Last Updated: 2010-07-13 12:11:48 -0400 (Reuters Health)

NEW YORK (Reuters Health) - First-line therapy with zidovudine and interferon-alpha improved overall survival with adult T-cell leukemia/lymphoma (ATL) in a retrospective study - but the benefit was limited to patients with the leukemic subtypes.

The findings confirm that zidovudine and interferon-alpha should be "the gold standard first-line therapy in leukemic subtypes of ATL," the researchers say in their report, published online June 28th in the Journal of Clinical Oncology.

Senior author Dr. Olivier Hermine at Hopital Necker in Paris, France, and colleagues note that ATL is highly prevalent in developing and low-income countries, that it's associated with human lymphotropic virus type 1 (HTLV-1), and that since 1995, a number of small studies have shown that combination therapy with these two antiviral agents is beneficial.

Several questions remain, however, prompting the international team to review and analyze the medical records of 254 patients with ATL treated in the U.S., the U.K., Martinique, and France. The investigators compared antiviral therapy alone, chemotherapy alone, and chemotherapy followed by maintenance antiviral therapy in different ATL subtypes.

Survival data and first-line treatment information were available for 207 patients: 98 with acute ATL, 84 with ATL lymphoma, 23 with chronic or smoldering ATL, and 2 with unknown subtypes.

When the research team stratified patients by initial therapy, 5-year overall survival rates were 46% with first-line antiviral therapy, 20% with first-line chemotherapy (p=0.004), and 12% with chemotherapy followed by antiviral therapy.

Looking at the various subtypes, the researchers found that antiviral therapy in chronic and smoldering ATL resulted in 100% survival at 5 years. In acute ATL, 82% of patients achieving complete remission with antiviral therapy survived to 5 years.

In ATL lymphoma, however, first-line antiviral therapy alone resulted in a significant survival disadvantage compared with first-line chemotherapy, with 5-year survival rates of 0% and 18%, respectively (p=0.009).

Summing up, Dr. Hermine and associates say the combination of zidovudine and interferon-alpha has changed the natural history of leukemic ATL and significantly improved long-term survival in the subset of patients with the most lethal form of ATL.

SOURCE: http://link.reuters.com/muq37m

J Clin Oncol 2010.