Though radiation therapy is commonly administered following breast-conserving lumpectomy surgery, it’s much less frequently administered after mastectomy, even to women for whom it would offer clear life-saving benefits, according to a recent study by researchers at the University of Michigan (U-M) Comprehensive Cancer Center, Ann Arbor.
The study, which was published online on March 29 in the Journal of Clinical Oncology, surveyed 2,260 women treated for breast cancer, assessing whether they had had lumpectomy or mastectomy, and whether they would be strong candidates for radiation therapy. Women who have particularly large tumors or cancer in four or more of their nearby lymph nodes are recommended to have radiation. In patients with strong indications for radiation after mastectomy, their risk of the cancer coming back in the chest wall or surrounding areas can exceed 30 percent. This is reduced by two-thirds if the patient undergoes radiation treatments, and overall survival is improved.
The study found that among patients who should receive radiation therapy according to medical guidelines, 95 percent of those who had lumpectomy went on to receive radiation, but only 78 percent of those who had mastectomy received radiation. Among women for whom radiation is less clearly beneficial, 80 percent of the lumpectomy patients had radiation, while only 46 percent of the mastectomy patients did.
“A substantial number of breast cancer patients are being under-treated. One in five women with strong indications for radiation after mastectomy failed to receive it. Radiation can be a life-saving treatment,” said study author Reshma Jagsi, MD, DPhil, assistant professor of radiation oncology at the U-M Medical School.
“The fact that 95 percent of patients who had lumpectomy received radiation in the two metropolitan areas we studied indicates that we can do better than we are currently doing for the selected mastectomy patients who also need radiation,” Jagsi added. “More attention needs to be paid to radiation after mastectomy.”
The study also found that doctor participation strongly influenced radiation receipt. Patients who reported that their surgeon was involved in the decision to receive radiation were more likely to receive radiation than patients whose doctor was less involved.
“Even patients who wanted to avoid radiation therapy were very likely to receive it if their surgeons were highly involved in the decision process. We need to do a better job of educating both patients and physicians regarding the benefits of radiation after mastectomy in certain circumstances, and we need to encourage physicians to help their patients as they make these important decisions,” Jagsi said.
