Patients with HIV infection are at increased risk for certain malignancies. Most of these tumors represent virus-associated cell proliferations and virus specific immune deficiency is thought to play a key role in the pathogenesis of these diseases. Under such hypotheses, HAART induced HIV replication control and subsequent immune restoration should have dramatically decreased the incidence of these tumors. Several studies, performed in developed countries, have explored the variation of these incidences (per 1,000 pt.y) over the past 10 years. The major incidence decrease is observed for Kaposi’s sarcoma (KS), an HHV8 associated tumor, with a decline
from 15.2 to 4.9. However, this decline started before HAART era, does not concern other HHV8 associated tumors (Castleman’s disease, primary effusion lymphoma) and KS remains the first cancer in adults from central and east Africa. The impact of HAART on the incidence of non-Hodgkin’s lymphoma (NHL) was less consistent, with an incidence decline from 6.2 to 3.6, and concern primary brain lymphoma and immunoblastic lymphoma, both types being strongly associated with EBV, while the incidence of Burkitt’s lymphoma appears almost unchanged. In our experience, most NHLs observed after 1996 have occurred in patients with uncontrolled HIV replication. Low nadir CD4 cell count, previous AIDS, prolonged immune deficiency and too short
exposure to HAART may partially explain the cases observed in patients with undetectable viral load. No significant trend in the incidence of Hodgkin’s disease, an other EBV associated tumor, has been detected. No clear change in the incidence of HPV associated anogenital tumors and of HBV or HCV associated hepatocellular carcinoma was observed. Although the initial lesion appears crucially dependent upon the degree of immuno suppression, the secondary development of cancer may take years and may be less influenced by HAART. Even if it is well established that immune deficiency predisposes to a variety of cancer, the specific mechanism(s) involved in each tumor type need to be further elucidated. The relative risk of developing an HIV
associated malignancy remains high and an increased relative morbidity and mortality is associated with these tumors. As therapies improve the survival of AIDS patients, the cumulative risk of developing or dying from cancer is likely to increase.
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