There are many herbs that can and have been used for cancer. Personally, I like formulas, since cancer, like most diseases, does not have a single cause or effect on the body.
Formulas can address more than one part of the body, or more than one system of the body at a time.
Also, I believe there is a synergistic quality to good formulas - the combination of herbs works together better than all the single herbs, separately. This site is the official site for this tea and it gives the information that you would need to decide if this is a formula that you would like to try. Essiac - There is no need for me to duplicate this well written site. This is a very popular formula for a tea that has been taken for cancer and other serious diseases. I don't have any personal experience with it, but it is well known.