Researchers have developed a new vaccine that may be able to substantially lengthen the lifespan of patients with the glioblastoma multiforme variant of brain cancer.
During a study of 23 cancer patients, it increased survival times by at least 18 months, and only 4 of the patients died during the trial period. The vaccine works by "tagging" cancer cells with a protein that tricks the immune system into believing they are foreign, forcing it to attack the cells and destroy them. Unfortunately, however, it appears that the vaccine only works until the cancer evolves to use different receptors, at which point it becomes ineffective.
http://news.bbc.co.uk/2/hi/health/4942840.stm