Raw thc and cbd oils being used for pain/cancer

My grandad has just been diagnosed with lung cancer and already has copd. He is in excruciating pain constantly as the pain meds he has been given aren’t working very well. We as a family decided to get him some thc and cbd which he puts on a piece of bread and eats. It seems to be working as far as the pain is concerned. It is not legal here in the uk as far as I know but when someone you love is keeled over in pain you do anything you can to help relive that pain. Does anyone have any success stories or not so good ones?