巨大頭皮下腫瘤を形成した多発性骨髄腫の1例

A Case of Multiple Myeloma Associated with a Large Subcutaneous Mass in the Frontal Region

I．はじめに

　多発性骨髄腫は，骨髄で形質細胞が腫瘍性に増殖し，頭蓋骨，椎骨，肋骨，骨盤などに溶骨性変化をきたす疾患であるが，頭蓋，及び頭蓋内に巨大腫瘤を形成することは比較的少ない．多発性骨髄腫と診断され化学療法を受けた後6年経て，前頭骨，斜台部に腫瘤を形成した1症例を経験したので報告する．

A case of multiple myeloma having plasmacytoma in the frontal bone and clivus is reported. A 68-year-old female was referred to our hospital because of a sub-cutaneous mass in the frontal region. She was dia-gnosed as having multiple myeloma 7 years ago and had been treated with chemotherapy. On admission, se-vere anemia, hyperproteinemia and elevation of serum lambda type immunoglobulin G (IgG) were pointed out. Plain skull X-rays showed numerous punched out lesions with a large bone defect of the frontal bone. CT scan and MRI revealed a mass lesion in the clivus in addition to a large epidural tumor in the frontal region.The encapsulated frontal epidural tumor was totally re-sected and cranioplasty was performed with resin. His-tological diagnosis was plasmacytoma of IgG lambda type. The postoperative course was uneventful, and chemotherapy was continued. There was no tumor re-currence in the frontal region and no neurological de-terioration, but she died of DIC 15 months after the op-eration.

Twenty seven cases in the literature of multiple myeloma forming cranial or intracranial plasmacytoma were briefly reviewed. Although the prognosis of such cases is poor, total resection of medullary plasmacyto-ma is warranted especially in multiple myeloma pa-tients who don't have another extramedullary plas-macytoma or plasma cell leukemia.