First, I'm very sorry to hear you've been diagnosed. From what I've learned, how long you live with secondary liver cancer depends on where the cancer started and how far
it has progressed.
One of the things I was interested to find out is that secondary liver cancer acts like its origin. (Secondary liver cancer is cancer that starts elsewhere and spreads to the liver.) So if the cancer started in your colon, it will act like colon cancer, not liver cancer.
There are tests that your doctor will do to help figure out your prognosis for secondary liver cancer. These can test your tumor's resistance to drug treatment, tell about tissue function, and identify the stage of the disease.
Best wishes for a good prognosis.