Cases and Data Collection

We searched the electronic pathology records at 7 tertiary care institutions for biopsy, excision, or surgical resection specimens of cirrhotic livers with mass lesions. Among these specimens were well-defined examples of metastases to liver. As our control population, we selected cases from surgical pathology archives at these institutions of cirrhotic livers without mass lesions in patients who had histologic confirmation of distant metastases at other sites. Because few such control cases were identified in our surgical pathology archives, autopsy archives were also searched. We also developed separate control populations of patients with primary liver neoplasms and cirrhosis, and patients with masses in non-cirrhotic livers. Patient medical records of cirrhotic metastasis cases were reviewed for clinical history (including possible sequelae of cirrhosis), radiologic data (including echocardiogram and ultrasound Doppler results, which were reviewed for evidence of veno-arterial shunting) and laboratory values. This information was also reviewed in the controls with cirrhosis and metastatic disease that did not involve the liver, and in a subset consisting of 10 % of the controls with primary liver tumors and cirrhosis. The study was approved by the Institutional Review Boards at each of the involved institutions.