Brian Hoyle

March 07, 2011

March 7, 2011 (Boston, Massachusetts) — An analysis of more than 5800 people diagnosed with AIDS in childhood prior to the 1996 initiation of highly active antiretroviral therapy (HAART) has revealed that such people have an increased risk for Kaposi's sarcoma and non-Hodgkin's lymphoma.

Although the risk for these cancers has declined in the HAART era, their risk in this population remains higher than in the general population, and the risk for leiomyosarcoma is unchecked by HAART. Follow-up of the cohort has been as long as 10 years.

The study results, presented here at the 18th Conference on Retroviruses and Opportunistic Infections by Edgar Simard, PhD, from the National Cancer Institute in Bethesda, Maryland, point out the importance of close monitoring of this segment of the AIDS population during adolescence and adulthood.

"This is the largest study to date to evaluate the long-term effect of childhood AIDS. People who are diagnosed with AIDS during their childhood or early adolescence and who survive remain at risk for Kaposi's sarcoma and non-Hodgkin's lymphoma, although the risk of these cancers has declined in the HAART era. As well, those diagnosed with AIDS during childhood remain at greater risk for leiomyosarcoma," Dr. Simard told Medscape Medical News.

The study was prompted by the findings that HAART does not completely restore the immune damage caused by HIV infection. The consequence might be more maladies — including cancer — in children, adolescents, and young adults than in older individuals with AIDS.

"This is the most comprehensive and perhaps the first study to investigate children who contracted HIV and their cancer incidence," Dirk P. Dittmer, PhD, from the University of North Carolina School of Medicine in Chapel Hill, told Medscape Medical News.

AIDS registry records from 15 regions in the United States were matched with cancer registries to identify cancers diagnosed up to 10 years after the diagnosis of AIDS in 5846 subjects, ranging in age from birth to 14 years at the time of diagnosis. The cancer risks relative to the general population in the pre-HAART era (1980 to 1995) and HAART era (1996 to 2008) were assessed with standardized incidence ratios (SIR). The changes in cancer incidence in those diagnosed with AIDS were determined in the 2 time periods.

Of the 5846 people, 72.5% were diagnosed with AIDS in the pre-HAART era and 27.5% were diagnosed in the HAART era. The majority were male (51.7%), non-Hispanic blacks (61.7%), and 4 years or younger at AIDS onset (67.5%).

The 10-year risk for any cancer was higher in those diagnosed with AIDS than in the general population in the pre-HAART era (SIR, 41; 95% confidence interval [CI], 32 to 51) and, although reduced, was also higher in the HAART era (SIR, 19; 95% CI, 13 to 26).

More specifically, the widespread implementation of HAART was associated with a lower incidence of all cancers (relative risk [RR], 0.38; 95% CI, 0.23 to 0.64; n = 106), Kaposi's sarcoma (RR, 0.13; 95% CI, 0.02 to 0.75; n = 20), and non-Hodgkin's lymphoma (RR, 0.39; 95% CI, 0.21 to 0.74; n = 64).

However, the rate of Kaposi's sarcoma remained higher in comparison to the general population, even in the HAART era (pre-HAART SIR, 1706; 95% CI, 994 to 2832; HAART SIR, 1254; 95% CI, 259 to 3666).

The rate of non-Hodgkin's lymphoma declined significantly following the advent of HAART, compared with the general population (pre-HAART SIR, 341; 95% CI, 245 to 463; HAART SIR, 130; 95% CI, 82 to 194; < .001).

The only non-AIDS-defining cancer that displayed an elevated risk was leiomyosarcoma (pre-HAART SIR, 870; 95% CI, 237 to 2229; HAART SIR, 554; 95% CI, 180 to 1292; = .41; n = 9).

"Treatment may not differ for those who have survived childhood AIDS. But we need to recognize that, for this population, the risk of cancer is greater. We need data from longer-term observations to investigate the influence of lifestyle factors and to expand the research to include other factors, such as economic status," Dr. Simard told Medscape Medical News.

"This work highlights the changing dynamics of the HIV epidemic. As people with HIV live longer thanks to HAART, we urgently need to understand how to treat their comorbidities. Foremost among them is cancer. The risk of cancer following a childhood AIDS diagnosis is elevated, compared with the general population," Dr. Dittmer noted.

"This raises several questions: Should we increase screening for AIDS-defining cancers or predisposing cancer virus infections in HIV positive adolescents? What is the biological mechanism that leads to an increased risk of leiomyosarcoma in HIV positive children?" Dr. Dittmer asked.

Dr. Simard and Dr. Dittmer have disclosed no relevant financial relationships.

18th Conference on Retroviruses and Opportunistic Infections (CROI): Abstract 82LB. Presented March 1, 2011.