Combined carcinoembryonic antigen and cytopathologic examination in ascites

OBJECTIVE: To investigate use of the combined carcinoembryonic antigen (CEA ) test and cytopathologic examination to improve the diagnosis of neoplasti c vs. nonneoplastic ascites. STUDY DESIGN: The tests were performed prospectively on 130 patients with a scites whose effusions were submitted for cytologic examination. RESULTS: Sixty-seven patients had epithelial tumors, and the cytologic exam ination was positive in 39 (58.2%). The CEA level was greater than or equal to 11.0 ng/mL in 36 patients (53.73%). CEA was helpful in the diagnosis in 18 cases, increasing to 57 (85.07%) the number of positive diagnoses. Eigh t samples of nonepithelial tumors had low levels of CEA. In 55 patients wit h nonneoplasic ascites the cytopathologic examination was negative, but the CEA assay was >11.0 ng/mL in 3 patients. CONCLUSION The cytopathologic examination should be performed in all cases, and the CEA assay should be done in suspected cases of epithelial neoplasi a in which the cytologic examination was negative, there was uncertainty ab out the histologic type of neoplasia, or a diagnosis of nonepithelial neopl asia was made. When ascitic leukocytosis or hepatic failure is present, one should be cautious in interpreting the CEA assay because false positivity can occur.