The Role of Cytology in the Diagnosis of Metastatic Hepatocellular Carcinoma

The diagnosis of primary hepatocellular carcinoma (HCC) in high risk patients, such as those with chronic hepatitis B or C with/without cirrhosis of the liver, can be made with relevant image studies alone; however, morphologic confirmation by cytology or histopathology is essential to the diagnosis of metastatic HCC because the treatment of the latter differs from that of primary extrahepatic malignancy. Although both cytology and histopathology are important tools in the diagnosis of malignancy, histopathology almost always plays a confirmatory and pivotal role, and also a gold standard in cyto-histological correlation. We present two patients of metastatic HCC to rare sites; endobronchus in one, and neck lymph nodes, face and the abdominal wall in the other. Repeated bronchial biopsy in the first patient and excisional biopsy from the metastatic sites of the second patient failed to make a conclusive diagnosis of metastatic HCC. However, bronchial brushing in the first patient and fine needle aspiration cytology from the respective metastatic sites of the second patient consistently showed characteristic HCC features and provided clinicians with the rationale for ongoing treatment. The diagnostic issues and possible pitfalls are discussed. Cytology and histopathology appear equipollent; sometimes cytology can play a diagnostic role when histopathology fails its expected role in this scenario.