The pancreas – which lies behind the stomach – contains two different types of glands, exocrine and endocrine. Pancreatic cancer can arise in either gland. However, the symptoms, diagnosis, treatment, and prognosis is different for each type of pancreatic cancer.
The exocrine glands release enzymes into the intestines that help digest fats, proteins, and carbohydrates. Exocrine tumors are by far the most common type of pancreatic cancer. Less common types of cancer in this area of the pancreas are adenosquamous carcinomas, squamous cell carcinomas, giant cell carcinomas, and ampullary cancers.
The endocrine glands contain the blood sugar-regulating hormones insulin and glucagon. Endocrine tumors (also called pancreatic neuroendocrine tumors or NETs) are uncommon. Treatment and prognosis depend on the specific tumor type and stage. Generally, the prognosis for endocrine cancers is better than that of exocrine cancers.
Unfortunately, the incidence of pancreatic cancer has been slowly increasing over the past 15 years.
Cigarette smoking is thought to cause up to 20 to 30 percent of pancreatic cancers. Obesity is a risk factor, as is heavy exposure to certain pesticides, dyes, and chemicals used in metal refining. People with a long-term inflammation of the pancreas (chronic pancreatitis) are at higher risk. In addition, people who have cirrhosis of the liver and certain inherited disorders or genetic syndromes, are also at risk. Alcohol may have an indirect link as it raises the risk for diabetes, cirrhosis, and chronic pancreatitis.
Pancreatic cancer rarely occurs in people younger than 45; the average age at the time of diagnosis is 72. Men are slightly more likely to develop pancreatic cancer than women.
Very few pancreatic cancers are found early because of the location of the pancreas, deep inside the body. Patients usually do not have symptoms until the cancer has metastasized to other organs. There are currently no blood tests to detect pancreatic cancer, but doctors are experimenting with a procedure called an endoscopic ultrasound that might be useful in screening high risk individuals.
The symptoms of exocrine pancreatic cancers and endocrine pancreatic cancers are different. Exocrine pancreatic cancer symptoms include: jaundice, darkened urine and/or lighter stools, pain in the abdomen or back, unexplained weight loss and poor appetite, digestive problems, gallbladder enlargement and blood clots. These symptoms are most often signs of something other than cancer, but should be checked out by a doctor.
Most symptoms of NETs (endocrine cancers) are caused by the excess hormones released into the bloodstream by the tumor; each type of tumor has unique symptoms depending on which hormone is involved. Symptoms can range from stomach ulcers, diarrhea and digestive problems to anemia, jaundice, skin rash, low blood sugar and many other problems. Even NETs that don't release hormones can spread, interfering with the normal function of the area where they settle.
Exocrine pancreatic cancer is treated with surgery, radiation, and chemotherapy. Depending on the stage of the cancer, some of these treatments may be combined. Endocrine pancreatic cancer can be treated with surgery, radiation, chemotherapy, and with specific drugs to address particular hormones. Pancreatic cancer surgery is a very complex and difficult operation with varying degrees of success.