pancreas cancer : Types of Tumors of the Pancreas

The pancreas is a gland found behind the stomach. It is shaped a little bit like a fish. It is about 6 inches long and less than 2 inches wide. It extends across the abdomen.

The pancreas is really 2 separate glands inside the same organ. The exocrine gland makes pancreatic juice that has enzymes to break down fats and proteins in foods so the body can use them. Most of the cells in the pancreas are part of the exocrine system. A smaller number of cells in the pancreas are endocrine cells. These cells are arranged in clusters called islets (or islets of Langerhans). They make hormones (such as insulin) that help balance the amount of sugar in the blood.

Types of Tumors of the Pancreas

Both the exocrine and endocrine cells of the pancreas can form tumors. But those formed by the exocrine pancreas are much more common. Not all of these tumors are cancer. A small number of tumors are benign (not cancer).

It is important to know whether a tumor is from the exocrine or endocrine part of the gland. Each type of tumor has distinct signs and symptoms, is found using different tests, is treated in different ways, and has a different outlook for survival (prognosis).

Tumors of the exocrine part of the gland are likely to be cancer. These cancers are called adenocarcinomas. About two thirds of these cancers are found in the head of the pancreas; the rest are in the tail. There are several sub-types. But treatment of cancer of the exocrine pancreas is mostly based on the stage of the cancer, not its exact type. The stage of the cancer describes how far it has progressed. Staging is explained later in this document.

Tumors of the endocrine pancreas are much less common. They are known as islet cell tumors. There are also several sub-types. Most of these are benign, but there are a few that are cancerous. This overview does not cover islet cell cancers.

A special type of cancer (ampullary cancer) can occur where the bile duct (from the liver) and the pancreatic duct empty into the small intestine. Because this type of cancer often causes signs such as yellowing of the skin and eyes, it is usually found at an earlier stage than most pancreatic cancers. Finding it early means that the chances of successful treatment are better.

Copyright 2006 © American Cancer Society, Inc.