Unfortunately, doctors (and everyone else, for that matter) are notoriously inaccurate in predicting how long patients with terminal illnesses will survive. None of us has a crystal ball, and every individual is unique, even if they have the same stage and same cancer.
The above being said, it does appear that your mother-in-law has very advanced metastatic cancer, and that either her bile ducts are obstructed by cancer or her liver is starting to fail. Both of these events would be signs that the terminal phase of her metastatic cancer has very likely begun. Perhaps it is time, now, for her to consider hospice and palliative care options.
I wish that I could be of more help to you and your family.
Sincerely,
Robert A. Wascher, MD, FACS
www.doctorwascher.com
http://acancerpreventionguide.com