I am very confused. My sister in law has stage 4 pancreatic cancer, it has spread to her liver, lungs and spleen. She is having pallative chemo. However, the doctor said her cancer has shrunk! But, I got a phone call from her today and she had the worse pain ever in her back. She took extra morphine (something she never does so it must have been bad). How can she be in so much pain if it is shrinking?