RAT was performed if the SLNs were negative.
Of these, 8 (11.8%) SLNs were positive and 56 (88.2%) SLNs were negative on intraoperative frozen sections.
No further ALND was performed, if SLNs were negative in frozen sections.
Forty-four of the patients in whom all SLNs were negative for tumor, as confirmed by the central laboratory, or in whom no SLNs were detected, also had all non-SLNs negative for tumor (both conditions included as 'true negatives').
Sentinel lymph node biopsy alone, without ALND, was performed exclusively if SLNs were negative in frozen sections and in H&E-stained H&E-stainedin IHC-slidesd slides.
Exclusively, the 200 patients whose SLNs were negative in frozen sections and permanent H&E-stained sections and in IHC staining had SLNB alone without further ALND.
In nine out of 128 patients (7.0%) SLNs were negative in frozen sections, but positive in permanent H&E staining, and in further 15 out of 128 patients (11.7%) SLNs converted positive in IHC staining.
In six patients (2.83%) the NSLN were positive on histology, and in three of them SLN were negative.
Whether the SLN is involved is a highly accurate predictor of overall axillary LN status, and the patient morbidity rate has been reduced by omitting unnecessary axillary lymph node dissection (ALND) when the SLN is negative for metastases (Veronesi et al, 1997; Krag et al, 2010).
If the SLN was negative on the initial H&E section, a second H&E section (approximately 200 microns deeper into the tissue block) and an additional section submitted for immunohistochemical analysis with panmelanocytic cocktail (includes antibodies to detect HMB45, Mart-1, and tyrosinase) were reviewed to evaluate for the presence of SLN metastasis [ 26, 27].
