Population-based study of prognostic value of nodal status before and after neoadjuvant chemotherapy in breast cancer

In breast cancer, neoadjuvant chemotherapy (NAC) can downstage the nodal status, and can even result in a pathological complete response. A population-based study in The Netherlands evaluated the prognostic effect of nodal status before and after NAC. The study included breast cancer patients receiving NAC between 2005 and 2019. The 5-year OS of the cN0-ypN0 subgroups was statistically significant better than that of the cN+yp0-subgroup (94.4% versus 90.1%; p<0.0001). The figure shows that in cN0 as well as cN+ disease, ypN+ had a statistically worse 5-year OS compared to ypN0. For HR+ HER2-, HR+ HER2+, HR- HER2+, and TNBC, respectively, 5-year OS in the cN0ypN+ subgroup was 89.7%, 90.4%, 73.7%, and 53.6%, and in the cN+ypN+ subgroup 84.7%, 83.2%, 61.4%, and 48.8%. The authors conclude that this study suggests that among breast cancer patients receiving NAC, both cN status and ypN status as well as molecular subtype have prognostic value.