Editing Brain tumor (section)

===Pathology===
[[File:Oligodendroglioma1 high mag.jpg|thumb|[[Micrograph]] of an [[oligodendroglioma]], a type of brain cancer. Brain [[biopsy]]. [[H&E stain]].]]
Maximal safe surgical resection (to preserve as much neurological function as possible) and histologic examination of the tumor is also required to aid in the diagnosis.<ref name="Schaff 2023" /> Cancer cells may have specific characteristics.

[[Atypia]]: an indication of abnormality of a cell (which may be indicative of malignancy). Significance of the abnormality is highly dependent on context.<ref>{{Cite journal | vauthors = Watson AN |date=2007-01-01 |title=Significance of "Atypia" Found on Needle Biopsy of the Breast: Correlation with Surgical Outcome |url=https://elischolar.library.yale.edu/ymtdl/384 |journal=Yale Medicine Thesis Digital Library}}</ref>

[[Neoplasia]]: the (uncontrolled) division of cells that is characteristic of cancer.<ref>{{cite web |title=Neoplasia |url=https://www.cancer.gov/publications/dictionaries/cancer-terms/def/neoplasm |website=www.cancer.gov |publisher=National Cancer Institute |language=en |date=2 February 2011}}</ref>

[[Necrosis]]: the (premature) death of cells, caused by external factors such as infection, toxin or trauma. Necrotic cells send the wrong chemical signals which prevent [[phagocyte]]s from disposing of the dead cells, leading to a buildup of dead tissue, cell debris and toxins at or near the site of the necrotic cells<ref name=necrs>{{MedlinePlus|002266|Necrosis}}</ref>

Local [[hypoxia (medical)|hypoxia]], or the deprivation of adequate oxygen supply to certain areas of the brain, including within the tumor, as the tumor grows and recruits local blood vessels.<ref>{{cite journal | vauthors = Emami Nejad A, Najafgholian S, Rostami A, Sistani A, Shojaeifar S, Esparvarinha M, Nedaeinia R, Haghjooy Javanmard S, Taherian M, Ahmadlou M, Salehi R, Sadeghi B, Manian M | title = The role of hypoxia in the tumor microenvironment and development of cancer stem cell: a novel approach to developing treatment | journal = Cancer Cell International | volume = 21 | issue = 1 | pages = 62 | date = January 2021 | pmid = 33472628 | pmc = 7816485 | doi = 10.1186/s12935-020-01719-5 | doi-access = free }}</ref>