Proliferative index using Ki67 index in reactive mesothelial versus metastatic adenocarcinoma cells in serous fluid

Background:The cytological diagnoses of serous effusions are usually made by routine cytomorphologywith certainty. However, overlapping cases sometimes exist between reactive mesothelial andadenocarcinoma cells.We tried to evaluate the diagnostic utility of proliferative index usingki67 monoclonal antibody in distinguishing between reactive mesothelial cells andadenocarcinoma in serous effusions.Materials and Methods:Paraffin blocks and H&E stained slides of peritoneal and pleural fluid cell blocks wereretrieved from cytology archive of Alzahra Hospital, Medical University of Isfahan,between2006 and 2010. From among 1025 slides which were screened to ascertain their appropriatediagnoses.Among of these 80 paraffin embedded cell blocks,40 cases for each reactive andadenocarcinoma groups were selected. Proliferative index was calculated by using Ki 67monoclonal antibody against nuclear proteins.Results:The mean age of the patients in the reactive mesothelial and adenocarcinoma groups were60.58 and 58.45 years, respectively.The gender distribution for malignant group included 23cases (%57.5) female and 17 cases (42.5%) male. This ratio for reactive group included 14cases (35%) and 26 cases (65%). The mean of ki67 index in adenocarcinomatous cells was:17.15 (SD=15.11) and in reactive mesothelial cells was: 3.58 (SD= 3.59) (p=0.001). Themean of ki67 index according to serousal spaces were included: pleura: 10.56 (SD= 13.06)and peritoneum: 10.03 (SD= 12.78), (p=0.9).Conclusion:Ki67 index is useful immunostaining panel for differentiation of mesothelial andadenocarcinoma cells in malignancy like ovarian carcinoma that sometimes mimicsmesothelial morphology.

کلیدواژه ها:

Ki67 antibody ، mitosis ، adenocarcinoma cell ، reactive mesothelial cell ، serous effusion