While radiation therapy is common after breast conserving surgery, it is much less frequent after mastectomy, even among women for whom it would have clear life-saving benefit. This is according to a study from researchers at the University of Michigan (UM) Comprehensive Cancer Center.
The study looked at 2,260 women treated for breast cancer, assessing whether they 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 after mastectomy.
The study found that among patients who should receive radiation therapy according to medical guidelines, 95% of those who had lumpectomy went on to receive radiation, but only 78% of those who had mastectomy received radiation. Among women for whom radiation is less clearly beneficial, 80% of the lumpectomy patients had radiation while only 46% of the mastectomy patients did.
“A substantial number of breast cancer patients are being undertreated. One in five women with strong indications for radiation after mastectomy failed to receive it. Radiation can be a life-saving treatment,” study author Reshma Jagsi MD, DPhil, assistant professor of radiation oncology at the UM Medical School, said in a news release. “The fact that 95% 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. More attention needs to be paid to radiation after mastectomy.”
Results of the study appear online in the Journal of Clinical Oncology.
The study also found that doctor participation strongly influenced radiation receipt. Patients who reported 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 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.
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%. This is reduced by two-thirds if the patient undergoes radiation treatments, and overall survival is improved.
