31.Cancer Clusters (Reviewed: 10/05/2006) - A fact sheet that describes what constitutes a cancer cluster and the process for reporting clusters. 32.Cancer Fund-Raising Organizations (Reviewed: 12/22/2003) - A fact sheet that offers suggestions on how to evaluate charities and provides names of organizations that monitor charity fund-raising practices. 33.Cancer Health Disparities (Reviewed: 03/11/2008) - A fact sheet that describes the current incidence and death rates for selected cancers among racial and ethnic groups living in the United States. It also includes a description of NCI programs that are addressing the causes of cancer health disparities. 34.Cancer Information Sources (Reviewed: 05/24/2005) - A fact sheet about sources of cancer information on the Internet, in libraries, and from government and private sector organizations. 35.Cancer of Unknown Primary Origin (Reviewed: 01/22/2004) - A fact sheet about cancer that has spread but whose original site in the body has not been found (unknown primary). 36.Cancer Research Funding (Reviewed: 07/07/2009) - A fact sheet about the National Cancer Institute's funding of cancer research. 37.Cancer Vaccines (Reviewed: 03/17/2009) - A fact sheet about cancer vaccines, which are intended either to treat existing cancers (therapeutic vaccines) or to prevent the development of cancer (prophylactic vaccines). 38.Cancer: Questions and Answers (Reviewed: 06/06/2005) - A fact sheet about prevention, symptoms, diagnosis, and treatment of cancer. 39.Care for Children and Adolescents With Cancer (Reviewed: 05/19/2008) - A fact sheet about children's cancer centers and health care approaches, including clinical trials for children with cancer. 40.Cellular Telephone Use and Cancer Risk (Reviewed: 09/09/2009) - This fact sheet outlines the available evidence regarding use of cellular/mobile telephones and cancer risk.