The groups were statistically indistinguishable in estimated 5-year rates of overall survival, at about 93%, and disease-free survival, at about 85%.
The 5-year rate of lymphedema – defined in the study as the need for treatment with a sleeve garment, compression therapy, or lymph drainage therapy, or presence of the condition on physical examination – was 28% with ALND and 14% with axillary radiation therapy (P less than .0001), according to Dr. Rutgers.
"The side effects of radiotherapy cannot be neglected but are limited," he commented. "We looked at many other potential side effects of radiotherapy. There was no excess of cardiac problems, a very small excess of radiation pneumonitis; there was no effect on the brachial nerves."
The groups did not differ with respect to overall quality of life, but there were trends toward greater difficulty moving the arm after radiation therapy and greater swelling after ALND.
Dr. Rutgers disclosed no conflicts of interest related to the research.