S100B and melanoma: While several prognostic melanocytic biomarkers are available for melanoma such as the melanoma inhibitory activity (MIA) protein, lactate dehydrogenase (LDH), HMB 45, and Melan A/Mart 1, the S100B protein is regarded as being most useful since elevated serum levels of S100B correlate highly with poor patient response to therapies, increased cancer recurrence, and lower survival rates [4–7].