[michaelochurch]

Cancer can kill quickly but doctors rarely give specific timelines, at least in the US. "30 days" seems suspicious, if only because most doctors hate giving specific amounts of time. (If the person lives half as long, then the family gets angry because they thought there was more time. If the person lives much longer-- sometimes an order of magnitude more, given the complexities of misdiagnosis, new treatments, etc.-- then there's a different kind of blowback.)

I would guess that it's metastatic cancer. Mentioning the liver is an indication. Once the liver's involved, cancer gets very hard to treat. Typical chemotherapy is killing the cancer by flooding the body with poison, and doing that when the liver's compromised is often fruitless (and painful).

Most likely, the doctors have stopped treatment, in which case 30 days is a reasonable median, but he'll be essentially functional until the last 2 weeks. However, there are cases (although they're quite rare) of people living for months or even years after that happens. Spontaneous remission is uncommon (less than 1%) but it does occur. That's yet another reason why doctors don't like giving specific timelines.