[ElaineM]

Some medicines (cancer and other medicines) can cause a rise in the liver enzymes (ALT and AST), but it is always best to get it checked out by doing various tests, like cat scans, or pet scans or ultrasounds of the abdomen. There could also be a problem with the liver unrelated to cancer that could be causing a rise in the liver enzymes.
It sounds like your doc is doing the right thing by referring you to a specialist if he or she is unable to identify the problem.
Try eating some foods that help the liver like kale, beets, carrots, burdock root, dandelion greens or broccoli and see if they help. Some people also take milk thistle to help the liver.
Take good care of yourself.