横紋筋肉腫治療後26年で発症した放射線誘発性軟骨肉腫の1例

Radiation-induced Chondrosarcoma Arising 26 Years after Radiation Therapy for Rhabdomyosarcoma. Case Report

　患者は26歳の女性である．横紋筋肉腫に対する放射線照射後26年経過して骨盤軟骨肉腫を発症した．片側骨盤切除術を施行し，hip transposition法で再建した．術後1年の現在，局所再発は認めず，装具着用で片松葉杖歩行が可能である．横紋筋肉腫の放射線照射後に軟骨肉腫を生じた報告は，渉猟し得た範囲では2例と極めて稀であった．放射線治療後は肉腫の発生も考慮し長期の経過観察が必要と考えられた．

　A 26-year-old woman developed a pelvic chondrosarcoma 26 years after radiation therapy for a rhabdomyosarcoma and was treated surgically by hemipelvectomy and reconstruction by a hip transposition procedure.　There is no evidence of recurrence as of one year after surgery, and the patient is able to walk with a hip orthosis, and a crutch.　Only two cases of radiation-induced chondrosarcoma after radiation therapy for a rhabdomyosarcoma have been reported in the English-language literature.　We recommend that patients be followed up long term after radiation therapy in order to enable early detection of radiation-induced sarcomas.