“…The primary purposes of NAC are to downstage breast cancers and improve the possibility of breast-conserving therapy in most breast cancers [ [2] , [3] , [4] ]. After preoperative chemotherapy, breast tumors shrink to different extents and show various regression patterns, including pathologic complete response (pCR), unifocal shrinkage, multiple residual foci, main residual disease with satellite foci, stable disease (SD) and progressive disease (PD) [ [5] , [6] , [7] , [8] ]. Among these patterns, unifocal residual disease and pCR favor the adoption of breast-conserving surgery (BCS).…”