[Intracranial and orbital extension of a nasal cavity adult T-cell leukemia: a case report].

Adult T-cell leukemia (ATL) is one kind of leukemia induced by human T lymphotropic virus type I (HTLV-I) infection. An unusual case of ATL is presented. A fifty-one-year-old male patient was admitted to our hospital because of nasal obstruction and blindness in the left eye. Imaging study revealed a mass lesion in the nasal cavity, the left paranasal sinus extending to the left orbit and intracranial frontal base. Biopsy of the mass from the paranasal sinus was carried out and the histological diagnosis was a granulomatous lesion with non-specific inflammation. The clinical impression of the lesion was lethal midline granuloma. After steroid therapy and 50 Gy of local radiotherapy, the patient's symptoms disappeared except for his blindness in the left eye. Imaging study revealed that the mass lesion had become smaller. In spite of local improvement, new lesions such as cervical lymph node swelling and multiple nodular shadows in the lung fields appeared on CT scan. Histological diagnosis of the biopsied cervical lymph node was T-cell dominant non-Hodgkin's lymphoma of the diffuse type. Serologically, anti-HTLV-I antibody was positive. Southern blot analysis of lymph node biopsy showed monoclonal proliferation of ATL cells. We made the diagnosis of our case as ATL. The patient died 16 months later despite repeated systemic chemotherapy with cyclophosphamide, vincristine, adriamycin, and prednisolone. ATL can involve the central nervous system (CNS) and manifest CNS symptoms. The neurosurgeon also should consider the CNS involvement of ATL especially in Japan.