Neurogenic Tumors of the Mediastinum

Neurogenic tumors represent a broad ill-defined category of neoplasms that includes tumors of Schwann cell and/or neuroblastic derivation, as well as neoplasms that typically develop in the central nervous system, but rarely present in ectopic sites including the mediastinum. Neurogenic tumors may occur at many different anatomic sites, but the mediastinum represents a uniquely challenging site given the complex anatomy. Additionally, some of these neoplasms may present with multicentric involvement in the context of genetic syndromes, including NF1, NF2 and schwanomatosis. Most of these develop in posterior structures, often in association with paraspinal structures. Fine needle biopsy/small biopsies play an important role in the diagnosis of these neoplasms, given its record of safety and the increased applicability of ancillary testing to these smaller samples at the present time. In this review we focus on the major categories of neurogenic tumors that may be encountered in the mediastinum, including schwannoma, neurofibroma, malignant peripheral nerve sheath tumors, ganglioneuroma and ganglioneuroblastoma, as well as rarer members of this category. We discuss diagnostic approaches applicable to small cytologic and tissue samples and relevant differential diagnoses.