Using one-step nucleic acid amplification (OSNA) for intraoperative detection of lymph node metastasis in breast cancer patients avoids second surgery and accelerates initiation of adjuvant therapy

Sentinel lymph node (SLN) analysis is conventionally analyzed using immunohistochemistry and in the case of SLN involvement, justifies a second surgery for axillary lymph node (ALN) resection, thus delaying the initiation of adjuvant therapies. Three hundred and eighty-one patients with early stage breast cancer (BC) were considered in this retrospective study. SLNs were detected using combined radioisotope and dye detection. SLN involvement was analyzed using routine intraoperative One-Step Nucleic Acid Amplification (OSNA) assay, in 100 patients and compared with the conventional histopathology carried out previously in 281 patients. Considering positive SLNs as ‘++’ (CK19 mRNA copy number>5000), ‘+’ (250 < CK19 mRNA copy number