出生直後よりカサバッハ・メリット現象を呈し，緊急手術が奏功したカポジ型血管内皮腫の1例

Kaposiform Hemangioendothelioma in a Neonate with Kasabach-Merritt Phenomenon: Successful Treatment by Emergency Surgery

はじめに

　カポジ型血管内皮腫（Kaposiform hemangioendothelioma：以下，KHE）は局所侵襲性のまれな脈管腫瘍である。大部分は新生児期から乳児期に診断され，約半数でカサバッハ・メリット現象（Kasabach-Merritt phenomenon：以下，KMP）と呼ばれる消費性凝固障害を呈して重篤な経過をたどる 1）～3）。KMPを呈するKHEの治療法としては多様な報告があり 4）～12），標準的治療法は定まっていない。今回われわれは，KMPを呈するKHE新生児例を経験した。経過，画像所見を他診療科とともに検討し，生後2日（日齢2）と超早期に腫瘍切除に踏み切り，良好な経過を得た。幼小児の脈管腫瘍の切除は出血のリスクが高く，KMP急性期の腫瘍切除は通常勧められない。しかし，内科治療が奏功しない症例や治療効果発現前に危機的な病態となった場合などに，腫瘍を切除できれば病態の速やかな改善と根治が期待できる。本疾患の臨床的特徴とその治療法について，文献的考察を加えて報告する。

　Kaposiform hemangioendothelioma （KHE） is a rare vascular neoplasm and an intermediate tumor type with locally aggressive characteristics. KHE may develop into life-threatening thrombocytopenia and consumptive coagulopathy, known as the Kasabach-Merritt phenomenon （KMP）. Multiple treatment regimens with varying success have been reported for KHE associated with KMP and systemic drug therapy is generally recommended, but no standard of care has been established. We present the case of a 2-day-old male infant with KMP from KHE that was life-threatening but successfully treated with surgery. Surgery is rarely an option for a KHE during the active phase of KMP because of the higher risk of blood loss and the possibility of worsening the patient’s hematological parameters. However, surgery can be an effective approach for tumors in which a complete and safe resection can be performed. A successful surgery can save the patient’s life when other medical treatment is ineffective or a critical condition has developed before drug therapy becomes effective. Timely and appropriate surgery should be considered an option for KHE.