Detection of cancer cells in effusions from patients diagnosed with gynaecological malignancies - Evaluation of five epithelial markers

The detection of malignant cells in pleural, peritoneal, and pericardial fl uids of cancer patients marks the presence of metastatic disease and is ass ociated with a grave prognosis. We evaluated five epithelial markers for th e detection of cancer cells in 94 fresh pleural, peritoneal and pericardial effusions. Eighty-four of the samples were regarded as adequate for analys is after evaluation of cytological smears, including 61 samples from patien ts known to have gynaecological neoplasms. The other 23 samples were from p atients with various non-gynaecological malignancies or tumours of unknown origin. Our control cases were 10 fallopian tubes not affected by any malig nancy and 12 malignant mesotheliomas. Cell blocks from all cases were stain ed for CA-125, BerEP4, carcinoembryonic antigen (CEA), BG8 (Lewis Y blood a ntigen), and B72.3 (TAG-72). Fifty-one of 84 cases were diagnosed as malign ant or suggestive of malignancy in cytological smears and/or cell block sec tions. However, staining for epithelial markers highlighted the presence of malignant cells in 7 additional cases. When membrane staining was evaluate d, the sensitivity of the markers studied in detecting malignant cells was as follows: CA-125: 88%, BerEP4: 78%, CEA: 26%, BG8: 86%, B72.3: 79%. Membr ane positivity for CEA, B72.3 and BerEP4 was not detected in reactive mesot helial cells. However, membranous staining in mesothelial cells was evident in 13% and 31% of cases with the use of BG8 and CA-125, respectively. Weak cytoplasmic staining for CEA was observed in mesothelial cells in 2 cases. When Ber-EP4, B72.3, and BG8 staining results in cancer cells were combine d, the following sensitivity levels were observed: BG8+B72.3: 91%; BG8+Ber- EP4: 90%; B72.3+Ber-EP4: 93%; BG8+Ber-EP4+B72.3: 95%. The detection of mali gnant cells in effusions is facilitated by the use of immunocytochemistry u sing a wide panel of antibodies. BerEP4 and B72.3 appear to be the best mar kers when both sensitivity and specificity are considered, followed by BG8, while CEA and CA-125 have a limited role in the detection of metastases fr om gynaecological tumours owing to the low sensitivity of the former and th e low specificity of the latter. Analysis of all staining results should be based on a thorough morphological examination.