Pancreatic Cancer

The pancreas is a gland in the digestive system. The pancreas secretes digestive enzymes into the first part of the small intestine, called the duodenum, to aid in the digestion of protein, fats, and carbohydrates. The pancreas also produces insulin and glucagon, which it secretes directly into the bloodstream to help regulate blood sugar.

The pancreas is made up of two types of cells:

  • Exocrine cells: These cells produce and deliver pancreatic enzymes used in digestion. The majority of cells in the pancreas are exocrine cells.
  • Endocrine cells: These cells exist in small clusters called islets and produce hormones — including insulin and glucagon — that are released directly into the blood and help regulate blood sugar.

Both exocrine cells and endocrine cells can form their own type of pancreatic cancer.

Types of Pancreatic Cancer

Exocrine pancreatic cancers and endocrine pancreatic cancers have different risk factors, causes, and symptoms and are diagnosed differently.

Exocrine Pancreatic Cancer
Exocrine pancreatic cancers are the most common pancreatic cancers, and nearly all exocrine cancers are pancreatic adenocarcinomas. Pancreatic adenocarcinomas usually form in the ducts of the pancreas but can also develop from cells that produce pancreatic enzymes (acinar cell carcinomas).

Endocrine Pancreatic Cancer
Tumors of the endocrine cells are less common. Often, they are called pancreatic neuroendocrine tumors (NETs) or islet cell tumors. About one-half of pancreatic NETs may produce excess hormones such as gastrinomas, insulinomas (often benign), glucagonomas, somatostatinomas, VIPomas, and PPomas.

Ampullary cancer, which starts where the bile duct and pancreatic duct come together (the ampulla of Vater), is not pancreatic cancer but is often treated the same way due to its location and similar behavior to pancreatic adenocarcinoma.