Epithelioid blue nevus and psammomatous melanotic schwannoma: the unusual pigmented skin tumors of the Carney complex.

Carney complex, a familial multitumoral syndrome, comprises spotty skin pigmentation (lentigines and blue nevi), myxomas (heart, skin, and breast), endocrine tumors (adrenal cortex, pituitary, testis, and thyroid), and schwannomas. The skin pigmentary abnormality included two unusual conditions, epithelioid blue nevus and psammomatous melanotic schwannoma. The former tumor occurred on the extremities and trunk, less frequently on the head and neck; was multiple; and did not recur or metastasize. Clinically, it was pigmented, domed, and small (< 1 cm). Microscopically, it displayed two types of melanocytes--one intensely pigmented, globular, and fusiform and the other lightly pigmented, polygonal, and spindle. Nuclei of the latter cells were vesicular, with pale chromatin and single prominent nucleolus. None recurred or metastasized. The psammomatous melanotic schwannoma occurred in posterior spinal nerve roots, upper alimentary tract, bone, and skin. Microscopically, it was circumscribed but incompletely encapsulated and contained spindle and epithelioid cells, melanin, psammoma bodies, and fat. The spindle cells were arranged in interlacing fascicles, with whorling and occasional nuclear palisading. Twenty-one patients (68%) were alive without evidence of the neoplasm; two of these each had two local recurrences. Seven patients died, three (10%) as a result of metastasis.