What is the appropriate nodal coverage a invasive ductal carcinoma status post lumpectomy with 50% or more of the SLN biopsied (for example, 2 of 4 SLN) showing micrometastases?

I don't know what 50% or more for SNLN means, as knowing absolute number of nodes is more important as median number of SNLN dissected is usually between 1-2 . The treatment volume in patients with micromets is highly variable across practitioners- from no adjustment of field (based on IBCSG 23-01) ...