How would you approach a patient who is s/p mastectomy with only DCIS in the breast and a large positive sentinel node?

If the patient had SLN only (no ALND), I would offer adjuvant radiation extrapolating from AMAROS. While only DCIS in the mastectomy specimen, nodal involvement suggests foci on invasion.

Implant reconstruction may increase the complication profile but would not change my recommendation. Age < 50 wo...

If the only reason to treat is the macromet in one node with no other adverse factors, I would favor ALND to avoid RT, especially to avoid the effect RT on reconstruction.

If the patient is unwilling to have an ALND because of the risk of lymphedema, then an additional treatment to the axilla is need...