In general, the clinical setting and response to treatment of patients with AIDS-related lymphoma is very different from that of the non-HIV patients with lymphoma. The HIV-infected individual with aggressive lymphoma usually presents with advanced-stage disease that is frequently extranodal.
Common extranodal sites include the following:
- Bone marrow.
- Gastrointestinal tract.
Very unusual sites are also characteristic and include the following:
- Bile duct.
The clinical course is more aggressive, and the disease is both more extensive and less responsive to chemotherapy. Immunodeficiency and cytopenias, common in these patients at the time of initial presentation, are exacerbated by the administration of chemotherapy. Treatment of the malignancy increases the risk of opportunistic infections that, in turn, further compromise the delivery of adequate treatment.
Prognoses of patients with AIDS-related lymphoma have been associated with the following:
- Stage (i.e., extent of disease, extranodal involvement, lactate dehydrogenase level, and bone marrow involvement).
- Severity of the underlying immunodeficiency (measured by CD4 lymphocyte count in peripheral blood).
- Performance status.
- Prior AIDS diagnosis (i.e., history of opportunistic infection or Kaposi sarcoma).
Patients with AIDS-related PCNSL appear to have more severe underlying HIV-related disease than do patients with systemic lymphoma. In one report, this severity was evidenced by patients with PCNSL having a higher incidence of prior AIDS diagnoses (73% vs. 37%), lower median number of CD4 lymphocytes (30/dL vs. 189/dL), and a worse median survival time (2.5 months vs. 6.0 months). This report also showed that patients with poor risk factors-defined as Karnofsky performance status <70%, history of prior AIDS diagnosis, and bone marrow involvement-had a median survival time of 4.0 months compared with a good prognosis group without any of these risk factors, who had a median survival time of 11.3 months.
In another report (NIAID-ACTG-142), prognostic factors were evaluated in a group of 192 patients with newly diagnosed AIDS-related lymphoma who were randomly assigned to receive either low-dose methotrexate, bleomycin, doxorubicin, cyclophosphamide, vincristine, and dexamethasone (m-BACOD) or standard dose m-BACOD with granulocyte-macrophage colony-stimulating factor. No differences existed between these two treatments in terms of efficacy for disease-free survival, median survival, or risk ratio for death.[Level of evidence: 1iiA] On multivariate analysis , factors associated with decreased survival included age older than 35 years, history of intravenous drug use, stage III or stage IV disease, and CD4 counts of less than 100 cells/mm3. The median survival rates were 46 weeks for patients with one or no risk factors, 44 weeks for patients with two risk factors, and 18 weeks for patients with three or more risk factors. The International Prognostic Index may also be predictive for survival.[14,15,16] In a multicenter cohort study of 203 patients, in a multivariable Cox model, response to HAART was independently associated with prolonged survival (relative hazard = 0.32; 95% confidence interval, 0.16-0.62).[Level of evidence: 3iiiDii]