Metabolic evaluation of non-small cell lung cancer patient-derived xenograft models using 18F-FDG PET: A potential tool for early therapy response

Lung cancer heterogeneity makes response to therapy extremely hard to predict. Patient-derived xenografts (PDXs) are a reliable preclinical model that closely recapitulates the main characteristics of the parental tumors and may represent a useful asset for testing new therapies. Here, using PET imaging, we investigated whether lung cancer PDXs reproduce the metabolic characteristics of the corresponding parental tumors. Methods: We performed longitudinal 18FFDG PET studies on 9 different PDX groups obtained by implanting primary-cancer fragments harvested from patients into mice. The SUVmax of each PDX was calculated and compared with the SUVmax of the corresponding parental tumor. Results: Tumor growth rate and uptake varied among the different PDXs and confirmed the preservation of individual characteristics. The intragroup reproducibility of PET measurements was good. Furthermore, PDXs from tumors with a higher metabolic rate displayed a rank order of uptake similar to that of the parental tumors. Conclusion: PDXs reproduced the glucose metabolism of the parental tumors and therefore represent a promising preclinical model for the early assessment of therapy efficacy.