When is a liver transplant necessary for liver cancer?

In response to a question on healthshare.com.au

Liver transplantation is one of the treatments that can be effective for hepatocellular carcinoma (HCC), also called primary liver-cell cancer or sometimes called hepatoma.

Transplantation is more effective when the cancer does not involve the blood vessels supplying the liver; when the cancer does not extend beyond the liver; and when the total bulk of liver cancer is not excessive. However, these same factors also make other treatments more effective. See: http://www.healthshare.com.au/questions/44099-what-is-the-treatment-for-liver-cancer

Liver transplantation is usually used when the cancer is considered curable by surgical removal, but when the amount of liver that would have to be removed would make surviving the operation risky or impossible. This can be due to the position of the cancer - for example, if it is close to the major blood vessels entering or leaving the liver - or if the “future liver remnant”, the bit of liver remaining after surgery, is too small to support the body's vital functions.