BRAF V600 mutation has been reported in more than 50% of melanoma cases and its 
presence predicts clinical activity of BRAF inhibitors (iBRAF). We evaluated the 
role of MIA, S100 and LDH to monitor iBRAF efficiency in advanced melanoma 
patients presenting BRAF V600 mutations. This was a prospective study of 
melanoma patients harboring the BRAF V600 mutation and treated with iBRAF within 
a clinical trial (dabrafenib) or as part of an expanded access program 
(vemurafenib). MIA, S100 and LDH were analyzed in serum at baseline, and every 
4-6 weeks during treatment. Eighteen patients with melanoma stages IIIc-IV were 
enrolled with 88.8% of response rate to iBRAF. Baseline concentrations of all 
the tumor markers correlated with tumor burden. MIA and S100 concentrations 
decreased significantly one month after the beginning of treatment and, upon 
progression, their concentrations increased significantly above the minimum 
levels previously achieved. MIA levels lower than 9 μg/L one month after the 
beginning of treatment and S100 concentrations lower than 0.1 μg/L at the moment 
of best response were associated with improved progression-free survival. In 
conclusion, MIA and S100 are useful to monitor response in melanoma patients 
treated with iBRAF.