Thanks for your question on Health Care Magic.
I can understand your concern.
Since doctors are telling that his liver cancer
is inoperable, he is having mostly end stage (stage 4) cancer.
Treatment options are only palliative therapy.
Palliative therapy includes, palliative chemotherapy
, radiotherapy, nutritional support and pain management.
So consult good oncologist
and start appropriate treatment.
Hope I have solved your query.
I will be happy to help you further.
Wishing good health to your father in law.