 Among newly diagnosed cancer patients presenting to SWOG-affiliated community and academic oncology clinics, estimate the prevalence of human immunodeficiency virus HIV, hepatitis B HBV, and hepatitis C HCV infection. Prevalence estimates will be further stratified: by whether infection with the viruses is known, as reported by patients andor their physician prior to study testing, vs. unknown; by presenting cancer type, and by self-reported risk factors for each virus. 