Alarm About Radiation Therapy

By Dr. Kathleen T. Ruddy

An article just published in the New England Journal of Medicine (NEJM) has raised unnecessary alarm about the risks and benefits of radiation therapy in the treatment of early-stage breast cancer.  Let’s see what we can do to put out at least some of the fire.

Women who have early-stage breast cancer are eligible for breast conservation – lumpectomy.  However, unless additional radiation therapy is given following their surgery, the recurrence of breast cancer in the breast is unacceptably high.  Adding radiation therapy lowers the risk of local recurrence of breast cancer to less than 1% per year.  Which is to say, only one woman in a hundred will experience a recurrence of breast cancer in their breast every year following radiation therapy.  At ten years, ten women will have had a local recurrence of breast cancer:  but the other 90 will still have their breasts, and the breasts will be cancer-free.

The study in NEJM reviewed women in Sweden and Denmark who had received radiation therapy between 1958 and 2001.  The researchers compared the risk for heart disease to the level of radiation each patient received as part of her treatment.  They found what other researchers had noted previously:  an increased risk for heart attack proportional to the amount of radiation exposure, and compounded by underlying and pre-existing cardiac risk factors.

What’s important about this study is not that radiation therapy increases the risk for heart attack – slightly (from 1.9% to 2.4% – 3.4%) – but that the data go back to a much earlier age when radiation therapy techniques were crude and blunt, and the heart and lungs were far more vulnerable to scatter radiation from cobalt 60 technique used in the 1950′s and 1960′s.

With modern technology, women who have radiation therapy as part of breast conservation have minimal exposure to their heart and lungs.

Furthermore, a meta-analysis of 17 studies comprising nearly 11,000 women recently showed that patients who have received radiation therapy for breast cancer have an improved overall survival.  They live longer.  Radiation therapy reduces local recurrence and it improves survival from breast cancer.  And it allows the vast majority – at least 90% of women – to keep their breasts.

Nothing is perfect.  Radiation therapy is no exception.  But state of the art radiation therapy techniques today allow women to keep their breasts and their lives.

Let’s hope that this more complete information about the risks and benefits of radiation therapy puts out some of the fire ignited by the NEJM study.

Reference

P. Hall, NEJM 2013, 368: 987-998