Left adrenal venous drainage into the inferior vena cava in a pheochromocytoma patient with ectopic pelvic kidney

doi:10.21203/rs.3.rs-1594569/v1

Download PDF

Research Article

Left adrenal venous drainage into the inferior vena cava in a pheochromocytoma patient with ectopic pelvic kidney

https://doi.org/10.21203/rs.3.rs-1594569/v1

This work is licensed under a CC BY 4.0 License

Version 1

posted

You are reading this latest preprint version

Purpose

To 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).

Case Report

A 66-year-old female with an incidentally discovered left adrenal mass was referred to our clinic for further diagnostic work up. She had a 3-years history of hypertension.

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. Preoperative 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.

Discussion

Variant adrenal venous anatomy is rare. There are only a 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 were number based and were associated with larger tumor size and pheochromocytoma. Preoperative CT imaging could be used too improve the identification of venous anatomy.

Conclusion

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 tumor and had left adrenal vein draining into the IVC. Preoperative CT imaging identified the variant adrenal venous anatomy in this patient.

adrenal tumors

left adrenal vein

adrenal vein anomalies

pheochromocytoma

Minimally invasive adrenalectomy has become the mainstay treatment for adrenal diseases [1]. Apprehensive knowledge of the anatomy prior the surgery should be obtained on case-by-case basis to construct a proper dissection plan. The textbook venous anatomy for each adrenal gland is described as a single vein draining directly into vena cava on the right side, and a left adrenal vein joining with inferior phrenic vein and then draining into left renal vein on the left side. However, variations of these patterns have been reported in case reports, clinical and cadaveric studies [2]. In majority of patients, kidneys and adrenal glands are anatomical neighbors. In the case of renal agenesis or ectopy, most patients’ adrenal glands lie in its original anatomical location [3]. In this case report, we present an anomalous left adrenal venous drainage into the inferior vena cava (IVC) in an adult patient with a left ectopic pelvic kidney and a left adrenal tumor which previously has been described once in the literature [4].

A 66-year-old woman with a 3-year history of essential thrombocytosis (ET) and hypertension has been referred to our clinic after the incidental detection of a 5 cm left adrenal mass on abdominal magnetic resonance imaging (MRI) performed for ET surveillance. Laboratory results revealed that serum sodium and potassium levels were within normal range. The results of further laboratory assays were as the following; serum aldosterone level: 134.6 ng/dL (Range: 70–300), plasma renin activity: 1.33 ng/mL/hr (range: 0.1–6.56) and spot aldosterone-to-renin ratio: 10.1. Suppression test with 1 mg dexamethasone resulted in 08.00 and 08.30 AM cortisol levels of 1.05 and 1.11 µg, respectively (range: 4.8–19.5). A 24 hours urinary analysis revealed metanephrine level of 4859 µg/24hr (range: 30–350), ~ 14 times the upper limit of normal (ULN), normetanephrine level of 1622 µg/24hr (range: 50–650 ), ~ 3 times the ULN. Vanillylmandelic acid level of 13.7 mg/24hr (range: 1.6–7.3 ), ~ 2 times the ULN.

T2-weighted MRI images on left adrenal gland revealed a 51x52 mm hyperintense nodule with rim contrast enhancement in its original anatomic position. The patient was medically treated with phenoxybenzamine, diltiazem, doxazosin preoperatively for 3 weeks to ensure the adequate alpha and beta blockage has been sustained. Abdominal triphasic computed tomography angiography (CTA) showed that left kidney was ectopically localized in pelvis, and left adrenal vein was draining directly into the inferior vena cava (IVC) posterior to the aorta (Fig. 1).

