Serum neuron-specific enolase in metastatic Merkel cell tumors

Three patients with widely disseminated Merkel cell tumors of the skin are presented. In all three cases, neuron-specific enolase (NSE) was demonstrated in neoplastic tissue by immunohistochemical staining, and serum NSE levels were also elevated in all three patients. Serum NSE may prove to be a useful tumor marker in this and other malignancies of neuroendocrine origin.