My research to date has primarily focused on the epidemiology of prostate cancer and the identification of patient and tumor characteristics that could reduce overtreatment. My work has included intervention studies to evaluate survival, cost-effectiveness, and quality of life, as well the investigation of biomarkers associated with cancer risk and prognosis in population-based cohorts. Collaborating with research pathologists, urologists, medical oncologists, molecular biologists, immunologists, virologists, and bioinformaticists, I have utilized data from a large Swedish population-based studies (CaPS and PCBaSe) and a Swedish randomized trial (SPCG-4), Swedish clinical cohorts, the Physicians’ Health Study, and the Health Professionals Follow-up Study. In addition to prostate cancer epidemiology, I am pursuing studies related to the infectious etiology of other cancer sites. I am involved in ongoing studies of HPV infection in penile carcinoma and tumors of the head and neck, as well as the role of the oral microbiome in oropharyngeal cancer.