Colon cancer forms from polyps, which are small growths located on the inside of the colon. Polyps, and subsequent cancers, form when cells accumulate an increasing number of genetic mutations that allow them to grow uncontrollably.
Polyps are located in the most superficial layer of the colon wall. As they grow, they form tumors and can become invasive, meaning they can invade deeper into the colon wall and even spread outside of the colon to the lymph nodes or through the bloodstream to various organs.
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