Imaging of Nonlaryngeal Neuroendocrine Carcinoma

Summary: The imaging and pathologic features of three cases of nonlaryngeal neuroendocrine carcinoma of the head and neck are described. Neuroendocrine carcinomas represent malignant epithelial neuroendocrine neoplasms and are classified as three types: typical carcinoid (well differentiated), atypical carcinoid (moderately differenti-ated), and small cell neuroendocrine (poorly differentiated) carcinomas. The CT and MR imaging features of these tu-mors are nonspecific. Paranasal sinus neuroendocrine car-cinomas showed expansion and destruction of the sinus, whereas metastatic neuroendocrine carcinomas to an intra-parotid lymph node presented as a circumscribed parotid mass on CT scans. Neuroendocrine neoplasms have an epithelial or a neural origin (1). The true neuroendocrine tumors are those derived from the neurons and appropriate associated structures, such as the paraganglia of the peripheral nervous system (1). The term neuroen-docrine carcinoma encompasses a spectrum of malignant epithelial neuroendocrine neoplasms, ranging from atypical or well-differentiated to high-grade neoplasms (2, 3). Although most neu-roendocrine carcinomas are found in the lung and alimentary tract and its appendages, they have been found in almost every organ in the body (4). There are a number of reports on neuroendocrine tumors of the larynx in the literature (5–7), but we found no comprehensive reports on nonlaryngeal neuroen-docrine carcinomas. We present the radiologic and pathologic features of three cases of nonlaryngeal neuroendocrine carcinomas of the head and neck