She was taken into the operating room for a laparoscopic transabdominal left adrenalectomy. The patient was placed in right-lateral decubitus position. Abdominal incision was made in left anterior axillary line left of umbilicus and 10 mm port was placed with open (Hasson) approach. Subsequently, two more 10 mm ports were placed in subcostal left anterior and mid axillary lines respectively. Left paracolic gutter dissection was performed with monopolar hook energy device and a vessel sealer. Splenic flexure was taken down and left kidney was not visualized. A 5 cm left adrenal was seen and surrounding fatty tissue was dissected off the mass without interrupting its capsule. The left adrenal vein draining into the IVC was visualized and clamped with hemostatic clips proximally and distally (Fig. 2). The vein was then cut with scissors and the specimen was extracted using and endoscopic retrieval bag. Following hemostasis, a drain was left in place and operation was finalized without any intraoperative complications. The patient was normotensive during the procedure and followed up in intensive care unit (ICU) without any postoperative complications. Patient was started on regular diet 6 hours after the operation. The drain was removed on postoperative day 1. The patient was discharged on postoperative day 3 and remained normotensive during her postoperative course. Final histopathology of the adrenal specimen was consistent with pheochromocytoma.

The identification of adrenal vein is very important for diagnosis and treatment of adrenal disease. Bilateral venous sampling can be used to differentiate a unilateral adenoma from bilateral hyperplasia. Minimally invasive adrenalectomy requires identification and ligation of adrenal veins [1]. Therefore, variations of adrenal venous anomaly can present a challenge during diagnosis and surgery. Right adrenal vein most commonly drains into posterolateral the IVC while left adrenal vein drains into left renal vein .

The data on anatomical variations of adrenal veins is scarce. Historically, studies performed on cadavers reported higher rate of variations on the right side: right adrenal vein draining into inferior hepatic vein, right renal vein, or combination of all three [5]. On the left side, there are a few variants and are usually accompanied by anatomical anomalies of kidneys and renal veins [6]. If there is a duplicate of left renal veins, left adrenal vein drains into anterior renal vein as described by Field et al [7]. If the renal vein is retro-aortic, left adrenal vein can be seen draining directly into the IVC as described by Stack et al [8]. It can also drain into left lumbar veins or azygos-hemiazygos system [7]. Majority of patients with renal agenesis and ectopia, will have adrenal glands in its original anatomical position [3]. Therefore, the left adrenal vein would retain its connection to the IVC and drain directly into it. Kenney et al reports an anomalous left adrenal vein draining directly into the IVC in a 47-year-old male with bilateral renal ectopia and left adrenal adenoma [4]. Similarly, El-Sherief et al. describes a left adrenal vein draining directly into the IVC in a one-year-old child with multiple congenital malformations and aplastic left kidney [9]. In our case, the patient had a congenital pelvic ectopia of the left kidney with left adrenal gland in its original anatomic location. The abdominal CT angiography revealed that the patient’s adrenal tumor was draining directly to the IVC behind the aorta.

In a study conducted by Scholten et al, 546 consecutive laparoscopic adrenalectomies for anatomical variants of adrenal veins were analyzed. They reported 28 anomalies on the left side (%9) of which only 4 are related to location-based variations. Patients with variant anatomy had more pheochromocytomas. Mean operative time and estimated blood loss was higher for the variant anatomy group [2].

In a more recent study by Sun et al, 303 consecutive minimally invasive adrenalectomies were studied. Variant anatomy was detected in 20.5% and they were associated with increased tumor size, larger adrenal veins and pheochoromocytomas. Similar to previous study number base variations were more common than location based ones. Most common location based left adrenal anomaly was accessory adrenal vein draining into left inferior phrenic vein. No patients with left ectopic kidneys or drainage of left adrenal vein into the IVC was seen. Variant anatomy was also associated with increased blood loss, more need for transfusion, longer operative time and postoperative stay, overall associated with worse surgical outcomes [10].

The minimally invasive surgery for adrenal tumors provides better visualization of relevant anatomy although controlling bleeding may provide difficult with massive intraoperative hemorrhage [1]. Traction injury of adrenal veins can occur during dissection therefore preoperative assessment of vascular anatomy with imaging studies is crucial to construct a proper dissection plan which can predict and prevent major complications [1].

