Somatic mutations drive distinct imaging phenotypes in lung cancer.

Emmanuel Rios Velazquez, Chintan Parmar, Ying Liu, Thibaud P Coroller, Gisele Cruz, Olya Stringfield, Zhaoxiang Ye, G Mike Makrigiorgos, Fiona M M Fennessy, Raymond H Mak, Robert J Gillies, John Quackenbush, Hugo Aerts,

Cancer research, June 1, 2017

Tumors are characterized by somatic mutations that drive biological processes ultimately reflected in tumor phenotype. With regard to radiographic phenotypes, generally unconnected through present understanding to the presence of specific mutations, artificial intelligence (AI) methods can automatically quantify phenotypic characters by using predefined, engineered algorithms or automatic deep-learning methods, a process also known as radiomics. Here we demonstrate how imaging phenotypes can be connected to somatic mutations through an integrated analysis of independent datasets of 763 lung adenocarcinoma patients with somatic mutation testing and engineered computed tomography (CT) image analytics. We developed radiomic signatures capable of distinguishing between tumor genotypes in a discovery cohort (n=353) and verified them in an independent validation cohort (n=352). All radiomic signatures significantly outperformed conventional radiographic predictors (tumor volume and maximum diameter). We found a radiomic signature related to radiographic heterogeneity that successfuilly discriminated between EGFR+ and EGFR- cases (AUC=0.69). Combining this signature with a clinical model of EGFR status (AUC=0.70) significantly improved prediction accuracy (AUC=0.75). The highest performing signature was capable of distinguishing between EGFR+ and KRAS+ tumors (AUC=0.80) and, when combined with a clinical model (AUC=0.81), substantially improved its performance (AUC=0.86). A KRAS+/KRAS- radiomic signature also showed significant albeit lower performance (AUC=0.63) and did not improve accuracy of a clinical predictor of KRAS status. Our results argue that somatic mutations drive distinct radiographic phenotypes that can be predicted by radiomics. This work has implications for the use of imaging-based biomarkers in the clinic, as applied non-invasively, repeatedly and at low cost.

Copyright ©2017, American Association for Cancer Research.

Pubmed Link: 28566328

DOI: 10.1158/0008-5472.CAN-17-0122