Phantom organ sign
The phantom organ sign is a term used when a large mass arises from a small organ and as a consequence, it is impossible to detect the affected organ.
The identification of this sign and other radiological signs such as the embedded organ sign, beak sign, and prominent feeding artery sign on CT or MRI is particularly useful in localizing masses from retroperitoneal organs. On the contrary, the absence of these signs supports the possibility of a primary retroperitoneal tumor 1.
Some false positive of the phantom organ sign has been reported such as the case of huge retroperitoneal sarcomas involving the adrenal glands 1.
- 1. Mizuki Nishino, Katsumi Hayakawa, Manabu Minami, Akira Yamamoto, Hiroyuki Ueda, Kosho Takasu. Primary Retroperitoneal Neoplasms: CT and MR Imaging Findings with Anatomic and Pathologic Diagnostic Clues1. (2003) RadioGraphics. 23 (1): 45-57. doi:10.1148/rg.231025037 - Pubmed
- 2. Mota MMDS, Bezerra ROF, Garcia MRT. Practical approach to primary retroperitoneal masses in adults. (2018) Radiologia brasileira. 51 (6): 391-400. doi:10.1590/0100-3984.2017.0179 - Pubmed