PMEL and neoplasm: The expression of the MITF regulated melanocytic antigens (HMB-45/gp100 and Melan-A/MART-1, Figure 2A) and S-100 (data not shown) was assessed by immunohistochemistry on pre- (surgery December-2010 and November-2011) and post-sunitinib tumor specimens (surgery April-2012).