Intraoperative examination of the sentinel lymph node for breast carcinomastaging

Intraoperative pathologic examination of the sentinel lymph node (SLN) drai ning a primary breast carcinoma allows an SLN-positive patient to undergo c omplete axillary lymphadenectomy as part of the same surgical procedure. Ho wever the optimal technique for rapid SLN assessment has not been determine d We reviewed our results with imprint cytology, (IC) and frozen section (F S) examination of SLNs from 278 patients. Compared with H&E-stained paraffi n sections, IC and FS had an overall accuracy of 93.2%. The false-reassuran ce rate (false-negative results/all negative results) was 8.4%. It correctl y identified 98% of macrometastases but only 28% of micrometastases. There were no false-positive results. Compared with paraffin-section cytokeratin immunohistochemistry results, the IC-FS false-reassurance rate increased to 25.8%. The false-reassurance rate decreased with smaller primary tumor siz e (TI vs T2/3) and ductal type, smaller diameter of the SLN (less than or e qual to 2.0 cm), and greater pathologist experience. IC combined with 2-lev el FS reliably identifies SLN macrometastases but commonly fails to detect SLN micrometastases. If SLN micrometastasis is used to determine the need f or further Lymphadenectomy, more sensitive intraoperative methods will be n eeded to avoid a second operation.