Question: Why do I need radiation therapy if I had my breast cancer removed by surgery?
Answer: Radiation therapy is necessary following surgical removal of a breast tumor to ensure the best control of the disease, and to get the lowest rate of recurrence. We've asked the question: "Can we get away without radiation, does the surgery itself do the job?" And, in one of the first big trials done in this area, a group of women was treated with surgery alone. No radiation. And the recurrence rates start to push towards 40 percent -- in contrast to somewhere around 10 percent when radiation is added. So it's quite a dramatic effect.
Over the years, we've repeated that study, trying to find a more and more favorable group of women who can be treated with radiation alone. And, in every single study done, the administration of radiation lowers the recurrence rate even further. It's gotten to the point where there has not been a population of patients with breast cancer, who've been identified, that do not gain a benefit from the addition of radiation. So today, to make a broad, general statement -- every woman who has breast conservation, and who has an excision, should receive radiation therapy following that excision.