Look around the net, you'll find a lot of studies detailing how both THC and CBD are beneficial for dealing with cancer.
It stops the signal to the body to build more blood vessels to the tumor
It kills cancer cells on contact
It helps cancerous sells convert back to normal cells
The most effective method of delivery is as a suppository. You use 1/3rd the dosage and the oils go straight to your heart and lungs after being absorbed by your colon.