The mysterious pancreas

The shape and existence of the pancreas has been known since antiquity.  The Greek surgeon Herophilus, one of the founders of the medical school of Alexandria, described the pancreas about 300 BC.  He was the first to perform systematic dissections of human cadavers (and live vivisections of prisoners.)  He wrote several books, but they are lost.  His work on anatomy is known only through the books of later surgeons.

The pancreas is a fairly large organ located in the interior of the abdomen.  It lies behind the stomach and in front of the spine. The head of the pancreas is surrounded by a section of the small intestines.

While the physical description of the pancreas has been known for thousands of years, its function has not.  Its location, deep within the abdominal cavity, made it one of the last organs to be studied in detail.  Even today, pancreatic cancers are difficult to diagnose early because they remain hidden inside the abdomen. As late as the 1880’s it was generally thought that the pancreas had no essential function, like the appendix.

Johann Conrad Brunner, a Swiss anatomist, was a professor at the University of Heidelberg in the late 1600s.  He showed that a large portion of the pancreas could be removed from an animal without affecting the animal’s health.  This result stood for over two hundred years and was often misinterpreted so that it was thought the entire pancreas could be removed without affecting the animal’s health, like the appendix. A total pancreatectomy, complete removal of the pancreas, was a difficult procedure to perform. If the surgeon missed a small portion of the pancreas, the animal could function adequately with only that small portion.

As late as 1888, Giovanni Marinotti described what he thought to be the complete removal of a dog’s pancreas. Consistent with Brunner’s conclusions, Marinotti found that this caused no change in the dog’s general condition or its digestive functions.