A Rare Case of Hepatic Echinococcus granulosus Infection Diagnosed by Autopsy in Japan

A 20-year-old Japanese woman moved to Manchuria and worked as a sheep farmer for 5 years. Subsequently, she returned to Japan. In her 80s, abdominal ultrasound and computed tomography revealed a large tumor that had spread to both lobes of the liver. The tumor was encapsulated, and partial calcification and multiple cysts within a large cyst (honeycomb pattern) were observed. Serological tests for echinococcosis showed that the Echinococcus-specific antigen was positive, but the antigen characteristic of E. multilocularis was negative. We herein report a case of E. granulosus infection diagnosed more than 60 years after the initial infection.