My condolences to you and your friend with advanced cancer of the liver and colon. Many cancer patients use medical cannabis products to help with a variety of symptoms related to their condition. The most common symptoms cannabis is used to help with in this setting are pain, nausea/poor appetite, sleep, and anxiety. Oral cannabis tinctures with high cannabidiol (CBD) and low THC content are usually well tolerated and useful for these symptoms. Some individuals prefer increasing the THC content gradually to gain additional benefit for appetite stimulation and sleep. Although some promising research is emerging regarding the anti-cancer properties of medical cannabis, I would not recommend using cannabis in the hope that it will reverse the natural course of liver or colon cancer since this has not been definitively demonstrated in human clinical trials. It is important that your friend keeps his or her oncologist aware of any cannabis consumption since in some cases doctors may deny access to potentially curative therapies like transplant or clinical trial chemo drugs based on cannabis use. A cannabis recommending physician can help your friend come up with a more tailored approach for finding relief in this situation.