(HealthDay News) — For women with breast cancer and one to three positive lymph nodes, radiotherapy is beneficial after mastectomy and axillary dissection, according to a study published online March 19 in The Lancet.
Paul McGale, Ph.D., and colleagues from the Early Breast Cancer Trialists’ Collaborative Group in Oxford, U.K., conducted a meta-analysis of individual data for 8,135 women with breast cancer with only one to three positive lymph nodes. Participants were randomly assigned to treatment groups during 1964 to 1986 in 22 trials involving radiotherapy to the chest wall and regional lymph nodes after mastectomy and axillary surgery versus surgery with no radiotherapy.
The researchers found that radiotherapy correlated with significant reductions in locoregional recurrence, overall recurrence, and breast cancer mortality in 1,314 women with axillary dissection and one to three positive nodes. For the 1,133 of these women who were in trials in which systemic therapy was given in both trial groups, radiotherapy correlated with significantly reduced locoregional recurrence, overall recurrence, and breast cancer mortality. Significant reductions were also seen for the 1,772 women with axillary dissection and four or more positive nodes.
“After mastectomy and axillary dissection, radiotherapy reduced both recurrence and breast cancer mortality in the women with one to three positive lymph nodes in these trials even when systemic therapy was given,” the authors write.