Stage 4 sarcomatoid carcinoma, 50 tumors in liver, what are best options for treatment?

Sometime in late September to early October of 2016, my father (56 year-old caucasian male; was 202 lbs in October, is currently 193 lbs) noticed a bump on his face directly in front of his ear that was hard and painful when touched. He told his ENT and he ordered a CAT scan and a biopsy. By the time we got the results of the tests several more bumps had appeared in the same area along with a larger lump on the same side of his neck. The results indicated cancer in his parotid gland and surrounding lymph nodes. In mid December, a surgeon removed the parotid gland and 23 lymph nodes from his neck and the side of his face (sacrificing a large branch of the facial nerve in the process). After coming home a little bit less than a week after the surgery, my father found that he was becoming more and more tired and out of breath even when exerting very little energy. This past Saturday, we took him to the emergency room because our family doctor was worried that he might have a blood clot. Instead, they found that his bilirubin was building up in his system (also causing his stool to be yellowish) and his liver enzymes were (and still are) rapidly increasing. He had a PET scan yesterday and the results came back earlier today. The scan revealed over 50 tumors in his liver and over 20 in his spleen. This is when we were told that he has stage 4 sarcomatoid carcinoma. The preferred treatments for this (I believe the nurse practitioner told us they were taxanes and a some form of chemotherapy that is very toxic to the liver and kidneys) are not options because the cancer is in his liver and because he has had two kidney transplants (a double transplant in 1992 and one kidney transplant in 2012). His current symptoms are shortness of breath, fatigue, yellow stool, and pain in the left upper quadrant. What I want to know is what our best options will be for treatment. I also want to know the survival rate for this form of cancer and how long he may have to live.