January 01, 2020

No chemo for many women with breast cancer

According to a recent large-scale study called TAILORx, doctors can now more confidently recommend forgoing chemotherapy for many women with the most common type of early-stage breast cancer. The study was published in New England Journal of Medicine and focused on about 10,000 women with breast cancer that was hormone receptor (HR) positive, human epidermal growth factor receptor 2 (HER2) negative and axillary node negative.

Cancer experts often use a gene expression test of a tumor to gauge the likelihood of cancer recurrence after surgery and then recommend anti-estrogen therapy, chemotherapy or both. Recurrence risk is scored from 0 to 100. Women with scores 10 and below have low recurrence risk and receive only anti-estrogen therapy. Women with scores over 25 have higher recurrence risk, making it necessary to receive both anti-estrogen therapy and chemotherapy.

The TAILORx study focused on women with scores in the middle range of 11 to 25 and randomly assigned these women to a treatment of either anti-estrogen therapy alone or chemotherapy with anti-estrogen therapy. There was very little difference in the rates of cancer recurrence and survival between the two groups five and nine years later.

Mayo Clinic experts say this study has already changed how patients are treated. In the past, doctors tended to err on the side of offering chemotherapy to women with a middle-range recurrence score. But this study showed that about 70% of women with the type of breast cancer described above — including all those with low scores and most with midrange...