Adenocarcinoma is the name of a broad category of cancers. This type of cancer occurs in cells that line organs such as the colon, lung, and breast.

What is going on in the body?

Structures within the body are covered with layers of tissue. One of these layers of tissue is called the epithelium. It covers the inside of hollow organs and milk ducts in the breast. When cancer occurs in one of the cells of the epithelium, it is called an adenocarcinoma. The cancer is also categorized by the kind of tissue from which it arose, such as breast or lung.

Cancer occurs when a cell undergoes changes that make it grow and multiply uncontrollably. The abnormal cells grow into a mass, which is called a tumor. Cancer cells from the tumor can break off and metastasize. This means that they spread to other parts of the body. New tumors may then form. In addition to spreading, adenocarcinoma also destroys the tissue around it.

What are the causes and risks of the disease?

Smoking increases the risk for almost every kind of cancer. There may be other risk factors for adenocarcinomas in different organ sites. Each site may have different factors. For example, hormone replacement therapy may increase the risk of uterine adenocarcinoma. Colon adenocarcinoma may be related to a diet high in fat or low in fiber. In the same way, the risk for adenocarcinoma of the small intestine increases with a history of Crohn disease.