Neuroendocrine Tumors of the Mediastinum

Analogous to other organ systems, neuroendocrine tumors arising in the mediastinal compartment comprise a group of diverse neoplasms, ranging from indolent to highly aggressive lesions. These include tumors in the spectrum of primary thymic neuroendocrine carcinomas as well as mediastinal paragangliomas and ectopic parathyroid tumors. Overall, such lesions are very rare, accounting for less than 5% of all mediastinal neoplasms. Among these, neuroendocrine carcinomas, especially the low and intermediate grade types (carcinoid and atypical carcinoid tumors), are the most common and prone to be mistaken for more indolent neoplasms. In this context, familiarity with lesions that share similar morphological and immunohistochemical features becomes highly important as the prognosis of these lesions may differ significantly.