Multiple necrotic nodules of the liver simulating liver metastasis

A 70-year-old man was referred to our hospital due to anemia and elevated serum tumor marker levels. He had advanced colon cancer, and hepatic lesions were found incidentally. On ultrasonography (US) and computed tomography (CT), the hepatic lesions had a maximum diameter of 20 mm and were located in Couinaud's segments V, VI, VII, and VIII, which suggested liver metastasis. On early- and late-phase CT during hepatic arteriography (CTHA), all of the lesions had rim enhancement. On early-phase CT during arterioportography (CTAP), all of the lesions were seen as nodules with an irregular perfusion defect, and on late-phase CTAP, all the lesions gradually became iso-dense, and their shape and size changed. Based on the CTAP findings, these lesions were thought to be fibrotic tumors. Partial resection of the liver (including the lesions in Couinaud's segments V and VIII) was done. Histological examination revealed that the lesions were necrotic nodules. Thus, CT angiography (CTHA and CTAP) was useful for identifying necrotic nodules, because their appearance on this modality is different from that of liver metastases.