5. Diarrhea and greasy stools
The pancreatic juice has an important role in digesting protein, carbohydrates and fat. Thus, an impaired function of the pancreatic juice would cause various digestive problems, including problems to absorb fatty acids. This problem becomes even worse when the pancreatic tumor causes an alteration to the secretion of bile as well. In either case, it is possible to experience greasy stools as a sign of pancreatic cancer, and certain types of cancer would also cause persistent and profuse diarrhea.
There are specialized cells in the pancreas that synthesize and secrete a substance called vasoactive intestinal peptide. When pancreatic cancer takes these cells, they start secreting this substance without any control, similar to what happens in insulinoma. Vasoactive intestinal peptide reaches the intestines and regulates the calibre of the blood vessels. An increase in this substance will dilate the blood vessels in the intestines and make them more permeable, allowing water to leak out into the intestinal lumen. More water in the intestines would overcome the reabsorbing capacity of the colon, and lead to watery stools and chronic diarrhea.