What is Pancreatic Cancer?

Types of Pancreatic Cancer

There are many types of pancreatic cancer, though they fall into two groups, based on the type of cell where they start. More than 90 percent of pancreatic cancers are exocrine tumors, arising from cells that produce pancreatic digestive juices, while the others are endocrine tumors and develop from cells that produce pancreatic hormones (such as insulin). Among the types:

Adenocarcinomas are by far the most common type of pancreatic cancer and usually develop in the ducts of the pancreas. These make up 95 percent of exocrine pancreas cancers.

Acinar cell carcinomas are exocrine tumors formed from the cells that make the digestive enzymes in the pancreas.

Intraductal papillary-mucinous neoplasm (IPMN) is an exocrine cystic tumor found in the pancreatic duct or branches from the duct. It may start as benign but could later become cancerous.

Neuroendocrine tumors (NET) arise from cells that secrete a variety of hormones and exhibit a spectrum of biologic behaviors from benign and indolent to frankly aggressive. These tumors can be functional and produce abnormally high amounts of hormones, or nonfunctional and not produce any hormones.  These include gastrinomas, glucagonomas, somatostatinomas and VIPomas.

Sarcomas, lymphomas and metastasis form other tumors  that can occur in the pancreas, but these are exceedingly rare. Other less frequent tumor types are possible, such as adenosquamous carcinomas, squamous cell carcinomas and signet ring cell carcinomas.

Pseudopapillary neoplasms are uncommon, slow-growing tumors that occur mostly in females in their teens and 20s.

Risk Factors

We still don’t know what causes pancreatic cancer, other than that it is related to changes in cellular DNA. It is unknown what triggers those changes. However, research points to various factors that increase your risk of developing pancreatic cancer. Some of these can be modified through diet and lifestyle changes, while others cannot. Risk factors include:

Smoking: Tobacco use is one of the strongest risk factors and may account for a quarter of all pancreatic cancers. Smokers are twice as likely to get it compared with people who have never smoked.

Advanced age: About two-thirds of patients are at least 65 years old.

Family history of pancreatic cancer: The disease runs in some families, though most people who get it do not have a family history of pancreatic cancer.

Inherited genetic disease: Certain genetic syndromes that are passed from parent to child are responsible for about 10 percent of cases. Among these are familial pancreatitis, Lynch syndrome, and hereditary breast and ovarian cancer syndrome.

Chronic pancreatitis: This chronic inflammation of the pancreas often is related to smoking and heavy alcohol use.

Diabetes: The risk, for unknown reasons, is higher for people with type 2 diabetes.

Obesity: People with a body mass index (BMI) of 30 or more are 20 percent more likely to develop the disease.

Symptoms

There often are no obvious symptoms until pancreatic cancer reaches advanced stages. Symptoms also may vary, based on the type of cancer and where it is found in the pancreas. As the disease progresses, symptoms may include:

• Abdominal pain that radiates toward your back
• Unexplained weight loss
• Itchy skin
• Loss of appetite
• Jaundice (yellowing of the skin or eyes)
• Dark-colored urine
• Light-colored stool
• General fatigue
• Diabetes diagnosis or new difficulties controlling existing diabetes
• Blood clots

Diagnosis

There are no effective screening tests available to look for pancreatic cancer in its early stages. There is hope, however, that clinical trials will provide one in the future. Currently, diagnosis typically begins when your doctor suspects that your symptoms may be related to pancreatic cancer. At that point, a series of tests will verify, or rule out, the diagnosis. Those include: