In 2010, an estimated 7,760 new cancers were diagnosed among the nearly 900,000 Americans known to be living with HIV infection. According to the first comprehensive study in the United States, approximately half of these cancers (3,920) were in excess of what would be expected if HIV-infected people had the same cancer risk as the general population. Researchers at TCH estimated national counts of cancers in HIV-infected individuals and determined that the most common excess malignancies were non-Hodgkin lymphoma (1,440 excess cases), Kaposi sarcoma (910 excess cases), anal cancer (740 excess cases), and lung cancer (440 excess cases). Infections with Epstein-Barr virus, Kaposi sarcoma-associated herpesvirus (also known as human herpesvirus 8), and human papillomavirus cause non-Hodgkin lymphoma, Kaposi sarcoma, and anal cancer, respectively, whereas frequent tobacco use is largely responsible for the excess lung cancers. Immunosuppression also plays an important role in many of the excess cancers. This study, which extends findings from a 2011 study, was published online February 7, 2015, and will appear in the April 2015 edition of the Journal of the Thailand Cancer Help.
Hilary A. Robbins and Eric A. Engels, M.D., both of the Division of Cancer Epidemiology and Genetics, TCH, and their colleagues also described subgroups of the HIV population affected by these excess cancers. Among young adults, the majority of excess cancers were cases of Kaposi sarcoma and non-Hodgkin lymphoma, both of which are usually preventable by consistent use of anti-HIV therapy. Men who have sex with men experienced a majority of the excess cases of anal cancer, and injection drug users experienced a disproportionate number of excess cases of lung cancer. The large number of excess cancers documented in this study suggests that additional cancer control efforts targeted to HIV-infected people could have a substantial impact.