頭頸部悪性腫瘍の治療後に発症した骨髄異形成症候群の1例

A Case of Secondary Myelodysplastic Syndrome after Treatment for Malignant Lymphoma

　はじめに

　骨髄異形成症候群（myelodysplastic syn-drome：以下，MDSと略）は造血幹細胞の障害の結果，無効造血をきたし，貧血，穎粒球減少症，血小板減少症が様々な程度に起こる疾患である^1,2）。前白血病としての特徴をもつ疾患で，緩徐に発症し初期には無症状か，あっても軽度の貧血症状が大部分であるが，進行すれば白血病化が知られ^1），その発症機序や取り扱いについてはまだ未解決の部分がある。本症候群は中高齢者に多く，貧血から始まる症例が多く，高齢者の貧血をみた際の鑑別疾患の1つである^2）。特発性および続発性のものが認められ，続発性は治療誘発性ともいわれ，放射線曝露，化学療法薬などが原因とされている^1）。今回われわれは，悪性リンパ腫の加療後2年を経て喉頭炎をきたし，その入院中に治療誘発性MDSと思われた症例を経験したので報告する。

A 78-year-old man with pharyngeal pain had a past history of chemotherapy and irradiation for malignant lymphoma at age of 76. There was an ulcer of the epiglottis and recurrence of malignant lymphoma was suspected.

After direct laryngoscopy epiglottitis due to MRSAand Candida infections without lymphoma was diagnosed. He had anemia and hypogranulocytosis in blood examination and his severe epiglottitis was diagnosed as myelodysplastic syndrome which was made from bone marrow findings, showing myelo-blasts (5%) and hypoplastic erythroid system. A chromosomal banding study of the bone marrow cells showed abnormal band in a few cells. The patient received irradiation and chemotherapy for malignant lymphoma, and his myelodysplastic syn-drome was considered to be secondary to these therapeutic measures.