下列有關胸腺瘤（thymoma）之Masaoka staging之敘述，何者錯誤？
Stage IVa：胸腔外轉移
Stage I：腫瘤之capsule完整，無capsule invasion
Stage II為capsule invasion
Masaoka Stage III為macroscopic invasion至周圍的器官，如心包膜、大血管或肺
