Background:  As HIV-infected persons live longer, concerns about chronic illnesses, including cancers, persist. Recent trends in cancer are well described in HIV-infected adults but not in infected children. We describe cancer trends in 2 CDC cohorts of HIV-infected children: Pediatric Spectrum of HIV Disease (PSD) and LEGACY. Incidence of pediatric malignancies in the general pediatric population was 0.20 cases/1,000 person-years from 1984 to 2006, based on the Surveillance Epidemiology and End Results Program.

Methods:  PSD is an observational medical record study of HIV-infected children enrolled in 8 US regions from 1990 to 2004; LEGACY is a similar study conducted at 25 sites from 2005 to 2006. We evaluated the incidence of all cancers from 1984 to 2006 based on a person-time analysis (cases/1000 person-years). Retrospective data on incident cancers among enrollees prior to PSD’s initiation in 1990 were included. We compared characteristics of HIV-infected children with and without cancers; compared the incidence of all cancers, AIDS-defining cancers (ADC), and non-ADC (NADC) in the pre- (prior to 1997) and post-HAART eras; and calculated cancer incidence rate ratios (IRR) and 95% confidence intervals assuming a Poisson distribution.

Results:  There were 112 incident cancers, 71 ADC and 41 NADC, among 5,735 participants contributing 37,240 person-years of follow-up time; 22 of 112 (19%) cancers occurred retrospectively before 1990. Comparing children with and without cancer, the median age was 6.8 vs 8.6 years (P =0.44), 46% vs 49% (P =0.21) were female, and 81% vs 85% (P =0.11) were perinatally infected. Non-Hodgkin lymphoma comprised 90% of the ADC, while Kaposi sarcoma (10%) was uncommon and only diagnosed in the pre-HAART era. The most common NADC were leukemia (20%) and bone and soft tissue cancers (17%).The overall incidence of cancer was 3.0 cases/1000 person-years. The IRR of cancer in the pre-HAART vs post-HAART eras for all cancers was 1.52 (1.04 to 2.21), for ADC was 2.50 (1.49 to 4.19), and for NADC was 0.69 (0.373 to 1.29) (Figure 1). The IRR of cancer among perinatally vs non-perinatally HIV-infected children did not differ significantly (IRR = 1.38, 95%CI 0.86 to 2.23).

Conclusions:  The overall cancer incidence in 2 CDC pediatric HIV cohorts was elevated relative to that of the general U.S. pediatric population. In the HAART era, pediatric ADC incidence declined significantly, similar to adults, and pediatric NADC incidence did not significantly increase in HIV-infected children.