Schmorl結節と鑑別に難渋した極めてまれな脊椎原発性平滑筋肉腫の1例

A extremely rare case of primary leiomyosarcoma of the spine mimicking Schmorl node

一般の平滑筋肉腫は骨盤内や腸間膜などの腹部臓器や後腹膜の平滑筋組織の存在しうる箇所に発生するが^1），骨原発の平滑筋肉腫が1965年にEvansとSanerkinによって初めて報告されている^2）。しかし，椎骨で発症した原発性平滑筋肉腫は極めて報告数が少なく，非常にまれな平滑筋肉腫である^3）4）。今回我々は，菌状息肉症の経過観察中に診断した第1腰椎の脊椎原発性平滑筋肉腫を経験したので，若干の文献的考察を加えて報告する。

A 60s female was suspected to have Schmorl node on the first lumbar vertebra after PET/CT during follow-up for mycosis fungoides. Seven months later, PET/CT and MRI showed worsening of the disease, and malignancy was suspected. After CT-guided biopsy, we diagnosed leiomyosarcoma pathologically. Upper gastrointestinal endoscopy, lower gastrointestinal endoscopy and hysterectomy for biopsy were performed to investigate the primary tumor but we were not able to obtain obvious findings. Therefore, we diagnosed primary leiomyosarcoma of the spine. Later, liver metastasis was found. We performed chemotherapy and radiotherapy as palliative care and she died two years after starting treatment.