ADENOCARCINOMA IN FEMALES DETECTED IN SEROUS EFFUSIONS - CYTOMORPHOLOGIC ASPECTS AND IMMUNOCYTOCHEMICAL REACTIVITY TO CYTOKERATIN-7 AND CYTOKERATIN-20

OBJECTIVE: To investigate the usefulness of assessing the immunoreacti vity of cytokeratins 7 (CK7) and 20 (CK20) as well as several cytomorp hologic parameters in effusions with metastatic adenocarcinomas in the search for the primary site of the tumor. STUDY DESIGN: From the file s of the Pathology Department, A. C. Camargo Hospital, we studied cyto logic smears from 73 metastatic adenocarcinomas originally from the br east, 63 from the ovary, 40 from the lung and 32 from the stomach, loo king for morphologic parameters that could have discriminant potential in suggesting the primary site in a routine situation, including intr anuclear inclusions, prominent nucleoli, mitosis, signet-ring cells, p sammoma bodies, nuclear crease, binucleation and multinucleation, papi llary features, acinar profile (including ball cells) and single cells . Immunoreactions were performed with monoclonal antibodies to CK7 (OV -TL 12/30) and CK20 (Ks 20.8) and included morphologic analysis. Both analyses were studied in a blind fashion regarding the primary site of the tumors. RESULTS: Positivity ratios for breast, ovary, stomach and lung cases were 67.6%, 63.5%, 29.7% and 45.5%, respectively, for CK7 and 17.2%, 15.8%, 13.5% and 32.2%, respectively,for CK20. Discriminant analysis of morphologic and immunocytochemical parameters had an erro r rate of 42.9% in recognizing the primary site and a Wilk's lambda of .7290. CONCLUSION: The more efficient parameter with discriminant fun ction was the papillary appearance showed by CK7, which should be used in further studies with a similar scope. The set of parameters used i n this study were insufficient to discriminate the primary site of fem ale adenocarcinomas in effusions with significant accuracy.