title: Malignant transformation of intrathoracic ancient neurilemmoma in a patient without Von Recklinghausen's disease.
abstract: Malignant transformation of a neurilemmoma is an exceedingly rare event. We describe a case of intrathoracic ancient neurilemmoma undergoing a malignant change in a 39-yr-old man. The patient presented with right flank and chest pain for several months. Plain radiography and CT scan of the chest showed a soft tissue mass lesion at the extrapleural space with erosion of surrounding ribs at the right basal lung area. The excised mass was encapsulated and measured 4.5 x 3.5 x 2.3 cm. The cut surface showed grayish-white and glistening with a focal cystic change and hemorrhage. Necrosis was not seen. Histologically, the tumor showed the features of classic neurilemmoma composed of the Antoni type A and B areas with perivascular hyalinization. In addition, obviously histo-logically malignant foci manifested by presence of markedly increased cellularity with fascicular arrangement, active mitotic activity, hyperchromasia, and gradual loss of original neurilemmomatous feature were noted.
authors.affiliation: Department of Anatomical Pathology, Inha University Hospital, Incheon, Korea. ycchu@inha.ac.kr
authors.forename: Young Chae
authors.initials: YC
authors.lastname: Chu
authors.forename: Yong Han
authors.initials: YH
authors.lastname: Yoon
authors.forename: Hye Seung
authors.initials: HS
authors.lastname: Han
authors.forename: Jee Young
authors.initials: JY
authors.lastname: Han
authors.forename: Joon Mee
authors.initials: JM
authors.lastname: Kim
authors.forename: In Suh
authors.initials: IS
authors.lastname: Park
mesh_terms: D000328:Adult; D014408:Biomarkers, Tumor; D002471:Cell Transformation, Neoplastic; D003937:Diagnosis, Differential; D006801:Humans; D008297:Male; D009442:Neurilemmoma / Q000150:complications / Q000473:pathology*; D009456:Neurofibromatosis 1 / Q000150:complications / Q000473:pathology*; D013899:Thoracic Neoplasms / Q000209:etiology / Q000473:pathology*
chemical_list: D014408:Biomarkers, Tumor