Worldwide Cancer Research has not yet funded any research looking at the effects of cannabis on cancer. If, in future, we receive applications for funding to study the effects of cannabis or its derivatives on cancer, they will be considered in the same way as all the other applications we receive. The only criterion we use to award research funding is scientific quality; we do not prioritise any aspects of basic cancer research over others.
While some people claim that cannabis has been proven to cure cancer, there is nowhere near enough scientific evidence to back up these claims. There have been some early laboratory studies which have given promising results, as well as some studies where the results were less promising. Unfortunately, killing cancer cells in the laboratory is much easier than killing cancer cells in a person. Many things that look promising in early stages of research ultimately do not turn out to be good cancer treatments. Until a potential new cancer treatment has gone through the full process of testing in animals and people, we cannot be sure that it works.
What decades of cancer research have told us is that cancer is an extremely complex disease. It varies enormously, not only between its different forms, but also from person to person and from tumour to tumour. Because of this, it seems extremely unlikely that there could ever be a single cure for all cancers, and claims to this effect should always be viewed with scepticism.
There is some evidence that cannabis or cannabis derivatives might help with cancer symptoms and treatment side effects, for example, sickness caused by chemotherapy. However, there have been only a few small studies in this area so we cannot yet say for sure. More information about this, as well as research into cannabis as a cancer treatment can be found on the National Cancer Institute website.