Melanin-containing peripheral carcinoid of the lung.

A case report of a patient with peripheral bronchial carcinoid is presented. The tumor cells contained characteristic neurosecretory granules, filopodia and microvilli. Some cells contained both neurosecretory granules and the granular variant of melanosome. We suggest that the demonstration of melanosomes does not necessarily confirm the diagnosis of melanoma and that melanin be added to the long list of substances contained in carcinoid tumors.