A new analysis has found that while clinical trial data support omitting radiation treatments in elderly women with early stage breast cancer, nearly two-thirds of these women continue to receive it. The findings are published early online in Cancer, a peer-reviewed journal of the American Cancer Society.
Results published in 2004 from a large, randomized clinical trial showed that adding radiation therapy to surgery plus tamoxifen does not reduce 5-year recurrence rates or prolong survival in elderly women with early stage tumors. Despite the findings, many doctors still administer radiation to these patients.
To examine the extent to which elderly women still receive radiation to treat early stage breast cancer, Rachel Blitzblau, MD, PhD, of Duke University, and her colleagues analyzed information from the nation's largest cancer registry, the Surveillance, Epidemiology and End-Results (SEER) database. The investigators identified 40,583 women older than 70 years of age who were treated with lumpectomy from 2000 to 2009. From 2000 to 2004, before the trial results were published, 68.6% of patients received some form of radiation therapy. From 2005 to 2009, 61.7% of patients received such treatment, although there was a shift in the type of radiation therapy used: fewer patients received standard whole breast radiation, and more received a short course of focused radiation treatment. The results indicate that publication of the trial results had only a very small impact on practice patterns.
"Our findings highlight the fact that it may be challenging for practitioners to incorporate clinical trial data that involves omitting a treatment that was previously considered standard of care," said Dr. Blitzblau. She noted that there could be many reasons for this, including concern about the relatively short duration of follow-up of five years. "If a treatment regimen has been working well, and data are new, there can be concern that de-escalation of treatment may ultimately be shown to worsen outcomes." However, the medical community as a whole is aware that there is a need for more financially efficient medical care that omits unnecessary treatments.
Longer-term results of the trial that were published last year showed that recurrence rates continued to be low in women who forewent radiation. Dr. Blitzbau noted that it will be interesting to see if these findings will have a larger impact on practice patterns.