Exophytic is a descriptive term used by radiologists/pathologists to describe solid organ lesions arising from the outer surface of the organ of origin.
Literally exophytic only refers to those lesions arising from the outer surface, however radiologists and pathologists use the term to include those lesions that arise deeper within the organ of origin but whose center lies outside the organ. Others use a looser definition and include those lesions with their centers within the organ, but which protrude from the surface. Other radiologists for the latter lesions qualify the term and state "partially exophytic".
It is commonly seen in the description of renal cysts or hepatic lesions.
History and etymology
Exophytic is derived from the Ancient Greek roots: εξω (exo) meaning 'outer' and φυτον (phuton) meaning 'plant', as the term exophyte in botany refers to a parasite that grows on the outside of a plant 2.
- 1. Kim HJ, Lee DH, Lim JW, Ko YT, Kim KW. Exophytic benign and malignant hepatic tumors: CT imaging features. (2008) Korean journal of radiology. 9 (1): 67-75. doi:10.3348/kjr.2008.9.1.67 - Pubmed
- 2. Wiktionary. "Exophyte". Wiktionary.org. https://en.wiktionary.org/wiki/exophyte#English (accessed July 18, 2018).