A malignant nerve sheath tumor occurred in the thigh of a 29-year-old man who had the stigmata of von Recklinghausen's neurofibromatosis. Chondroid foci, rhabdomyoblasts, and mucus-containing acini were identified in the tumor. Argyrophil cells and somatostatin-immunoreactive cells were present in acinar epithelium. Endocrine type granules were found in epithelial cells on ultrastructural examination. This is an example of a so-called "glandular schwannoma" and is unique in that it contained somatostatin-immunoreactive cells. A neural crest derivation is suggested for this complex tumor.