Left Adrenal Venous Drainage into the Inferior Vena Cava in a Pheochromocytoma Patient with Ectopic Pelvic Kidney

In this report, we describe a very rare variant adrenal venous anatomy in a left-sided pheochromocytoma case with left adrenal vein draining into the inferior vena cava (IVC). A 66-year-old female with an incidentally discovered left adrenal mass was referred to our clinic for further diagnostic work up. She had hypertension for the past three years. Abdominal magnetic resonance imaging which has been performed for essential thrombocytopenia revealed a left adrenal mass. She was diagnosed as pheochromocytoma by further laboratory workup. Pre-operative imaging with computed tomography (CT) angiography showed that left kidney was ectopically localized in pelvis, and left adrenal vein was draining directly into the IVC. A laparoscopic transabdominal left adrenalectomy was performed. Final pathology result was consistent for pheochromocytoma. Variant adrenal venous anatomy is rare. There are only few case reports on patients with left adrenal vein draining into the IVC. Although there are handful of autopsy studies, these studies were performed on normal adrenal glands. The number of clinical reports on variant adrenal venous anatomy is limited. Clinical studies revealed that most commonly seen variant adrenal venous anatomy was number based and were associated with larger tumor size and pheochromocytoma. Pre-operative CT imaging could be used to improve the identification of venous anatomy. In this report, we present a very rare case of an adult patient with left ectopic kidney who had undergone laparoscopic adrenalectomy for left adrenal pheochromocytoma and had left adrenal vein draining into the IVC. To the best of our knowledge, it is a first in the literature. Pre-operative CT imaging identified the variant adrenal venous anatomy in this patient.