Guided percutaneous fine needle aspiration of the liver

FNA has become widely accepted as a diagnostic procedure In the detection of primary and metastatic tumors of the liver. However, cytologic smears often show loss of histologic architecture and the differential diagnosis of a well differentiated hepatocellular carcinoma (HCC) from benign lesions is sometimes impossible. It is well known that the usual cytologic criteria for malignancy are not applicable in the diagnosis of liver diseases. Cell blocks prepared from FNA material with preservation of the histological architecture compensate for the disadvantages of cytologic smears and facilitate a more definite diagnosis. In our series, 98 patients had FNA of liver guided by CT (66) or USG (32). Primary Ca of liver predominated (74%), of which (76%) were HCC. Cell block alone enabled a positive diagnosis in 16% of HCCs in our series. With the aid of lipiodol injection, which results in retention of iodized oil in tumor cells, FNA is able to obtain material from small HCC and facilitate early surgery. Fifteen of the 98 patients were given lipiodol injection and subsequent FNA detected HCC in 8 cases. Cytologic and ultrastructural findings related to lipiodol were most florid 2-3 weeks after injection. We found that naked atypical nuclei, multinucleated giant hepatocytes, and a broad trabecular or acinar pattern lined by sinusoidal endothelial cells were the pathognomonic criteria for HCC. To achieve a successful FNA diagnosis, an adequate sample and full understanding of the cytomorphology of liver diseases are essential.