Radiotherapy Prevalent in Older Women With Early-Stage Breast Cancer Despite Limited Benefit

Rachel Blitzblau, MD, PhD

Despite research findings that toxicities outweigh benefits when women over the age of 70 are treated with radiation for their early-stage breast cancer, the treatment remains commonplace 10 years later, a new study has found.

Researchers say the trend signals a need for improved patient—provider communication, so that the “right patients get the right treatment at the right time.”

The results follow on the 2004 large, prospective CALGB 9343 study, which reported limited benefit for adding radiotherapy to tamoxifen after lumpectomy among older women. Although that study by the Cancer and Leukemia Group B found a small but statistically significant reduction in the rate of cancer recurrence, the radiation did not improve overall survival when the data were analyzed after 5 years and again in 2012, which showed the side effects worsened.

“The discussion at the time of the first CALGB report in 2004 was that we should consider omitting radiation for these women, because the small observed benefits might not be worth the side effects and costs,” explained study author Rachel Blitzblau, MD, PhD, in a statement, adding that the side effects included fatigue, discomfort, and changes in the radiated breast tissue.

Nevertheless, practice changed little following publication of these findings, with approximately two-thirds of women >70 years of age still getting radiation therapy, said Blitzblau, the Butler Harris Assistant Professor of Radiation Oncology at Duke University Medical Center.

For their study, reported online December 8 in the journal Cancer, Blitzblau and colleagues analyzed cancer treatment patterns from the SEER national health registry, identifying 40,583 women aged ≥70 years who were treated with breast-conserving surgery for stage I estrogen receptor— and/or progesterone receptor–positive breast cancer.

The investigators found that before the CALGB study results were published in 2004, 68.6% of older women who would have been eligible for enrollment in the CALGB trial received radiation therapy. In the 5 years after the study was first reported, the rate dropped, but only slightly, to 61.7% (P <.001).

“The publication of the trial had only a very small impact on practice patterns,” said Blitzblau, underscoring how difficult it can be to change longstanding practice: “Our findings demonstrate the potential difficulty of incorporating clinical trial data that involves omitting a treatment that has been considered the standard of care.”

There is also lingering concern among both doctors and patients that reducing treatments may worsen outcomes for older women who are otherwise healthy and have longer life expectancies, Blitzblau said.

The findings of the current study highlight an important and increasingly difficult challenge for physicians, she continued: “Striking the right balance between offering effective treatments while also acknowledging the need for more financially efficient medical care.”

“As we work toward more efficient and evidence-based medical practice in all medical specialties, we will need to understand what processes may be needed to spur change.”

Palta M, Palta P, Bhavsar NA, et al. The use of adjuvant radiotherapy in elderly patients with early-stage breast cancer. Changes in practice patterns after publication of Cancer and Leukemia Group B 9343 [published online ahead of print December 8, 2014]. Cancer.