Diffuse hepatic intravascular carcinomatous embolization resulting in fatal liver failure: a clinicopathologic study of 4 cases.

The authors report four cases in which patients died of acute or fulminant hepatic failure resulting from massive intravascular metastatic carcinomatous embolization, a rarely reported manifestation of metastatic disease. Neoplasms were high grade carcinomas. Tumor emboli were present within portal branches ranging 0.12-2.9 mm in diameter and were free floating or attached to the vascular wall, with or without varying degrees of superimposed organization. In one case, intravascular tumor necrosis was prominent and appeared as granular casts with superimposed dystrophic calcification and/or entrapped foamy histiocytes. There were associated geographical areas of parenchymal (4 cases) and tumor (1 case) ischemic necrosis with a multifocal and regional topographic distribution. An associated predominant pattern of intrasinusoidal tumor infiltration (with or without fibrosis) was present in 3 cases, whereas the fourth case had underlying micronodular cirrhosis, providing ancillary evidence for preexisting altered intrahepatic microcirculation. The literature on fatal hepatic failure resulting from neoplasia is reviewed with a reassessment of its pathobiological significance.