Washington: A significant analysis has found that while clinical trial data supports omitting radiation treatment in elderly women with early stage breast cancer, nearly two-thirds of them continue to receive it.
The results from a large, randomised clinical trial showed that adding radiation therapy to surgery plus tamoxifen does not reduce five-year recurrence rates or prolong survival in elderly women with early stage tumours.
Despite the findings, many doctors still administer radiation to these patients.
"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 Rachel Blitzblau from Duke University.
She noted that there could be many reasons for this, including concern about the relatively short duration of follow-up of five years.
To examine the extent to which elderly women still receive radiation to treat early stage breast cancer, Blitzblau and her colleagues analysed 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 percent of patients received some form of radiation therapy
From 2005 to 2009, 61.7 percent of the patients received such treatment, although there was a shift in the type of radiation therapy used.
Longer-term results of the trial that were published last year showed that recurrence rates continued to be low in women who forewent radiation.
Blitzbau noted that it will be interesting to see if these findings will have a larger impact on practice patterns.
The findings were published online in Cancer, a peer-reviewed journal of the American Cancer Society.