OBJECTIVETo determine the diagnostic value of B72.3, BerEP4 and calretinin in differentiating metastatic carcinoma cells from reactive mesothelial cells (RMC) in serous effusions by using immunocytochemical method (ICC), and to investigate the feasibility of ThinPrep (TP) preparation for ICC.

METHODSOne hundred fifty eight serous effusion specimens were examined by ICC on cell block (CB) sections (CB-ICC) using antibodies against of B72.3, BerEP4 and calretinin. Fourty-nine of the samples, ICC on ThinPrep slides (TP-ICC) and CB-ICC were performed concurrently.

RESULTSThe sensitivities of B72.3 and Ber-EP4 for detecting carcimoma cells were 76.9% and 69.2% respectively, and when combined the sensitivity was increased to 89.7%. The sensitivity and specificity of Calretinin for detecting mesothelial cells were 90.9% and 87.2% respectively. The sensitivity of B72.3 in differentiating cancer cells from reactive mesothelial cells by CB-ICC and TP-ICC was 78.9% and 68.4%. It was 78.9% and 68.4% of BerEP4 respectively. No statistical significance was observed between CB-ICC and TP-ICC in differentiating metastatic carcinoma cells from reactive mesothelial cells.

CONCLUSIONThe combination of antibodies of B72.3, Ber-EP4 and calretinin is quite helpful as an auxiliary in differentiating metastatic carcinoma cells from reactive mesothelial cells. ThinPrep preparation slides may effectively replace the cell block sections for ICC in differential diagnosis of serous effusions.