Quantitative Multiplex Immunofluorescence Evaluation of the Tumor Microenvironment in Pretreatment Tumors of Patients with Metastatic Breast Cancer and Serous Ovarian Carcinoma Treated with Liposomal Eribulin.

Eribulin inhibits microtubule polymerization and suppresses epithelial-mesenchymal transition. Conventional pathology approaches have not identified a precise predictive biomarker for Eribulin. We performed qmIF on pre-treatment tissue from 11 patients (6 TNBC, 5 HGSOC) treated with Eribulin-LF. T-lymphocytes were the dominant immune-subset in TME, with higher levels detected in stroma vs tumor (9% vs 2%). Greater density of CD3+ ( p  = 0.01) and CD3 + CD8+ ( p  = 0.03) cells and closer proximity between CD3 + CD8+ and tumor cells was observed in the patients with disease control (PR + SD) vs. progressive disease. QmIF identified an association between TIL infiltration and Eribulin-LF sensitivity, which should be evaluated further in prospective studies.