Colorectal cancer develops in the colon or rectum, parts of the large intestine. It is one of the most common cancers worldwide and is largely preventable with regular screening. Most cases begin as precancerous polyps that gradually become malignant.
Main types:
• Adenocarcinoma (most common)
• Rare types: carcinoid tumors, lymphomas, gastrointestinal stromal tumors (GISTs)
