The pancreas makes enzymes from a type of cell called an exocrine cell. Most of your pancreas is made up of exocrine cells.
A very small part of the pancreas is made of endocrine cells. These cells make hormones, such as insulin.
Pancreatic tumors start in either exocrine or endocrine cells. More than 9 out of 10 pancreatic cancers are exocrine tumors, not neuroendocrine tumors.
There are about 20 different types of tumors can grow in the pancreas.
These tumors often start in the pancreas ducts, which are small channels that carry digestive enzymes to the intestines.
Adenocarcinoma (A-deh-noh-KAR-sih-NOH-muh): This is the most common kind of exocrine pancreatic cancer. Also called ductal carcinoma, it starts in the lining of pancreas ducts.
Acinar cell carcinoma (ACC): This type of adenocarcinoma starts in exocrine cells and is a very rare cancer.
Adenosquamous carcinoma (A-deh-noh-SKWAY-mus KAR-sih-NOH-muh): This rare exocrine pancreatic cancer is hard to diagnose. It’s made of squamous cell carcinoma and ductal adenocarcinoma. This tumor can be more aggressive than adenocarcinoma.
Pancreatoblastoma: This tumor is very rare. It affects young children and grows slowly.
Squamous cell carcinoma: This tumor is mostly made of squamous cells. It’s very rare and hard to treat, because the cancer is found after it has spread.
Solid pseudopapillary tumor (SPT) or Solid pseudopapillary neoplasm (SPN): Very rare, they make up only about 1 out of every 100 pancreatic tumors. SPT and SPN mostly affect young women and are easier to treat than other pancreatic cancers.
Pancreatic neuroendocrine tumors are also known as islet cell tumors or islet cell carcinoma. They’re a type of neuroendocrine tumor found in the pancreas.
Pancreatic cysts are growths filled with fluid that start in the pancreas. Most pancreatic cysts are benign (not cancer). They’re not likely to harm you or cause symptoms. But some are precancerous and can turn into pancreatic cancer.
Serous cystadenoma: This is a type of cystic neoplasm, or cysts filled with fluid. It’s made of serous cells. Most serous cystadenomas do not become cancer.
Intraductal papillary mucinous neoplasm (IPMN): This is a cyst that can become cancer. It starts in the ducts that connect the pancreas to the intestine. They’re the most common type of precancerous cyst. They make large amounts of proteins that form mucus (mucin) in the cyst lining and fluid.
Mucinous cystic neoplasm (MCNs) are precancerous growths that start in the body and tail of the pancreas. They almost always affect women. Large MCNs that have tiny walls divide the cyst into compartments, called septations. They may be more likely to become cancer.