Intestinal Tumors and Carcinomas:
Intestinal tumors are said to be linked to several different risk factors, which can cause different forms of intestinal tumors. Risk factors to be aware of are:
Polyps within the intestine
Though having one of the four risk factors does not necessarily mean you will develop intestinal cancer, nor will not having one of these risk factors mean that you cannot develop intestinal cancer, if you ever feel concerned, contact your family physician or gastroenterologist.
There are four different types of tumors all with different classifications:
- Gastrointestinal Carcinoid tumors
If you have small bowel resected from a procedure to remove an intestinal tumor, there is a risk of developing SBS if a significant amount of bowel is removed.
Adenocarcinomas make up about 30% to 40% of small intestine cancers. This type of cancer starts from the cells that line the intestine. Most experts think that cancer of the small intestine develops much like colorectal cancer. It first begins as a small benign outgrowth called a polyp. Over time, the polyp can change into a cancer. Most small intestinal cancers develop in the duodenum with the rest occurring in the jejunum and ileum.
A major site of cancer in the duodenum is the ampulla of Vater. But because this area is closely associated with the pancreas, it is treated like pancreatic cancer.
Gastrointestinal Carcinoid Tumors
GI Carcinoid tumors start from cells of the diffuse neuroendocrine system. This system consists of cells that are like nerve cells in certain ways and like hormone-making endocrine cells in other ways. These cells do not form an actual organ like the adrenal or thyroid glands. Instead, they are scattered throughout other organs like the esophagus, stomach, pancreas, intestines, and lungs. The digestive system is large and contains more neuroendocrine cells than any other part of the body. This may explain why carcinoid tumors most often start in the digestive system.
Neuroendocrine cells help control the release of digestive juices and how fast food moves in the GI tract. They may also help control the growth of other types of digestive system cells.
Like most cells in the body, GI tract neuroendocrine cells sometimes go through certain changes that cause them to grow too much and form tumors. These tumors are known as neuroendocrine tumors (NET) and neuroendocrine cancers. In the past, most abnormal growths of neuroendocrine cells were called carcinoids. But in 2000, the World Health Organization (WHO) reclassified carcinoids into neuroendocrine tumors and neuroendocrine cancers.
Neuroendocrine tumors are growths that look benign but that might possibly be able to spread to other parts of the body. Neuroendocrine cancers are abnormal growths of neuroendocrine cells which can spread to other parts of the body.
Neuroendocrine cancers (also known as neuroendocrine carcinomas) can then be divided into groups based on the way the cells look under the microscope. A cancer with cells that do not look very abnormal is called well differentiated. These tumors tend to be less aggressive. They grow and spread slowly. Well differentiated neuroendocrine cancers can look identical to benign neuroendocrine tumors when examined under the microscope. Sometimes the only way to know for certain that a mass is a neuroendocrine cancer (and not a benign tumor) is when it spreads to other organs or tissues. If the cells of a cancer look very abnormal, it is called poorly differentiated. These cancers tend to be more aggressive meaning that they grow and spread quickly.
Lymphomas of the small bowel may be primary (i.e. arising from the small bowel lymph tissue) or secondary to a systemic lymphoma. The small bowel is composed of the duodenum, jejenum, and ileum. Lymphomas can affect any one of these intestinal sections, or the colon.
This fairly uncommon cancer is typically a non-Hodgkin’s type that starts in the lymph tissue of the small intestine. (The body’s immune system is comprised of lymph tissue, which assists in fighting infections.) Malignant lymphoma is not often found as a solitary lesion.
For more information on General Lymphomas see the following link from the American Cancer Society.
Sarcoma malignancies of the small intestine are usually leiomyosarcoma. They most often occur in the smooth muscle lining of the ileum, the last section of the small intestine. Liposarcoma and angiosarcoma occur more rarely in the small intestine.
Children’s Hospital of Pittsburgh: Intestinal Diseases
American Cancer Society