Yes be sure you don't take allopathic drugs with therapy. Dr Christian Tal Shaller who wrote "Amaroli 1 & 2" etc. advice against taking more than 1/2 cup per day if you have to take chemical drugs, otherwise you risk doubling your prescription if you take all the urine you pass.
The more the better to cure your cancer. What kind of cancer do you have? Specialists from India believe that massaging is as important as drinking. When you drink the urine you do not have all the beneficial elements that you get from a massage as the urine is broken down by the gastric juices. (I would have to trace that info). I think I read this in "The Golden Fountain" by Coen Van Der Kroon...
Also injecting urine might have something to biring that injesting wouldn't. I read of cases where urine was injected in tumors etc. One of the reasons is that it bypass the digestive system and the stomach acids etc... Lots of info on: http://naturinologie.info/english.html . Read the testimonials on cancer and there are also good articles.
Good Luck