it all depends on the size of the mass. If it's small (less than 5 or 6cm depending on the hospital & country) then there are multiple treatment options, including burning the mass ("radiofrequency ablation"), chemotherapy
plus burning ("TACE"), liver transplantation
, and liver resection (if he is has no cirrhosis
If the mass if larger, then treatment is limited. TACE can be done and local chemotherapy beads can be placed in the tumor. Pills of chemotherapy can be given to help increase survival (it's called sorafenib
Ask your liver doctor to make sure this is an hepatocellular carcinoma
(this will be suggested by the CT scan, his history of cirrhosis or not, some special blood tests, and finally sometimes a biopsy is needed).
Hope that helps.