MRIで特徴的な像を呈した小児腹膜リンパ腫症（peritoneal lymphomatosis）の1例

A case of peritoneal lymphomatosis in a child with a characteristic appearance on MRI

腹膜リンパ腫症（peritoneal lymphomatosis：PL）は，びまん性の腹膜，大網，腸間膜病変を特徴とする非ホジキンリンパ腫（non-Hodgkin lymphoma：NHL）のまれな病態であり，PLで発症したリンパ腫の節外浸潤は一般的に予後不良とされている^1-3）。PLをきたした症例は大多数が成人であると報告されており，小児発症例は少ない^4）。

We experienced a rare case of peritoneal lymphomatosis in a 5-year-old girl and investigated its morphological characteristics. The tumor diffusely infiltrated the peritoneum and omentum, had smooth margins, and had a relatively smooth parenchyma, without showing nodular or lumpy morphology. The morphological characteristics were clearly depicted by MRI. Administration of anticancer drugs for lymphoma, primarily steroids, led to a significant reduction in tumor size approximately two weeks after treatment. We report a case of pediatric malignant lymphoma in which characteristic imaging findings suggested the possibility of peritoneal lymphomatosis, enabling its early diagnosis and treatment.