Bill Polk, MD: thoracic surgeon
Monday, August 15, 2011
TOPIC: Pancreatic Cancer
David McMillen, MD: gastroenterologist
news notes via www.webmd.com
Pancreatic Cancer Overview
Each year, about 37,000 people in the U.S. are diagnosed with pancreatic cancer. About one in 76 people in the U.S. will develop the disease. Pancreatic cancer affects about equal numbers of men and women, almost always after the age of 45.
Cancer of the pancreas barely makes the top 10 most common cancers in the U.S. However, pancreatic cancer's tendency to spread silently before diagnosis makes it the fourth deadliest cancer diagnosis.
Types of Pancreatic Cancer
Pancreatic cancer is classified according to which part of the pancreas is affected: the part that makes digestive secretions (exocrine) or the part that makes insulin and other hormones (endocrine).
Exocrine Pancreatic Cancer
Although there are several different types of pancreatic cancer, 95% of cases are due to pancreatic adenocarcinoma.
Other less common exocrine pancreatic cancers include:
The exocrine pancreas makes up 95% of the pancreas, so it's not surprising that most pancreatic cancers arise here.
Endocrine Pancreatic Cancer
Other cells of the pancreas make hormones that are released directly into the bloodstream (endocrine system). Cancer arising from one of these cells is called neuroendocrine pancreatic cancer or islet cell pancreatic cancer.
Endocrine pancreatic cancers are quite rare, and are named according to what kind of hormone-producing cell it starts from:
Endocrine tumors usually are not cancer at all; they are nonmalignant growths. These "benign" tumors are not considered pancreatic cancer. However, they may grow to a large size or secrete unhealthy quantities of hormones, causing medical problems.
Ampullary Cancer (Carcinoma of the Ampulla of Vater)
Cancer can develop where the tube (duct) that drains the pancreas enters the small intestine (an opening called the ampulla). Although it's not technically pancreatic cancer, ampullary cancer causes symptoms similar to pancreatic cancer, and is treated similarly.
Causes of Pancreatic Cancer
Pancreatic cancer occurs when cells in the pancreas grow, divide, and spread uncontrollably, forming a malignant tumor. The exact cause of pancreatic cancer is unknown.
Age, male gender, and family history are other risk factors for pancreatic cancer.
Prevention of Pancreatic Cancer
There is no known way to prevent pancreatic cancer. Not smoking, keeping a healthy weight, and eating a plant-based diet should reduce your risk for pancreatic cancer.
Diagnosis of Pancreatic Cancer
In addition to a history and physical exam, imaging tests may be performed to help make the diagnosis of pancreatic cancer. These tests include:
A definitive diagnosis of pancreatic cancer only comes from removal of cancer tissue (biopsy). This can be done with a needle through the skin, during endoscopy, or with an operation.
Treatment for Pancreatic Cancer
Pancreatic cancer is treated in several ways, alone or in combination:
Surgery is generally done to attempt to cure pancreatic cancer, but it may also be done to lessen or prevent symptoms. Chemotherapy and radiation are often given together, with or without surgery, to slow pancreatic cancer's growth. Palliative care aims to reduce discomfort for people whose pancreatic cancer cannot be cured.
What to Expect From Pancreatic Cancer
Pancreatic cancer is a serious condition. Most cases of pancreatic cancer have already spread at the time of diagnosis, making a full cure unlikely. Treatments can allow people to live longer with pancreatic cancer, and help them feel better. Clinical trials are ongoing to discover more effective ways of treating pancreatic cancer.
Pancreatic Cancer Symptoms
Pancreatic cancer often goes undetected until it's advanced and difficult to treat. In the vast majority of cases, symptoms only develop after pancreatic cancer has grown and begun to spread. What are the symptoms of pancreatic cancer, and can any symptoms lead to earlier detection?
Because more than 95% of pancreatic cancer is the adenocarcinoma type, we'll describe those symptoms first, followed by symptoms of rare forms of pancreatic cancer.
Pancreatic Cancer Symptoms: Location Matters
Initially, pancreatic cancer tends to be silent and painless as it grows. By the time it's large enough to cause symptoms, pancreatic cancer has generally grown outside the pancreas. At this point, symptoms depend on the cancer's location within the pancreas:
In general, symptoms appear earlier from pancreatic cancers in the head of the pancreas, compared to those in the body and tail.
Pancreatic Cancer: Gastrointestinal Symptoms
Because pancreatic cancer grows around important areas of the digestive system, gastrointestinal symptoms often predominate:
Pancreatic Cancer: Constitutional (Whole-Body) Symptoms
As it grows and spreads, pancreatic cancer affects the whole body. Constitutional symptoms can include:
Pancreatic Cancer: Skin Symptoms
Jaundice: As pancreatic cancer blocks the duct that releases bile into the intestine (common bile duct), the ingredients of bile build up in the blood. This turns the skin and the eyes yellow, a condition called jaundice.
Itching: People with pancreatic cancer sometimes report itching all over. Blockage of the bile ducts is often responsible.
Pancreatic Cancer's Sneaky Symptoms
In a very small number of people with pancreatic cancer, early symptoms might be present that could lead to earlier diagnosis. Unfortunately, researchers have been unable to identify any predictable pattern. One study that surveyed 305 people with pancreatic cancer illustrated the challenge:
The rarity of these situations points out the difficulty of using early symptoms to catch pancreatic cancer at a curable stage.
That said, symptoms like weight loss, persistent loss of appetite, or light-colored stools should always prompt concern. Consistent or worsening discomfort, nausea, vomiting, or diarrhea are also worrisome. If you feel something's not right, see your doctor.
Pancreatic Cancer Treatments by Stage
The best treatment for pancreatic cancer depends on how far it has spread, or its stage. The stages of pancreatic cancer are easy to understand. What's harder is determining the stage without resorting to major surgery. In practice, doctors choose pancreatic cancer treatments based on imaging studies and a person's individual factors.
Stages of Pancreatic Cancer
Stage is a term used in cancer treatment to describe the extent of spread. The stages of pancreatic cancer exist partly to guide treatment, but also to classify patients for clinical trials. The stages of pancreatic cancer are:
Determining pancreatic cancer's stage is often tricky. Imaging tests like CT scans and MRIs provide some information, but knowing exactly how far pancreatic cancer has spread usually requires surgery.
Since surgery has risks, doctors first determine whether pancreatic cancer appears to be removable by surgery (resectable). Pancreatic cancer is then described as follows:
If pancreatic cancer is resectable, surgery could extend life and offer a small chance of cure.