Primary neuroendocrine (Merkel cell) carcinoma presenting in the calvarium: case report.

A case of a primary neuroendocrine carcinoma arising in the calvarium and involving the bone, dura, and underlying brain is presented. The histopathology and immunohistochemical staining characteristics of tumor were consistent with those of Merkel cell tumor. The natural history and histopathology of this tumor are discussed, along with the possible explanation for the origin of this tumor in the calvarium.