Bilateral inferior vena cava in a patient with lymphoma - Clinical anatomy and embryology

The development of the inferior vena cava (IVC) includes contributions from diverse embryonic venous precursors and involves major cross connections and left-to rightshunting. This complex process is vulnerable to errors. However, congenital malformations of the IVC are reported to be rare. Most of these malformations are accidental findings in chest and abdomen imaging. Anomalies of the IVC are compatible with life but are of major clinical importance. This paper describes a case of bilateral IVC in a male cadaver observed by dissection. The common iliac veins were found to continue superiorly as the IVC and fused together slightly cranial to the level of the origin of the superior mesenteric artery from the aorta. The left IVC received the left gonadal vein and, slightly superior to its union with the renal vein, it received the left suprarenal vein. It fused side-to-side with the left renal vein, crossed to the right side anterior to the aorta and fused with the right IVC to form the common IVC. The embryology and clinical relevance of this anomalous IVC are discussed. Currently there is little emphasis on the clinical implications of IVC anomalies in medical school anatomy and embryology teaching. The most widely used textbooks dismiss vena cava malformations with the indication "they are not common". A lack of knowledge of possible vascular malformations might result in a misinterpretation of the radiologic images of anomalous veins, leading to surgical errors such as bleeding during retroperitoneal lymph node dissection. Anatomy and embryology textbooks need to incorporate the findings that have emerged recently and are summarized here.