We presented a case with an anomalous left adrenal vein drainage directly into the IVC. Although left adrenal venous anomalies are rare, they can be seen in patients with renal anomalies. Preoperative assessment of vascular anatomy should be considered in all patients with adrenal tumors.

Ethical board of Istanbul University Istanbul Faculty of Medicine has approved the conducted study. The patient has been informed and has consented for publication. The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request. No funding was received and no competing interests exist among authors. B.S. and A.Y.I. wrote the main manuscript. A.P. prepared the figures. F.T., Y.G.S., I.C.S. and N.A. reviewed the manuscript.

Al-Thani H, Al-Thani N, Al-Sulaiti M, Tabeb A, Asim M, El-Menyar A. A Descriptive Comparative Analysis of the Surgical Management of Adrenal Tumors: The Open, Robotic, and Laparoscopic Approaches. Front Surg. 2022;9:848565. Epub 2022/03/22. doi: 10.3389/fsurg.2022.848565. PubMed PMID: 35310427; PubMed Central PMCID: PMCPMC8927071.
Scholten A, Cisco RM, Vriens MR, Shen WT, Duh QY. Variant adrenal venous anatomy in 546 laparoscopic adrenalectomies. JAMA Surg. 2013;148(4):378–83. Epub 2013/05/30. doi: 10.1001/jamasurg.2013.610. PubMed PMID: 23715888.
Ashley DJ, Mostofi FK. Renal agenesis and dysgenesis. J Urol. 1960;83:211–30. Epub 1960/03/01. doi: 10.1016/s0022-5347(17)65695-7. PubMed PMID: 13794746.
Kenney PJ, Keller FS, Koehler RE. Functional adrenal disease: radiologic evaluation in a patient with anomalous kidneys. AJR Am J Roentgenol. 1986;147(2):289–90. Epub 1986/08/01. doi: 10.2214/ajr.147.2.289. PubMed PMID: 3487945.
Sèbe P, Peyromaure M, Raynaud A, Delmas V. Anatomical variations in the drainage of the principal adrenal veins: the results of 88 venograms. Surg Radiol Anat. 2002;24(3–4):222-5. Epub 2002/10/11. doi: 10.1007/s00276-002-0021-x. PubMed PMID: 12375078.
Saadi A, Mokadem S, Chakroun M, Hermi A, Boussaffa H, Ayed H, et al. A cadaveric anatomical study: anatomy and anatomical variations of left adrenal vein. Surgical and Radiologic Anatomy. 2022. doi: 10.1007/s00276-022-02930-x.
Field S, Saxton H. Venous anomalies complicating left adrenal catheterization. Br J Radiol. 1974;47(556):219–25. Epub 1974/04/01. doi: 10.1259/0007-1285-47-556-219. PubMed PMID: 4824554.
Stack SP, Rösch J, Cook DM, Sheppard BC, Keller FS. Anomalous left adrenal venous drainage directly into the inferior vena cava. J Vasc Interv Radiol. 2001;12(3):385–7. Epub 2001/04/05. doi: 10.1016/s1051-0443(07)61922-8. PubMed PMID: 11287520.
El-Sherief MA. Adrenal vein catheterization. Anatomic considerations. Acta Radiol Diagn (Stockh). 1982;23(4):345–60. Epub 1982/01/01. doi: 10.1177/028418518202300402. PubMed PMID: 7158398.
Sun F, Zhuo R, Ma W, He H, Ye L, Xu D, et al. Retrospective analysis of variant venous anatomy in 303 laparoscopic adrenalectomies and its clinical implications. J Surg Oncol. 2019;119(6):801–6. Epub 2019/01/31. doi: 10.1002/jso.25364. PubMed PMID: 30697735.

No competing interests reported.

Download PDF

Version 1

posted

You are reading this latest preprint version

Left adrenal venous drainage into the inferior vena cava in a pheochromocytoma patient with ectopic pelvic kidney

Status:

Version 1

Abstract

Figures

Introduction

Case Report

Discussion

Conclusion

Declarations

References

Additional Declarations

Status:

Version 1