Combination therapy improves AIDS-related lymphoma outcome

Combining aggressive HIV therapy and chemotherapy significantly improves the survival rates of HIV-positive men and women treated for lymphoma, according to a new study.

Published in the April 1, 2006 issue of CANCER (http://www.interscience.wiley.com/cancer-newsroom), a peer-reviewed journal of the American Cancer Society, the study reveals that combination therapy showed the greatest benefit for HIV patients suffering from aggressive malignant non-Hodgkin's lymphoma. This benefit was most pronounced in HIV patients without severely impaired immune functions. These so-called "standard risk" patients responded as well to therapy and survived as long as lymphoma patients without HIV.

Lymphomas are cancers of the immune system's white blood cells. They are treated with chemotherapy, often consisting of a multi-drug regimen using cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP). People with HIV, a virus that depletes integral, specialized white cells called CD-4 cells, are at increased risk of developing lymphomas, particularly aggressive, fast-growing non-Hodgkin type lymphomas. These are called "AIDS-related lymphomas" (ARL) and generally have a poorer prognosis than non-HIV-related lymphomas. Highly active antiretroviral therapy (HAART) revolutionized care of HIV-positive men and women. It not only improves laboratory indicators, such as increased CD-4 cells and reduced viral loads, but also significantly improves survival and delays the onset of AIDS and AIDS-related cancers, including lymphomas.

With the lack of study data to show the efficacy of maintaining HIV-positive patients on HAART while they are treated with chemotherapy for ARL, oncologists are hesitant to expose HIV patients to hypothetical drug toxicities related to combining the therapies. Researchers led by Rudolf Weiss, M.D., of Specialist Practice for Hematology, Oncology and Infectious Diseases in Bremen, Germany, treated 72 HIV-patients with ARL divided into high-risk and standard-risk cohorts with combined CHOP and HAART to evaluate the safety and efficacy of the combined regimen.

The investigators found combined therapy improved survival rates for patients with ARL and standard level of risk to rates comparable to those in non-HIV patients with lymphoma treated with CHOP and superior to previously published rates achieved by CHOP alone. For standard-risk ARL patients 79 percent achieved complete remission, and after 47 months of follow-up and study's end, more than 50 percent of patients survived. Moreover, only 40 percent reported moderate drug toxicity. For high-risk ARL patients, only 29 percent achieved complete remission and median survival was only 7.2 months. Sixty-nine percent reported moderate toxicity.

"The present study showed that our risk-adapted strategy for concomitant administration of HAART with CHOP is effective and safe," the authors concluded.

Source : John Wiley & Sons, Inc.