Algorithm for immediate cytologic diagnosis of hepatic tumors.

Objective: Immediate cytologic assessment of hepatic lesions can help determine the adequacy of specimens and may yield a preliminary diagnosis. The purpose of this study was to analyze the diagnostic accuracy of on-site cytologic assessment compared with definitive cytologic examination in the detection and correct subtyping of malignant hepatic lesions.
Subjects and Methods: The study population included 472 consecutively registered patients with hepatic nodules who underwent sonographically guided fine-needle aspiration and core biopsies. During on-site cytologic analysis, the pathologist made a preliminary diagnosis of malignancy or negative for malignancy for each nodule. When a malignant lesion was diagnosed, immediate subtyping was attempted.
Results: With immediate cytologic analysis, 280 (80.9%) of 346 malignant nodules were correctly identified without false-positive cases. With immediate subtyping, 113 (68.1%) of 166 cases of hepatocellular carcinoma, 28 (77.8%) of 36 cases of cholangiocarcinoma, and 113 (85.0%) of 133 cases of metastasis were detected.
Conclusion: High diagnostic accuracy for malignancy can be achieved with on-site cytologic evaluation of hepatic tumors. Specific diagnoses of hepatocellular carcinoma, cholangiocarcinoma, and metastasis also can be made on-site in most cases. The absence of false-positive diagnosis of malignancy at on-site cytologic examination may make additional biopsy unnecessary. We propose an algorithm for the cytohistopathologic management of hepatic tumors.