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What is Schwannoma, the marked area represents and explain in detail?
Schwannoma Well circumscribed, encapsulated masses that are attached to a nerve but can be separated from it (Whereas neurofibromas are unencapsulated, an ill circumscribed mass that presents within the nerve and expanding them, hence the tumor cannot be separated from the nerve)Microscopic findings :Two patterns - Antoni A and Antoni B patterns Antoni A - Cellular with spindle cells showing nuclear palisades. There is an alternate array of nuclear palisades and nuclear-free zones were together called "Verocay bodies"Antoni B - Less densely cellular and consists of a loose meshwork of cells, microcysts, and myxoid stroma.Ref: Robbins 8/e p1340