Green tea appears to be a weapon against leukemia, according to Tait Shanafelt, a hematologist at the Mayo Clinic in Roch-ester, Minnesota and lead author of a study published in the online issue of the Journal of Clinical Oncology.

The positive results were discovered during early leukemia clinical trials using the chemical epigallocatechin gallate, a substance found in green tea.

"The majority of individuals who entered the study with enlarged lymph nodes saw a 50% or greater decline in their lymph node size," said Shanafelt. "Patients tolerated the green tea extract at very high doses."

Patients suffering from incurable chronic lymphocytic leukemia, the most common type of leukemia in the US, were used in the trials. According top te researchers, about half of all early stage patients have an aggressive form of the cancer that that results in an early death. The green tea extract can stabilize early-stage patients, possibly working in tandem with other treatments.

According to the report, the 33 patients in the trial received variations of eight different oral doses of Polyphenon E, a pro-prietary compound whose primary active ingredient is epigallocatechin gallate, of from 400 to 2,000 mg twice daily. Researchers believe that the maximum tolerated dose would exceed 4,000 mg daily.

In the second phase of clinical testing a similar number of patients will receive the highest dose administered from the previous trial.