With my experience, you may contact a very expert Dr. Gangadaran who working in Indian Hospital. Lakshore Hospital, Kerala (Dr. Mobile Number.+91-9847064668)
Then discuss with him for further step. OP time his mobile may be switched off, but you keep try even night he will respond. With my personnel experience, he is a very expert for cancer treatment. During my last week visit I found many foreigners are visiting him for cancer treatment. God bless your father.