Inferior Vena Cava Syndrome due to Giant Hepatic Cyst After Blunt Trauma

A 78-year-old woman presented with sudden-onset lower extremity edema, abdominal pain, and loss of appetite that developed the day after she fell off her bicycle. Computed tomography showed a simple hepatic cyst, 17 cm in diameter, compressing the inferior vena cava (IVC). Her symptoms resolved following laparoscopic deroofing. Notably, the cyst had remained stable at 12 cm 2 and 4 years prior, without any evidence of IVC compression. Although many guidelines for asymptomatic simple hepatic cysts published to date do not recommend treatment or follow-up regardless of size, our experience suggests the importance of monitoring simple hepatic cysts larger than 12 cm.