Absence of the retrohepatic inferior vena cava: what the surgeon should know.

Anomalies of the inferior vena cava are rare and can easily be misdiagnosed if one is not aware of such variants. We report a case of a 57-year-old patient that had a percutaneous CT-guided biopsy of what was considered to be enlarged pericaval lymph nodes. This occurred because of the poor technique of the CT scan and the unawareness of such a condition. These changes were related to a proximal varicele of an absent, retrohepatic inferior vena cava. There was an extensive collateral network with filling of large azygos and hemiazygos veins draining through the posterior mediastinum into the superior vena cava. This case emphasizes the importance of correctly identifying vascular anomalies before the initiation of biopsy attempts in order to prevent the risk of major complications that could arise during such biopsy.