Prognostic Role of the Platelet-to-Lymphocyte Ratio for Patients With Metastatic Colorectal Cancer Treated With Aflibercept.

Background/Aim: The efficacy of aflibercept plus 5-fluorouracil, leucovorin and irinotecan (FOLFIRI) therapy has been demonstrated in patients with metastatic colorectal cancer (mCRC) in global and Japanese clinical trials. However, a practical biomarker to predict its efficacy is lacking. Patients and Methods: This was a single-institution retrospective study of 21 patients with mCRC consecutively treated with aflibercept plus FOLFIRI from March 2018 to July 2019. We investigated the association and predictive value of pretreatment blood inflammation and immune-based scores, including the neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio (PLR), and lymphocyte-monocyte ratio, using their median values as cut-offs, in regard to disease control (DC), progression-free (PFS), and overall (OS) survival. Results: The number of patients in each treatment line of aflibercept was as follows: Second, 14 (66.7%); third, four (19.0%); fourth, two (95%); eighth, one (4.8%). The median number of aflibercept treatment courses was seven (range=2-17). The median follow-up time was 391 days. In univariate analysis, patients with DC had a signcantly lower PLR than those without DC. Only the PLR was significantly negatively associated with PFS, but not with OS. Multivariate analysis showed a significantly poor prognostic impact of a high PLR on PFS (hazard ratio=10 28; p=0.003). Conclusion: A low pretreatment PLR might be a predictor of aflibercept efficacy in patients with mCRC and may be clinically useful for selecting patient responders.