Neurone specific enolase and S100 protein as possible prognostic indicators in melanoma*

Abstract

Fourteen cases of primary melanoma and 25 of their subsequent metastases were stained for neuron specific enolase (NSE) and S100 protein. Intensity of staining for NSE and S100 protein broadly corresponded in II of the primary lesions and was disparate in 3. Staining intensity for NSE or S100 was independent of tumor thickness. Primary lesions showing marked or moderate staining for NSE and S100 protein took a shorter time to metastasize than those showing slight or no staining. Assessment of staining intensity for NSE and S100 thus identified prognostic categories corresponding to disease free interval obtained by division according to tumor thickness. Staining intensity for S100 protein appears to give a clearer indication as to expectation of disease free interval. Staining intensity in individual cases showed an increase both for NSE and S100 protein between primary and metastatic lesions. The data presented are not sufficient to assign statistical significance but may lead to the incorporation of functional studies into the pathological assessment of malignant melanocytic lesions. The simultaneous occurrence of a functional neuronal and Schwann cell marker in melanoma is discussed.