Undifferentiated embryonal sarcoma in adult liver.

Undifferentiated embryonal sarcoma (UES) is the third most common primary malignant liver tumor in children, following hepatoblastoma and hepatocellular carcinoma. UES of the liver was first named by Stocker and Ishak in 1978,1 and the majority of patients at the time ranged from 6 to 10 years of age. A recent review of the literature showed only 70 cases of UES in adults reported worldwide in 2008.2 This rare presentation is especially true for adults aged >60 years with only 14 cases of UES reported in this population until now.3,4,5,6,7 In Korea, eight cases of UES in adults have been reported: five cases were in women and four cases were in people older than 60 years.5,6,7,8 We present a new case of adult UES of the liver arising in a 67-year-old man. Like pediatric UES, the adult tumor has an unclear pathogenesis and poor prognosis.