Following press reports of studies carried out at the Mayo Clinic, Rochester, Minnesota which found that EGCG was able to kill cancer cells in vitro from patients with chronic lymphocytic leukaemia (CLL), four patients with low grade B-cell malignancies who were attending the clinic independently started taking over-the-counter EGCG products.

Now the clinic reports that three of these have shown clear improvements with regression in their cancer. Although spontaneous remission/regression is occasionally observed in individuals with low grade B-cell malignancies, such events are rare.

A National Cancer Institute sponsored phase I/II trial of de-caffeinated green tea extracts for patients with asymptomatic, early stage CLL opened at the Mayo Clinic in August 2005. (Leukemia Research, In Press, Corrected Proof, Available online 1 December 2005).