When “Jeopardy” host Alex Trebek announced in early March that he had stage 4 pancreatic cancer, the disease hit the public’s radar, triggering the usual mix of garbled information and fear. So, just what is the pancreas, and who is at risk of developing pancreatic cancer?
The pancreas is a gland that sits behind the stomach and produces hormones that regulate blood sugar and digestive enzymes. When the cells that make up the pancreas grow in an uncontrolled manner, this can develop into pancreatic cancer.
Rare but DeadlyUnfortunately, pancreatic cancer is on the rise. By some estimates, as soon as next year it may become the second leading cause of cancer death in the U.S., after lung cancer. However, the disease is still relatively rare: 56,770 new cases are expected in 2019, accounting for approximately 3 percent of all cancers. In comparison, 271,270 new breast cancers, 228,150 new lung and bronchus cancers, and 145,600 new colorectal cancers are expected in 2019.
But the problem is that the symptoms of pancreatic cancer, which include weight loss, dark urine and abdominal pain, do not usually appear until the later stages, making it quite difficult to treat. Eighty percent of all cases are diagnosed at an advanced stage, and at that point there is only approximately an eight percent chance of surviving for another five years.
Risk Factors The main risk factors for pancreatic cancer include older age, tobacco use, heavy alcohol use, and obesity. Approximately 10 percent of pancreatic cancers appear to be hereditary and run in families. Importantly, people at the highest risk may be candidates for pancreatic cancer screening.
Those considered to be at high risk include people who have two or more close blood relatives affected by pancreatic cancer (what’s known as a significant family history), and people who carry certain inherited genetic mutations associated with the disease. (Some folks fit in both of those categories.)
Several genes have been linked with an increased risk of developing pancreatic cancer. These include the BRCA1 and BRCA2 genes, well known for their association with breast and ovarian cancer, and the so-called mismatch repair genes that cause Lynch syndrome, a condition better known for its association with colon and endometrial cancers.
Mutations in BRCA1 and BRCA2 can be found in up to 2.5 percent of those of Ashkenazi Jewish ancestry. Therefore, typically, when a patient comes to my office, I first take a family history going back three generations to identify cancers in the family (and the age of onset) to see if there is a suggestion of a hereditary cancer syndrome in the family. We then make a joint decision on whether to do genetic testing, and whether other family members should also consider such testing.
Screening Options Once we have information about genetic risk, we can talk about whether someone is a candidate for pancreatic cancer screening. Even without doing genetic testing, some people with multiple affected family members (such as a mother and maternal grandfather) may be candidates for screenings. Current consensus-based guidelines suggest that those at the highest risk may consider annual screening, with either magnetic resonance imaging (MRI) or endoscopic ultrasound (EUS).
DNA testing also has the potential to help patients with pancreatic cancer. Recent studies have found that from 4 to 20 percent of pancreatic cancer patients carry mutations that can be passed down to other generations. Identifying these mutations can help patients fight pancreatic cancer, because they might respond differently to certain chemotherapy protocols and other targeted treatment therapies that are now being used for some of the BRCA1/2 mutation carriers, as well as Lynch syndrome patients. It can also provide critical information to a patient’s family members who are considering genetic testing and/or screening for other cancers.
Possible Diabetes Connection?Some new research suggests that diabetes, including type 2, may also be a risk factor for, and a consequence of, pancreatic cancer. A recent study from the Mayo Clinic found that some pancreatic cancer patients had elevated fasting blood sugar levels, a marker of diabetes, three years prior to their cancer diagnosis. Researchers are now interested in whether a new diagnosis of diabetes should trigger a workup for pancreatic cancer. That said, the vast majority of cases of type 2 diabetes, which is on the rise in the U.S., are not related to pancreatic cancer; more studies are needed to determine which newly diagnosed diabetes patients should be evaluated for the disease.
If you think you may be at increased risk for pancreatic cancer, be it a family disease or the recent onset of diabetes, be sure to keep an eye open for these symptoms:
• Jaundice (yellowing of the eyes and skin)
• Abdominal pain
• Dark urine
• Light-colored stools
• Weight loss
If you have any of these symptoms, please speak with your doctor. If you are concerned about your risk factors, especially if there is a family history of pancreatic cancer, don’t hesitate to ask us about genetic testing and whether you may be a candidate for pancreatic screening.
Aimee Lucas, MD, MS is an associate professor of medicine in the Division of Gastroenterology at The Mount Sinai Hospital