<unk> s may arise sporadically or in association with Neurofibromatosis type 2 as a result of mutations involving merlin protein. Loss of function of a tumor suppressor gene called merlin gene is noted commonly.<unk> s are composed of spindle cells which demonstrate two growth patterns Antoni type A and Antoni type B. Antoni type A pattern in which elongated cells are densely packed and arranged in fascicles. Palisades are sometimes seen, when prominent these form verocay bodies. Antoni type B pattern cells are less compact and are prone to cystic degeneration.<unk>  variants include ancient<unk> , cellular<unk> , melanotic<unk> , plexiform<unk> . Immunohistochemistry positive for S100, collagen IV, CD34, neurofilament protein, podoplanin, calretinin, Sox10. Associated conditions include neurofibromatosis type 2,<unk> tosis, carney's complex.
Schwannoma pathophysiology
Ganglioneuroma pathophysiology
Meningioma pathophysiology
Ganglioglioma pathophysiology
Lymphangioma pathophysiology
Paraganglioma pathophysiology
Glomus tumor pathophysiology
Ameloblastoma pathophysiology