The cumulative incidence of certain cancers has increased among individuals with HIV because they are living longer, according to data from the North American AIDS Cohort Collaboration on Research and Design of International Epidemiologic Databases to Evaluate AIDS (NA-ACCORD).
Researchers observed an especially high cumulative incidence by age 75 years of Kaposi’s sarcoma, non-Hodgkin’s lymphoma and lung cancer.
Michael J. Silverberg
Michael J. Silverberg, PhD, MPH, research scientist in the division of research at Kaiser Permanente Northern California, and colleagues sought to determine if the increase in cancer incidence was due to individuals living longer or to a true increase in the incidence of cancer in this population.
Researchers compared time trends in the incidence of cancer by age 75 years among 86,620 individuals with HIV and 196,987 individuals without HIV from the NA-ACCORD who were followed between 1996 and 2009.
Compared with individuals without HIV, the cumulative incidence by age 75 years of Kaposi’s sarcoma (4.4% vs. 0.01%), non-Hodgkin’s lymphoma (4.5% vs. 0.7%) and lung cancer (3.4% vs. 2.8%) appeared greater in individuals with HIV in the most recent calendar era (2005 to 2009). Researchers also observed a greater cumulative incidence of anal cancer (1.5% vs. 0.05%), liver cancer (1.1% vs. 0.4%) and Hodgkin’s lymphoma (0.9% vs. 0.09%) in the HIV population.
However, there did not appear to be a higher incidence of colorectal cancer, melanoma or oral cavity/pharyngeal cancer.
Among individuals with HIV, there was a significant decline in the annual trend of cumulative cancer incidence for Kaposi’s sarcoma (–4% per year), non-Hodgkin’s lymphoma (–5%) and death (–9%). There were significant increasing incidence trends for anal cancer (6%), colorectal cancer (5%) and liver cancer (6%); however, researchers observed no increasing hazard rate trends for these cancers, which suggests the decreasing mortality rate trend presented a greater risk for diagnosis.
Although hazard rate trends decreased for lung cancer (–4%), Hodgkin’s lymphoma (–5%) and melanoma (–6%), researchers observed no cumulative incidence trends, likely due to the compensating effect of the declining mortality rate.
The researchers identified some limitations with their study. They did not include secular trends in cancer screening, smoking or viral co-infections because these data were not collected across all cohorts. Additionally, the measure of cumulative incidence relied on age-specific follow-up for a small percentage of time for each patient, which may manifest as artificially steep increases in cumulative incidence if the birth cohorts had a higher risk for cancer.
“The effectiveness of antiretroviral therapy has enabled persons with HIV to live long enough to have cancer,” Silverberg and colleagues wrote. “The high cumulative incidences by age 75 years for Kaposi’s sarcoma, non-Hodgkin’s lymphoma and lung cancer indicate that public heath efforts need to be intensified to promote early, sustained antiretroviral therapy, smoking cessation and lung cancer screening.
“As the population with HIV ages, future estimates of cumulative incidence could be stratified by levels of cancer risk factors such as CD4+ count, smoking, alcohol consumption, and HBV or HCV infection, to more accurately inform patients and providers about risk and to help further target prevention efforts.” – by Anthony SanFilippo
Disclosure: Silverberg reports research grants from Merck and Pfizer. Please see the full study for a list of all other researchers’ relevant financial disclosures.