Risk of cancer in children with AIDS

Context Population-based data on cancers associated with acquired immunodeficiency syndrome (AIDS) in children are lacking. Objective To determine risk of pediatric AIDS-associated cancers. Design, Setting, and Participants Using records from 11 locations in the United States for varying periods between 1978 and 1996, we linked data for children aged 14 years and younger at AIDS diagnosis to local cancer registry data. Main Outcome Measures Cancer frequency and, in the 2-year post-AIDS onset period, cancer incidence and relative risk (RR; measured as standardized incidence ratio), by cancer type. Results Among 4954 children with AIDS, 124 (2.5%) were identified as having cancer before, at, or after AIDS onset, including 100 cases of non-Hodgkin lymphoma (NHL), 8 of Kaposi sarcoma (KS), 4 of leiomyosarcoma, and 2 of Hodgkin disease; there were 10 other or unspecified cancers. Expected numbers for all cancers identified in the study sample, based on population rates (using area-specific registry data), were less than 1. In the first 2 years after AIDS diagnosis (5485 person-years), NHL incidence was 510 per 100 000 person-years (RR, 651; 95% confidence interval [CI], 432-941). Median time for developing NHL after AIDS diagnosis was 14 months (range, 3-107 months). The most common type of NHL was Burkitt lymphoma. However, the risk of primary brain lymphoma (91 per 100 000 person-years) was especially high (RR, 7143; 95% CI, 2321-16692), and 4 cases were diagnosed more than 2 years (range, 37-98 months) after AIDS onset. Leiomyosarcomas also tended to occur several years after AIDS onset, with 3 of the 4 cases occurring 33 to 76 months after AIDS diagnosis, whereas KS was reported only at or within 2 years of AIDS diagnosis. Hodgkin disease risk was also significantly increased (RR, 62; 95% CI, 2-342). Conclusions The spectrum of AIDS-associated pediatric cancers resembled that seen in adults, with the addition of leiomyosarcoma. Both primary brain lymphomas and leiomyosarcomas tended to occur in children surviving several years after AIDS onset. Because the expected numbers of these cancers in this population were less than 1 and because of the small numbers of some types of observed cancers, the RR estimates are imprecise and caution is warranted in their interpretation.