enroll enough patients to produce a statistically significant result. Targeted tumor treatment A major challenge in cancer treatment is to find better ways to specifically target tumors with drugs and chemotherapeutic agents in order to provide a more effective, localized dose and to minimize exposure of healthy tissue in other parts of the body to the potentially adverse effects of the treatments. The accessibility of different tissues and organs to anti-tumor drugs contributes to this challenge. For example, the blood–brain barrier blocks many drugs that may otherwise be effective against brain tumors. In November 2009, a new, experimental therapeutic approach for treating glioblastoma was published in which the anti-tumor drug Avastin was delivered to the tumor site within the brain through the use of microcatheters, along with mannitol to temporarily open the blood–brain barrier permitting delivery of the chemotherapy into the brain. Public education and support An important aspect to the war on cancer is improving public access to educational and supportive resources, to provide individuals with the latest information about cancer prevention and treatment, as well as access to support communities. Resources have been created by governmental and other organizations to provide support for cancer patients, their families and caregivers, to help them share information and find advice to guide decision making. See also References Oncology Health policy in the United States Metaphors referring to war and violence