title: Malignant transformation of meningeal melanocytoma: a case report.
abstract: Intracranial meningeal melanocytoma is an uncommon tumor that is considered benign. We formerly reported an intracranial meningeal melanocytoma. Here we report a extremely rare case of malignant transformation of this tumor. A 49-year-old man complained of a headache. Magnetic resonance scanning revealed a mass in the left frontal region. The patient underwent gross total removal of the tomor in 1994. The histological findings showed a meningeal melanocytoma. In 1998, he underwent gamma-knife surgery for local recurrence. An additional operation was performed in 1999 became tumor growth was not stopped. The tumor was partially excised by left frontal craniotomy. Histopathological examination revealed a malignant melanoma originating from a melanocytoma. The tumor was composed of a proliferation of severely atypical melanocytoid cells with slightly irregular nuclei and prominent nucleoli, associated with necrosis and hemorrhage. Mitotic figures were encountered occasionally. After six months, he died from cerebrospinal fluid dissemination of this tumor. To our knowledge, this is the first report of malignant transformation of an intracranial meningeal melanocytoma.
authors: Department of Neurosurgery, Fukuoka Tokushukai Hospital, Sukukita 4-5, Kasuga, Fukuoka 816-0864, Japan.
authors: Yoichi
authors: Y
authors: Uozumi
authors: Teruaki
authors: T
authors: Kawano
authors: Tsutomu
authors: T
authors: Kawaguchi
authors: Yoshirou
authors: Y
authors: Kaneko
authors: Takao
authors: T
authors: Ooasa
authors: Sadanobu
authors: S
authors: Ogasawara
authors: Hidenori
authors: H
authors: Yoshida
authors: Takahisa
authors: T
authors: Yoshida
mesh_terms: D001932:Brain Neoplasms / Q000556:secondary; D002471:Cell Transformation, Neoplastic / Q000473:pathology*; D017809:Fatal Outcome; D006801:Humans; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging; D008297:Male; D008545:Melanoma / Q000378:metabolism / Q000473:pathology* / Q000556:secondary / Q000648:ultrastructure; D020460:Melanosomes / Q000648:ultrastructure; D008577:Meningeal Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000648:ultrastructure; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology*; D013120:Spinal Cord Neoplasms / Q000556:secondary