Objective: To determine the types and rates of cancers occurring in excess in the presence of infection with the human immunodeficiency virus type 1 (HIV-1).
Design: Cohort analytic study of HIV-infected and HIV-uninfected subjects followed for up to 12 years.
Setting: Fifteen hemophilia treatment centers.
Patients: A total of 1701 patients with hemophilia, of whom 1065 (63%) were HIV-1 seropositive.
Main outcome measures: Morphologic classification and incidence rates of cancers.
Main results: The incidence of non-Hodgkin's lymphoma after HIV seroconversion averaged 0.15 case per 100 person-years (95% confidence interval [CI], 0.08 to 0.25) and rose exponentially with increasing duration of HIV infection. Although the greatest absolute risk of lymphoma was in the oldest age group, the relative increase compared with general population rates was 38-fold in subjects 10 to 39 years old and 12-fold in older subjects (P less than .05). The CD4+ T-lymphocyte levels for lymphoma cases were similar to HIV-positive subjects without the acquired immunodeficiency syndrome (AIDS) who had been infected for the same length of time. The incidence of Kaposi's sarcoma was increased 200-fold (95% CI, 20 to 700). The incidence of cancers other than non-Hodgkin's lymphoma and Kaposi's sarcoma were not increased in the HIV-positive subjects (ratio of observed to expected cases, 0.9 [95% CI, 0.4 to 1.9]). The HIV-negative subjects had no significant increase in cancer incidence.
Conclusions: HIV infection has restricted effects on cancer incidence that are only partly explained by immunosuppression. Paradoxically, improvements in therapy of HIV infection that prolong survival may lead to further increases in HIV-associated lymphoma.