頭蓋内外に腫瘍性病変を形成した慢性リンパ性白血病の一例

Abstract

症例は 81 歳男性．羞明症状を主訴に近医を受診し，血液検査にてリンパ球著増，頭部単純 CT にて頭蓋占拠性病変を指摘さ れた．血液疾患が疑われ当科紹介，精査入院．血液検査にて白血球数 104240/μl（リンパ球 97.5％），骨髄検査にて小?中型の 成熟異型リンパ球を 96.8％認め，フローサイトメトリーの結果から慢性リンパ性白血病（ CLL ）と診断した．MRI で頭蓋内， 頭蓋骨外皮下，後頚部，眼窩部に拡散制限を伴う腫瘍性病変を認め，皮下結節生検では白血病浸潤の所見，髄液中にも白血病 細胞を認めた．以上よりこれらも白血病病変と診断した．週 1 回の髄注および cyclophosphamide 連日内服を開始し，髄液所見 は著明な改善を認めたが，感染症により死亡．CLL の髄外腫瘤及び中枢神経浸潤は非常に珍しく，さらなるデータの蓄積が期 待される．

An 81-year-old man visited his local doctor with a complaint of photophobia. His blood test showed marked increase in lymphocytes, and plain computed tomography scan of the head showed occupying cranial lesions. He was referred to our hematology department and hospitalized for further examination. His blood test showed a white blood cell count of 104,240 /μl (97.5% lymphocytes), and 96.8% of bone marrow cells were small to medium-sized mature atypical lymphocytes. Based on the results of flow cytometry our diagnosis was chronic lymphocytic leukemia (CLL). Magnetic resonance imaging showed neoplastic lesions with restricted diffusion in the intracranial, extracranial subcutaneous, posterior cervical, and orbital regions. The subcutaneous nodal biopsy showed infiltration of leukemia, and leukemic cells were observed in the cerebrospinal fluid (CSF). Based on these results, we diagnosed these lesions as leukemia. Weekly intrathecal infusion and daily oral cyclophosphamide administration were started, and the CSF findings improved significantly. However, he died of infection. Extramedullary tumors and central nervous system involvement of CLL are rare, and accumulation of further data is awaited.