How would you approach a patient with T1aN1 breast cancer when the ER/PR/HER2 status cannot be determined by IHC?

This situation is unusual. Was the 2mm on the diagnostic biopsy and no other cancer found on the resected specimen? I would wonder if there is another undetected invasive component still in the breast if they did a lumpectomy and slnb. If the 2mm focus was depleted for IHC, I would try to test recep...