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.
The exact causes are unknown, but colon cancer has several potential risk factors. Polyps. Colon cancer usually derives from precancerous polyps that exist in the large intestine. The most common types of polyps are: Adenomas: These can resemble the normal lining of the colon but look different under a microscope. They can become cancerous.