E-cadherin and calretinin as immunocytochemical markers to differentiate malignant from benign serous effusions.
OBJECTIVE
To investigate the expressions of E-cadherin and calretinin in exfoliated cells of serous effusions and evaluate their values in distinguishing malignant effusions from benign ones.


METHODS
Fresh serous effusion specimens were centrifuged and exfoliated cells were collected. Cells were then processed with a standardized procedure, including paraformaldehyde fixation, BSA-PBS solution washing and smears preparation. E-cadherin and calretinin were detected by immunocytochemistry (ICC).


RESULTS
In the exfoliated cells of serous effusions, most of carcinoma cells only expressed E-cadherin, and most of mesothelial cells only expressed calretinin, and benign cells (lymphocytes and granulocytes) did not express either of them. For E-cadherin, 85.7% (30/35) of malignant effusions and 8.1% (3/37) of benign fluids were ICC-positive (P<0.001). The sensitivity of E-cadherin ICC in the diagnosis of malignant effusions was 85.7%, specificity 91.9%, and diagnostic rate 88.9%. For calretinin, 94.6% (35/37) of benign effusions and 11.4% (4/35) of malignant effusions were ICC-positive (P<0.001). The sensitivity of calretinin ICC in the diagnosis of benign effusions was 94.6%, specificity 88.6%, and diagnostic rate 91.7%. For diagnosis of benign and malignant effusions by combining E-cadherin ICC and calretinin ICC, the specificities were up to 100% and 97.1%, respectively.


CONCLUSIONS
E-cadherin ICC and calretinin ICC are sensitive and specific in differential diagnosis of benign and malignant serous effusion specimens and specificities are evidently improved when both markers are combined.
Digestive Disease Institute of Jiangxi Medical College, Nanchang 330006, Jiangxi Province, China.
Dong-Nan
DN
He
Hua-Sheng
HS
Zhu
Kun-He
KH
Zhang
Wen-Jian
WJ
Jin
Wei-Ming
WM
Zhu
Ning
N
Li
Jie-Shou
JS
Li
D000293:Adolescent; D000328:Adult; D000368:Aged; D001202:Ascitic Fluid / Q000473:pathology*; D015820:Cadherins / Q000032:analysis*; D064032:Calbindin 2; D002462:Cell Membrane / Q000473:pathology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D008875:Middle Aged; D016066:Pleural Effusion, Malignant / Q000473:pathology*; D015203:Reproducibility of Results; D064030:S100 Calcium Binding Protein G / Q000032:analysis*; D012680:Sensitivity and Specificity
C576764:CALB2 protein, human; D015820:Cadherins; D064032:Calbindin 2; D064030:S100 Calcium Binding Protein G