Editor’s note: In honor of World Diabetes Day, we recently spoke with Suresh Chari, MD, about the connection between diabetes and pancreatic cancer. Chari is a professor of medicine and consultant in the division of gastroenterology and hepatology at Mayo Clinic and a member of the Pancreatic Cancer Action Network’s (PanCAN’s) Scientific and Medical Advisory Board (SMAB). He was instrumental in the discovery that new-onset diabetes can be an early symptom of pancreatic cancer. Here are six important things to know about diabetes and pancreatic cancer, according to Chari:
- Long-standing diabetes is a (modest) risk factor for pancreatic cancer.
Long-standing diabetes can be considered a risk factor for pancreatic cancer. It causes a modest increase in risk of 1.5- to two-fold. Some of the other risk factors for pancreatic cancer include smoking, chronic pancreatitis (inflammation of the pancreas), family history of pancreatic cancer, obesity and certain genetic syndromes.
- The duration of diabetes matters.
Individuals who’ve had diabetes for more than five years can be considered at a slightly higher than average risk of developing pancreatic cancer, as noted above. But those with new onset of diabetes after age 50 have a nearly 1 percent chance of being diagnosed with pancreatic cancer within one to three years following their diabetes diagnosis. In this case, the pancreatic tumor caused the diabetes.
- Diabetes is also a symptom of pancreatic cancer.
It’s thought that pancreatic cancer can cause cells in the body to become resistant to insulin, a key hormone produced by the pancreas, that helps regulate blood sugar levels. In other insulin-resistant conditions (like obesity), the insulin-producing cells in the pancreas produce more insulin to overcome the insulin resistance. But pancreatic cancer appears to impede the insulin-producing cells of the pancreas from responding adequately to this insulin resistance. This results in development of diabetes. It’s important to note that even though pancreatic neuroendocrine tumors (PNETs) arise from the hormone-producing cells of the pancreas, diabetes is neither a symptom nor risk factor for PNETs.
- Diabetes that arises because of a pancreatic tumor is different. The biology and clinical presentation of new-onset diabetes that is caused by pancreatic cancer is different from the more common adult-onset diabetes, type 2. Type 3c diabetes is defined as being caused by disorders in the pancreas, such as malignant disease. Strikingly, patients with type 3c diabetes due to pancreatic cancer experience weight loss, instead of weight gain seen in type 2 diabetes, a symptom that is often overlooked by physicians.
- New-onset diabetes can be an early indicator of pancreatic cancer. If diagnosed correctly, new-onset type 3c diabetes can signal that something is awry in someone’s pancreas. Other researchers and we have been looking at this relationship for quite some time. And PanCAN recently awarded targeted grants and is working on key projects to discover clues to help detect pancreatic cancer sooner in people with new-onset diabetes.
- Both diabetes and pancreatic cancer could dramatically benefit from earlier detection. It’s very appropriate that World Diabetes Day and World Pancreatic Cancer Day happen within a few days of one another. Both ailments can present with vague symptoms that can be dismissed by both doctors and patients, and both can be much more manageable if diagnosed early and accurately. PanCAN’s focus on Demand Better this November means that we need to demand earlier detection of pancreatic cancer. We as researchers and clinicians need to ask more of ourselves to achieve that goal. Early detection is possible and will make a difference!
Chari visited the PanCAN office earlier this month, and we filmed a Facebook Live video of him speaking about the relationship between pancreatic cancer and diabetes, and efforts toward pancreatic cancer earlier detection.