術前診断が困難であった腹膜中皮腫の1例

A case of peritoneal mesothelioma where preoperative diagnosis was difficult

中皮腫は胸膜，腹膜，心膜，精巣鞘膜に発生するまれな悪性腫瘍で，腹膜発生は胸膜に次いで高頻度である。石綿曝露との関連からも注目され，患者数は年々増加傾向であり，予後不良な疾患である。今回我々は，腹膜に多発する腫瘤として過去の報告とは異なる画像所見を示した腹膜中皮腫の1例を経験したので，文献的考察を加えて報告する。

Peritoneal mesothelioma（PM）is a rare malignancy accounting for 7.8％ of mesotheliomas, typically diagnosed at advanced stages with poor prognosis. Patients are younger than those with pleural mesothelioma, show a relatively higher female ratio, and only 30-50％ have asbestos exposure with shorter latency. Imaging is classified into dry, wet, and combined types；dry type features peritoneal nodules with little ascites and prolonged enhancement. We report a dry-type PM with multiple small diaphragms and omental nodules that are strongly enhanced from the early phase, which was difficult to differentiate from other peritoneal tumors.