Liver metastases: Incidence and histogenesis

Metastases are the most common malignant tumors of the liver. In the files of the Institute of Pathology of the University of Cologne 12,161 liver tissue cases are registered. Of them, 1,357 cases (11.2 %) showed tumors or tumor like masses. Liver metastases of solid tumors were the largest group of the neoplasias with 611 cases (5.0 %) followed by hepatocellular carcinoma (380 cases; 3.1 %). Other entities were rare and include cholangiolar carcinoma (0.5 %), vascular tumors (0.4 %), lymphomas (0.4 %), focal nodular hyperplasias (0.36 %) and liver cell adenomas (0.23 %). Adenocarcinomaa are the largest group of metastases with 400 cases (65.5 %). 48.2 % of this group were metastases of colorectal cancer, 13.5 % of pancreatic cancer, 13 % of breast cancer, 6.2 % of gastric cancer, 4.5 % of lung cancer and 3.7 % of esophageal cancer. Neuroendocrine carcinomas are the second largest group with 16 % of liver filiae. Other entities were rarely found. Metastases in cirrhotic livers are seldom. The gross findings, the histology, the differential diagnosis including immunohistochemistry and the value of the liver biopsy is discussed.