Cytokeratin staining for intraoperative evaluation of sentinel lymph nodes in patients with invasive lobular carcinoma.
BACKGROUND
Frozen section and intraoperative imprint cytology (IIC(N)) are 2 methods used for intraoperative pathologic assessment of sentinel lymph nodes (SLNs). The SLN evaluation of patients with invasive lobular carcinoma (ILC) results in a relatively high number of false-negative results using either of these methods. The purpose of this study was to evaluate the added benefits that intraoperative immunohistochemical-cytokeratin staining (I(CK-IHC)) can bring to IIC(N) in the evaluation of SLN in patients with ILC.


METHODS
A total of 59 breast cancer patients with ILC underwent an SLN biopsy evaluated by our standard IIC(N) assessment in addition to I(CK-IHC). The results of IIC(N) with I(CK-IHC) were compared with the final histopathologic assessment consisting of standard hematoxylin and eosin staining and additional cytokeratin staining of nodes.


RESULTS
Intraoperative evaluation of SLN using IIC(N) and I(CK-IHC) correctly diagnosed the nodal status in 45 of 59 (76.3%) patients. On final histopathologic assessment, 31 of 59 (52.5%) patients were found to have positive nodes. Using I(CK-IHC), 17 of these 31 positive cases (54.8%) were detected. Using IIC(N) alone, without the benefit of I(CK-IHC), only 13 of 31 (41.9%) positive cases were detected intraoperatively.


CONCLUSIONS
For patients with ILC, I(CK-IHC) staining in addition to IIC(N) improves accuracy over using IIC(N) alone. In this study, I(CK-IHC) staining demonstrated a 12.9% improvement in the detection of SLN metastases in patients with ILC. Cytopathologists should consider employing I(CK-IHC) staining to evaluate the touch-imprint slides of SLN in ILC patients.
Weinberg
E S
ES
Department of Surgery, H. Lee Moffitt Cancer Center and Research Institute, University of South Florida, 12902 Magnolia Dr., Suite 3157, Tampa, FL 33612, USA.
Dickson
Daniel
D
White
Laura
L
Ahmad
Nazeel
N
Patel
Jayesh
J
Hakam
Ardeshir
A
Nicosia
Santo
S
Dupont
Elisabeth
E
Furman
Ben
B
Centeno
Barbara
B
Cox
Charles
C
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000473:pathology*; D018275:Carcinoma, Lobular / Q000473:pathology*; D005260:Female; D006801:Humans; D007430:Intraoperative Care; D007633:Keratins; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D015203:Reproducibility of Results; D021701:Sentinel Lymph Node Biopsy; D013194:Staining and Labeling
D007633:Keratins