Journal of Clinical Oncology | 2019
Association of consensus molecular subtypes (CMS) with time to progression (TTP), progression free survival (PFS), and overall survival (OS) with second-line FOLFIRI ± regorafenib in metastatic colorectal cancer (mCRC).
Abstract
597Background: LCCC1029 was a 2:1 randomized phase II trial of second-line FOLFIRI plus either regorafenib or placebo in mCRC that showed no statistically significant difference in PFS or OS. CMS, defined using gene expression, is prognostic for PFS and OS in previously untreated mCRC, but the impact of CMS in second-line treatment is unclear, as well as its impact on regorafenib efficacy. Methods: RNAseq on archival tumor tissue was successfully performed in 68 LCCC1029 patients (49 on regorafenib, 19 on placebo). A multinomial elastic net CMS classifier was trained using 6 CRC gene expression data sets with known CMS classification. We built our model with only CMS1-4 classified samples and then applied it to normalized and median adjusted RNASeq from LCCC1029 to classify all samples into CMS1-4. TTP, PFS, and OS were compared using Kaplan-Meier method and log-rank tests, and hazard ratios were estimated using Cox proportional hazards method. Results: Our model had > 93% sensitivity and specificity for ...