Radiotherapy to regional nodes in early breast cancer: an individual patient data meta-analysis of 14 324 women in 16 trials.

Early Breast Cancer Trialists’ Collaborative Group (EBCTCG).

Lancet 2023; 402: 1991-2003.

Sixteen trials including over 14,000 women were reported. Regional nodal radiotherapy significantly reduced breast cancer-related mortality (relative risk 0.87, 95 per cent confidence interval 0.8 to 0.94, P=0.001) and also all-cause mortality (0.9, 0.84 to 0.96, P= 0.0022. The effect was only in trials done after the 1980s suggesting improvements in radiotherapy since then.

Comment: These huge , brilliant analyses seldom report original results, but carry enormous weight, and are perhaps the strongest evidence of the benefit of nodal radiotherapy.