Published online Oct 16, 2015. doi: 10.12998/wjcc.v3.i10.915
Peer-review started: February 10, 2015
First decision: April 24, 2015
Revised: June 12, 2015
Accepted: August 28, 2015
Article in press: September 7, 2015
Published online: October 16, 2015
Primary mediastinal neuroendocrine tumors are a rare malignancy that accounts for < 10% of all mediastinal tumors. The case presented here involves a 52-year-old man who had been suffering for 3 mo from chronic cough, anorexia and substantial weight loss, as well as 2 wk of jaundice prior to his admission. A computed tomography scan showed a 4.3 cm × 6.6 cm mediastinal mass with multiple liver nodules scattered along both hepatic lobes. Endoscopic ultrasound showed a large heterogeneous hypoechoic mass at the mediastinum with multiple target-like nodules in the liver. Fine-needle aspiration specimens revealed numerous, small, round cells with hyperchromatic nuclei, scarce cytoplasm, and frequent mitotic features. Immunohistochemical study revealed positive results for AE1/AE3, CD56 and chromogranin A, with negative findings for synaptophysin, CK20, vimentin, CK8/18 and CD45. The patient was subsequently diagnosed with a poorly differentiated neuroendocrine carcinoma, small cell type. A bone marrow biopsy also revealed extensive involvement by the carcinoma.
Core tip: Neuroendocrine tumors are rare tumors that arise from the gastrointestinal tract and bronchopulmonary system. Primary mediastinal neuroendocrine tumors are exceptionally rare malignancies, accounting for < 10% of all mediastinal tumors. The common clinical manifestation of this rare tumor is a mediastinal mass, but the condition can mimic lymphoma in advanced cases. The liver is the most common site of metastasis.