Tumor

A tumor was a type of abnormal growth of tissue, often found in one's brain. Clone trooper CT-5385, known as Tup, had a tumor in his brain which damaged his inhibitor chip and lead to it malfunctioning. The medical droid that discovered the tumor in Tup's brain, AZI-3, saw the tumor as rare in the clone's kind.

Text and facts from the “Tumor” article on Wookieepedia, licensed under CC BY-SA 3.0. Modified for this site.