Intraoperative touch preparation for sentinel lymph node biopsy: A 4-year experience

Background: The optimal technique for intraoperative pathologic examination of sentinel lymph nodes (SLNs) is still controversial. Recent small series report sensitivity between 60% and 100% for various techniques. The aim of this study was to evaluate our long-term experience with touch preparation cytology (TPC) and frozen section (FS) in the intraoperative examination of SLNs for breast cancer. Methods: A total of 247 patients with operable breast cancer underwent an SLN biopsy for staging of the axilla. The SLN was identified by ^99mTc-labeled sulfur colloid unfiltered dye, blue dye, or both and dissected, and then intraoperative TPC or FS and permanent section, or both, were performed. Results: A total of 479 SLNs were submitted for TPC and permanent hematoxylin and eosin. A total of 68 SLNs were positive by hematoxylin and eosin; 65 SLNs were positive by TPC, with a false-negative rate of 5.8%. The sensitivity for TPC was 94.2%, with a false-positive rate of 0.2%. A total of 165 SLNs were submitted for FS, with a sensitivity of 85.7% and a specificity of 98.6%. The false-positive rate was 1.4%, with a false-negative rate of 15.8%. Conclusions: In a large series, TPC is as accurate as FS but is simpler and faster in the detection of intraoperative metastasis in SLNs for breast cancer.