Tumor-like formation localized in any anatomical area resulting from abnormal growth of benign tissue, in medicine is defined as hamartoma (from Greek hamartia - error, defect).
A medical term such as "piloid astrocytoma" is used to refer to neoplasms formerly referred to as cystic cerebral astrocytomas, either hypothalamic-parietal gliomas or juvenile pilocytic astrocytomas.
Among the many tumor processes of the central nervous system most often diagnosed glioma of the brain - this term is a collective, the neoplasm combines all diffuse oligodendroglial and astrocytic foci, astrocytoma, astroblastoma and so on.
A benign tumor process, neurinoma of the brain and spinal cord, originates from lemmocytes. These are so-called Schwann structures, auxiliary nerve cells formed along the course of the axons of peripheral nerves.
