Coelomic fat ectopia in the liver.

Abstract

We describe a pedunculated, mesothelial-covered liver mass contained in a mesothelial-lined sac. Microscopically, the mass was composed of mature adipose tissue that contained thick-walled arteries and large veins, fibrous tissue, and numerous bundles of smooth muscle. The lesion was thought to represent ectopic coelomic mesenchyme originally destined to form omentum or mesentery. The existence of this entity suggested that previously reported cases of hepatic adipose tissue masses (lipomas) might also have derived from ectopic coelomic mesenchyme. Along with the mesenchymal lesion in the liver, an unclassifiable mesenchymal tumor was present in the cerebellum. Whether the coexistence of the two mesenchymal tissue masses was fortuitous, or related, could not be determined from this solitary case.