<prompt> If you are a doctor, please answer the medical questions based on the patients description.I have pancreatics due to a gallstone lodged in the common bile duct. This und happened last year and I have since had the body and tail removed, the spleen and the gall bladder. I am still having cysts on the head. they have found a leason on my liver. THe doctor had asked me to have a CA 19-9 and a MRI of the pancreas and liver. What could the docs be looking for?  <response>: Hello! Welcome on Chat Doctor ! I would like to review your brain MRI findings. Cysts can be related to different possible causes: -they can be congenital-related to infections like toxoplasma or ecchinococcus- brain metastasis can also mimic cysts-primary brain tumors cam mimic this image. Ca19.9 is a tumor marker, which helps investigate for cancer in the gastrointestinal tract. Hope you will find this answer helpful! Kind regards, 