). Methods: Between February 2010 and April 2011, 24 consecutive patients (21 women, 3 men; mean age +/- SD, 67.6 +/- 6.8 y; age range, 55.6-81.3 y) with histologically proven NSCLC (14 adenocarcinoma, 9 squamous cell lung carcinoma [SCC], and 1 mixed adenocarcinoma and SCC) underwent F-18-FDG PET/CT and additional volume perfusion CT. Maximum standardized uptake value (SUVmax), mean SUV, and the metabolic tumor volume were used for F-18-FDG uptake quantification. Blood flow (BF), blood volume (BV), flow extraction product (K-trans), and standardized perfusion value (SPV) were determined as CT perfusion parameters. Both perfusion parameters and F-18-FDG uptake values were subsequently related to the histologic subtypes, proliferation marker Ki67, MVD according to CD34 staining, and total tumor volume. Results: Mean SUV, SUVmax, and the metabolic tumor volume (mL) were 5.8, 8.7, and 32.3, respectively, in adenocarcinoma and 8.5, 12.9, and 16.8, respectively, in SCC. Mean BF (mL/100 mL/min), mean BV (mL/100 mL), and K-trans (mL/100 mL/min) were 35.4, 7.3, and 27.8, respectively, in adenocarcinoma and 35.5, 10.0, and 27.8, respectively, in SCC. Moderate correlations were found between the F-18-FDG PET/CT parameters and Ki67 as well as between CT perfusion parameters and MVD but not vice versa. For all tumors, the following correlations were found: between SUVmax and Ki67, r = 0.762 (P = 0.017); between SUVmax and MVD, r = -0.237 (P = 0.359); between mean BF and Ki67, r = -0.127 (P = 0.626); and between mean BF and MVD, r = 0.467 (P = 0.059). Interestingly, correlations between the BF-metabolic relationship and total tumor volume were higher in SCC (r = 0.762, P = 0.017) than in adenocarcinoma (r = -0.0791, P = 0.788). Conclusion: F-18-FDG uptake correlates with Ki67, whereas BF, BV, and K-trans correlate with MVD. Therefore, F-18-FDG uptake and perfusion parameters provide complementary functional information. An improved tumor profiling will be beneficial for both prognosis and therapy response evaluation in these tumors.