ROCHESTER, Minn. - Mayo Clinic researchers are reporting positive results in early leukemia clinical trials using the chemical epigallocatechin gallate (EGCG), an active ingredient in green tea. The trial determined that patients with chronic lymphocytic leukemia (CLL) can tolerate the chemical fairly well when high doses are administered in capsule form and that lymphocyte count was reduced in one third of participants. The findings appear today online in the Journal of Clinical Oncology. “We found not only that patients tolerated the green tea extract at very high doses, but that many of them saw regression to some degree of their chronic lymphocytic leukemia,” says Tait Shanafelt, M.D., Mayo Clinic hematologist and lead author of the study. “The majority of individuals who entered the study with enlarged lymph nodes saw a 50 percent or greater decline in their lymph node size.”
CLL is the most common subtype of leukemia in the United States. Currently it has no cure. Blood tests have enabled early diagnosis in many instances; however, treatment consists of watchful waiting until the disease progresses. Statistics show that about half of patients with early stage diseases have an aggressive form of CLL that leads to early death. Researchers hope that EGCG can stabilize CLL for early stage patients or perhaps improve the effectiveness of treatment when combined with other therapies.