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.
While the exact causes of prostate cancer are not known, certain risk factors have been linked to prostate cancer. A risk factor is something that increases a person's chance of getting a disease. Aging is the greatest risk factor for prostate cancer. Family history also plays a role.