Plasma VEGF-D and PlGF levels according to prior use of biologics among metastatic colorectal cancer: Preliminary results from GI-SCREEN CRC-Ukit study.

Abstract

178 Background: Plasma vascular endothelial growth factor-D (VEGF-D) level is a potential predictor for ramucirumab efficacy in patients (pts) with metastatic colorectal cancer (mCRC), while a high VEGF-A and placental growth factor (PlGF) level in bevacizumab naïve pts receiving 2nd-line FOLFIRI plus aflibercept may suggest relatively higher activity. However, there are a few data associating 1st-line antiangiogenic treatments as well as anti-EGFR with angiogenic factors. Methods: This prospective longitudinal study aims to investigate an association between plasma angiogenesis-related mediators and clinical outcomes in mCRC. Serial plasma collections were done at time points of pre- and post-treatments of either 1st- or 2nd-line. Comprehensive measurements of 17 mediators were analyzed by the multiplex assay with Luminex technology. Here we report an association between levels of VEGF-D, PlGF and patient backgrounds. Results: From Sep 2017 to Aug 2019, 375 samples from 317 pts were enrolled in this analysis. Baseline characteristics were follows; 169 samples at pre-1st-line (pre-1L), 151 with prior bevacizumab treatment (post-bev) and 55 with prior anti-EGFR antibody (post-EGFR); median age, 66 years; male gender, 58%; RAS mutant, 46%; left-sided primary, 76%. In pre-1L, the median values of VEGF-D/ PlGF were 264/ 7.21 pg/mL without a clear association between the two in each patient (r = 0.094) and any baseline characteristics. Compared to pre-1L, the values of VEGF-D/ PlGF showed significantly higher in post-bev (median VEGF-D/ PlGF; 346/ 23.5 pg/mL, respectively). Moreover, there was no clear relationship between the two cytokines in each patient (r = 0.190). In 37 pts with serial blood collection, VEGF-D/ PlGF levels showed similar trends. In addition, VEGF-D/ PlGF levels in post-EGFR tended to be higher than those in pre-1L (median VEGF-D/ PlGF; 395/ 9.11 pg/mL, respectively). Conclusions: The VEGF-D/ PlGF may be separately induced by bev treatment as well as anti-EGFR therapy, suggesting the possibility of usefulness for selecting a better antiangiogenic inhibitor by measuring baseline VEGF-D/ PlGF. Clinical trial information: UMIN000028616.