Dear Dr. Roach: Are you aware of the possibility of pancreatitis resulting from long-term vitamin D2 supplementation? I was diagnosed with IPMN with chronic pancreatitis after being on 50,000 IU of vitamin D2 once a week for nine months. I had mild upper left quadrant pain, which I am told is quite unusual for pancreatic cysts. After doing some research, I decided to decrease and then stop the D2. As I did, cyst sizes and tumor markers both decreased. In addition, the pain resolved. I was fortunate enough to detect the connection, but have not had any interest from medical practitioners about looking into the possible link here. J.D.
Answer: This is a complex issue, and it starts with your IPMN, which stands for intraductal papillary mucinous neoplasms of the pancreas. These are tumors of the pancreas that are at risk for becoming cancerous.
The size is the biggest predictor of malignancy, so your doctors are likely monitoring the size of your tumors. Those less than 2 cm in size are at low risk for malignancy. Malignant and cancerous are synonymous terms, but the boundary between benign tumors and malignant ones is not as sharp a line as we used to think.
These cystic tumors are filled with mucin and can block the main pancreatic duct or a side pancreatic duct, through which the pancreatic enzymes that help to digest food flow into the small intestine. Insulin is also produced by the pancreas, but it is transported to the body through the splenic vein into the liver rather than the ducts into the intestine. Blockage of the ducts causes ductal dilation behind the obstruction. For the subset in whom the pancreatic ducts get blocked, IPMN can also cause inflammation of the pancreas, called pancreatitis.
Scientists observed that vitamin D levels D2 and D3, the usual kind we supplement are low in people with any kind of pancreatitis, but vitamin D treatment often made the pancreatitis worse. This seeming paradox was resolved when it was further found that the inflammatory cells in the inflamed pancreas were making the active form of vitamin D (1,25-dihydroxy vitamin D), and high levels of this active D vitamin were increasing calcium levels. The increase made pancreatitis worse. The low levels of circulating vitamin D2 and D3 are part of the bodys response to the elevated 1,25-dihydroxy vitamin D. Vitamin D supplementation is thus not usually done in pancreatitis since it can make it worse.
With the lessening of inflammation because you stopped the D2, its possible the cysts decreased in size and the ducts were able to go back toward normal, relieving inflammation in your case of IPMN.
