頭蓋咽頭腫—ドライバー遺伝子の解明による新時代の幕開け

Craniopharyngiomas: The Dawn of a New Era with the Elucidation of Driver Genes

Point

・頭蓋咽頭腫はドライバー遺伝子が解明され，WHO脳腫瘍分類第5版では，エナメル上皮腫型，扁平上皮乳頭型がそれぞれ独立したチャプターとして取り扱われるようになった．

・扁平上皮乳頭型頭蓋咽頭腫に対するBRAF・MEK阻害薬の前向き臨床試験にて良好な治療成績が示された．

・頭蓋咽頭腫に対する外科的治療のあり方が問われる時代になっている．

　Craniopharyngiomas（CPs）are primary brain tumors that emerge from the remnants of Rathke's pouch. Despite their histologically non-malignant nature, the proximity to major blood vessels and hypothalamus, as well as the infiltrative growth, make total resection challenging. CPs are classified into two pathological subtypes: adamantinomatous（ACP）and papillary（PCP）. CTNNB1 mutations were detected in ACPs, and the BRAF V600E mutation was detected in PCPs. Although both subtypes are epithelial tumors, they have different genetic profiles, clinical presentations, imaging findings, and histopathology. They are mentioned as independent chapters in the World Health Organization Classification of Tumors of the Central Nervous System, 5th edition. In 2023, a prospective clinical trial investigating a BRAF/MEK inhibitor for craniopharyngioma with BRAF mutations demonstrated marked tumor shrinkage. Currently, attempts are being made to elucidate the predictors of BRAF mutations to facilitate the use of neoadjuvant chemotherapy for craniopharyngioma. Additionally, the management of craniopharyngiomas requires the development of a surgical strategy that considers radiation and molecular-targeted therapies.