My child hates taking medicine. What can I do to treat cancer?

Patience....... Depending on his illness, to help his quality of life and hopefully lead to a long life there may not be another way other than taking some medicines. Depending on your child's and the regimen recommended you might consider: 1- making a game of the medicine routine with a small reward/prize at the completion 2- ask the compounding pharmacy if there are ways to make the drugs more palatable.
Follow MD advice. Cancer is a serious, life threatening issue and you need to follow your doctor's advice. We all hate taking medication, but is not a matter of taste or choice.
Find out why. I would recommend finding out why your child hates taking medicine. Is it because it tastes bad? Is it because the child equates medicine to being poked with needles? Is it because the child is scared of the unknown? It is possible to work around some of these anxieties so that your child can get the necessary cancer care.