Freebase(0.00 / 0 votes)Rate this definition: Arbol is a programming language which has been primarily developed for use in Genetic Programming experiments. It is a functional programming language inspired by the ideas of other small and esoteric languages.
Causes. In most cases of colon or rectal cancers, the cause or causes are unknown. Defects in genes that normally protect against cancer play the major role in causing polyp cells to continuously change and become cancerous.
Almost all colon cancers start in the lining of the colon and rectum. When doctors talk about colorectal cancer, this is usually what they are talking about. There is no single cause of colon cancer. Nearly all colon cancers begin as noncancerous (benign) polyps, which slowly develop into cancer.