Established Oncogenic Viruses & Associated Cancers
1. Epstein-Barr Virus (EBV / HHV-4)
• Burkitt lymphoma
• Hodgkin lymphoma
• Nasopharyngeal carcinoma
• Some gastric (stomach) carcinomas
• Other lymphomas and rare leiomyosarcomas (especially in immunocompromised people)
2. High-risk Human Papillomaviruses (HPV, especially types 16 & 18)
• Cervical cancer (nearly all cases)
• Anal cancer
• Oropharyngeal (throat) cancer
• Vulvar, vaginal, and penile cancers
3. Hepatitis B Virus (HBV)
• Hepatocellular carcinoma (liver cancer)
• (Often through chronic inflammation and cirrhosis)
4. Hepatitis C Virus (HCV)
• Hepatocellular carcinoma (liver cancer)
• Some non-Hodgkin lymphomas
5. Human T-cell Lymphotropic Virus Type 1 (HTLV-1)
• Adult T-cell leukemia/lymphoma (ATLL)
6. Kaposi Sarcoma-Associated Herpesvirus (KSHV / HHV-8)
• Kaposi sarcoma
• Primary effusion lymphoma
• Multicentric Castleman disease
7. Merkel Cell Polyomavirus (MCPyV)
• Merkel cell carcinoma (rare but aggressive skin cancer)
8. Hepatitis D Virus (HDV) — (added/confirmed in 2025 IARC evaluation)
• Hepatocellular carcinoma (liver cancer, usually in co-infection with HBV)
Human Immunodeficiency Virus (HIV-1) — (Group 1, indirect)
• Dramatically increases risk of cancers caused by the viruses above (especially HPV-related, KSHV-related Kaposi sarcoma, and EBV-related lymphomas) due to immune suppression. Not directly transforming cells like the others.