title: Malignant neuroendocrine tumor presenting a huge mediastinal mass controlled with radiation therapy.
abstract: A case of malignant neuroendocrine tumor presenting a huge mediastinal mass controlled with radiation therapy is reported. A thoracotomy was performed on a 57-year-old male and a mass was found to invade the trachea, main bronchus, and left atrium. The tumor was unresectable. Subsequently, cisplatin was administered, but the tumor grew in size and radiation therapy was recommended. The tumor responded well to thoracic irradiation (56 Gy) and disappeared. Three months later, lymph nodes metastases were noted in the retrocrural and upper abdominal paraaortic regions, but these were controlled again with palliative irradiation. Without further treatment, he survived free of disease for over 5 years. Specimens obtained during the thoracotomy showed that the tumor consisted mainly of small round cells with a rosette formation. Immunohistochemically the tumor was positive to NSE and slightly positive to keratin, but negative to LCA, L26, UCLH-1, EMA, Leu7, and chromogranin, suggesting a malignant tumor derived from neuroendocrine tissue.
authors.affiliation: Department of Radiology and Radiation Oncology, Gunma University School of Medicine, Maebashi, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Furuta
authors.forename: K
authors.initials: K
authors.lastname: Hayakawa
authors.forename: S
authors.initials: S
authors.lastname: Kato
authors.forename: N
authors.initials: N
authors.lastname: Mitsuhashi
authors.forename: T
authors.initials: T
authors.lastname: Nakajima
authors.forename: H
authors.initials: H
authors.lastname: Niibe
mesh_terms: D003937:Diagnosis, Differential; D004307:Dose-Response Relationship, Radiation; D006801:Humans; D008297:Male; D008479:Mediastinal Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy*; D008875:Middle Aged; D018358:Neuroendocrine Tumors / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy*; D010166:Palliative Care; D011859:Radiography