Relevance of MIA and S-100 to monitor BRAF inhibitor (iBRAF) therapy in metastatic melanoma patients.

9074 Background: MIA and S-100 have been proposed as tumor markers for patients with melanoma, but they are not widely accepted. BRAF V600E mutation has been reported in more than 50% of melanomas. Recently, selective BRAF inhibitors have proved to be more active than DTIC in first line treatment of BRAF V600E melanoma patients. The aim of the present work is to evaluate the utility of MIA and S-100 during iBRAF treatment. Methods: BRAF V600E mutation was analyzed in 77 patients with metastatic melanoma by automated direct sequencing in tumor DNA. Tumor markers (MIA, S-100 and LDH) were studied in serum from all patients. Sixteen of these patients received iBRAF therapy (11 Vemurafenib, 5 Dabrafenib) and tumor markers were analyzed sequentially: baseline, best response and progression. MIA and S-100 were determined by immunometric methods and LDH by a spectrophotometric assay. The cut-off points were MIA=9 ug/L, S-100=0.1 ug/L, and LDH=290 U/L. Non-parametric statistical analysis was performed. Results: F...