Neurological Surgery 脳神経外科43巻9号

2015年09月発行

症例

Pilomyxoid-spectrum astrocytoma 2例の臨床病理学的検討—BRAF遺伝子異常の検討も加えて

著者： 伊東民雄¹ 佐藤憲市¹ 及川光照¹ 杉尾啓徳¹ 浅野目卓¹ 尾崎義丸¹ 中村博彦¹ 田中伸哉² 津田真寿美² 長嶋和郎³

所属機関： ¹中村記念病院脳神経外科，脳腫瘍センター ²北海道大学大学院医学研究科腫瘍病理学分野 ³札幌東徳洲会病院病理診断科

ページ範囲：P.825 - P.833

Ⅰ．はじめに
　Pilomyxoid astrocytoma（PMA）はbiphasic patternをとるpilocytic astrocytoma（PA）とは異なり，背景はmonophasicなmyxoid patternをとる腫瘍として1999年にTihanらにより提唱された¹⁹⁾．2007年のWHO脳腫瘍分類では，PMAはPAと比べて乳幼児に発生し予後も悪いことからGrade Ⅱとして分類されている¹⁷⁾．しかしながらPMAは再発時にPAにmatureしたという報告が散見され^1,12)，2010年にJohnsonらは両者は一連のspectrum上にあるとして“intermediate pilomyxoid tumors（IPTs）”の概念を提唱している¹²⁾．
　一方，PAではBRAF遺伝子異常（KIAA1549-BRAF fusion）が約70%にみられるが^{3,4,7,8,11,15)}，PMAでの報告は少ない．今回われわれはPMAおよびIPT，すなわちpilomyxoid-spectrum astrocytoma（PMSA）と考えられた2例を経験したので，その臨床病理像をBRAF遺伝子異常の検討も加え報告する．

参考文献

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