A large, randomized clinical trial of estrogen and progestin as part of a Women's Health Initiative study indicated that breast cancer survivors who took hormone replacement therapy (HRT) to relieve menopausal symptoms had 3 times as many recurrences of cancer as those who did not take HRT. The 1997 Swedish study followed 434 women for a median of 5 years. Researchers found that 26 women in the HRT group and only 7 in the non-HRT group experienced a recurrence of breast cancer. The study was terminated due to the high risk of cancer recurrence from even short-term use of HRT. The study was neither blinded nor placebo-controlled, and recruitment fell short of the 1300- women goal. Despite the study's limitations, JoAnne Zujewski, MD, a medical oncologist specializing in breast cancer at the National Institutes of Health Clinical Center in Bethesda, Md, said, "As a practical matter, given what we already know about the serious risks and extremely limited benefits of HRT, these findings can be considered definitive."