Introduction

Benign adrenal pathology is rare in children¹. Adrenal surgery in children is performed most commonly for neuroblastoma.² Because of the infiltrative nature of neuroblastomas, they are often not suitable for laparoscopic adrenalectomy.³ Nevertheless, more articles, especially from Asia, describe a laparoscopic approach. This may only be recommended when performed by experienced teams and as part of a multidisciplinary program.⁴ Since laparoscopic adrenalectomy was first described in 1991, it has rapidly replaced open adrenalectomy for adrenal pathology in adults.⁵ The advantages of laparoscopic surgery for the adrenal gland are to provide equal to superior exposure of the viscera, diminish soft tissue dissection, and to decrease postoperative pain.⁴ Laparoscopy can also be utilized for adrenal biopsy in nonresectable tumors.^4,7 The purpose of this document is to discuss the workup, medical, and surgical management of adrenal masses in children.

Definition

Adrenal lesions are defined as masses or enlargements in the adrenal gland. The adrenal masses can be functional secreting hormones or nonfunctional. The adrenal glands can also be hyperplastic due to genetic abnormalities. The cortex or the medulla can be involved in the process. Incidental adrenal masses are those that are found when testing is being performed for other reasons and a mass is discovered in the adrenal gland. Adrenocortical tumors constitute less than 0.2% of neoplasms in children and account for about 6% of adrenal tumors in children.⁸ Pheochromocytoma, a tumor of the chromoffin system, accounts for 1% of hypertensive patients.⁹ The most common tumor in children is the neuroblastoma.^9,10

Disclaimer

Clinical practice guidelines are intended to indicate the best available approach to medical conditions as established by systematic review of available data and expert opinion. The approach suggested may not necessarily be the only acceptable approach given the complexity of the health care environment. These guidelines are intended to be flexible, as the physician must always choose the approach best suited to the individual patient and variables in existence at the moment of decision. These guidelines are applicable to all physicians who are appropriately credentialed and address the clinical situation in question, regardless of specialty. Guidelines are developed under the auspices of the International Pediatric Endosurgery Group Surgeons and its various committees, and approved by the Executive Committee. Each guideline is developed with a systematic approach and includes a review of the available literature and expert opinion when published data alone are insufficient to make recommendations. All guidelines undergo appropriate multidisciplinary review prior to publication and recommendations are considered valid at the time of publication. Because new developments in medical research and practice can change recommendations, all guidelines undergo scheduled, periodic review to reflect any changes. The systematic development process of clinical practice guidelines began in 2007 and will be applied to all revisions as they come up for scheduled review, as well as all new guidelines.

Diagnosis

History and physical examination of patients are performed. In patients with clinical signs of functioning masses such as virilization, hirsutism, acne, hypertension, investigations with radiographic and biochemical studies, pheochromocytoma may present with headache, hypertension, and sweating.¹¹ Adrenal masses can be palpated in smaller children or may be found on abdominal scans performed for other problems. Once an adrenal mass is palpated, the workup should include radiographic studies, such as abdominal computerized axial tomography (CT) scans, ultrasounds, magnetic resonance imaging (MRI) studies, and, possibly, metaiodobenzylguanidine (MIBG) scintiscans.^8,9,12 In addition, markers of hormonal activity should be tested, such as vanillymandelic acid (VMA), homovanillic acid (HVA), and urinary or serum catecholamines.

If evidence of functioning adenoma is seen, cortisol and 17-hydroxysteroids are tested. Pheochromocytoma is a functioning neural crest paraganglionic neoplasm, which may arise in the adrenal gland.¹³ For pheochromocytoma, the most sensitive diagnostic modalities are 24-hour urinary and plasma norepinephrine and metanephrines, MRI, and ¹²³ IMIBG scans.¹¹ Congenital adrenal hyperplasia is an inborn error of metabolism characterized by adrenal 21-hydroxylase deficiency.¹⁴ These recommendations are based on class 3 evidence.

Management

Preoperative management depends on the type of adrenal mass identified. Prior to operation, a localizing test such as CT scan, MRI, or MIBG scan are performed. In adults, a mass greater than 15 cm represents a relative contraindication for laparoscopic resection due to limited space availability. In children, an absolute limitation cannot be determined, but should be evaluated individually, based on size of mass relative to size of child.^5,12,15 Other researchers suggest a 5-cm well-defined lesion as a cut-off size for adrenalectomy.¹⁶ Incidentaloma with negative preoperative workup is suitable for adrenalectomy, if the size of the tumor is greater than 5 cm.^10,12,17,18

For patients with pheochromocytoma, a preoperative preparation is required. Once diagnosed with radiographic and biochemical markers, the patients with pheochromocytoma should be treated to block the alpha-receptors with phenoxybenzamine and then correcting the extracellular fluid volume deficit with oral or intravenous fluid.¹² Alphamethyltyrosine, which competitively inhibits tyrosine hydroxylase in the synthesis of catecholamines, can also be used.¹³ Alpha blockade is usually complete after 10–14 days, and beta-blockers, such as propranolol or atenolol, can be added to minimize arrhythmias, if the child has a significant tachyarrhythmia. These recommendations are based on class 3 evidence, mostly from retrospective reviews and case series.

Operative Treatment

For the majority of neuroblastomas, open adrenalectomy remains the mainstay of treatment. For advanced neuroblastoma, open biopsy or laparoscopic biopsy of the mass may be performed. Some teams use a retroperitoneal approach to these tumors, depending on the preoperative imaging. In a group of patients undergoing laparoscopic biopsy, time to feeding and start of chemotherapy could be decreased by using the laparoscopic, compared to the open, approach.⁴ For small early tumors with no evidence of invasion on preoperative studies, laparoscopic resection can be entertained, if the principles of oncologic surgery can be maintained.^4,7 Laparoscopy can also be considered if the neuroblastoma responds to chemotherary.¹⁹ Size greater than 6 cm, enlarged veins, and involved adjacent organs or vessels are relative contraindications to laparoscopic adrenalectomy for neuroblastoma.⁷ As described by Steyaert,¹⁷ retropertoneoscopic resection may be more acceptable for left-sided tumors and laparoscopic for right-sided tumors, but there is no consensus. All adrenal glands have to be extracted by using an endobag. In addition, incidentalinomas are becoming a more common indication for surgery. After preoperative preparation, laparoscopic resection is feasible for the treatment of pheochromocytomas.¹² Laparoscopy is also appropriate for benign tumors and adrenal hyperplasia.¹⁸

The lateral transperitoneal approach offers an efficient working space with excellent exposure. For this method, the patient is placed in a 90-degree lateral decubitus position with the operative side up. The kidney rest is raised and the table is flexed maximally.^5,12,20 Cannulas are inserted below the costal margin from the posterior axillary line to just medial to anterior axillary line.^2,4,12 A retroperitoneal approach can also be used. The patient is placed in the lateral decubitus position. In this approach, the cannulas are placed posteriorly and the retroperitoneal space is defined with dissection before insufflation.^1,2,21 Bilateral adrenalectomy via laparoscopy can be approached anteriorly, but the exposure may not be adequate.³ Repositioning the patient and placing new cannulas may decrease the operative time and improve exposure.¹⁴These recommendations are based on class 3 evidence, mostly from retrospective reviews and case series.

Levels of Evidence

The recommendations for diagnosis and management of patients with adrenal masses are all based on level III evidence. All of the articles are descriptive reviews. Most articles documenting surgical options for children with adrenal masses were descriptive studies of children undergoing operation consisting of level III evidence. Since the advent of laparoscopic adrenalectomy in children, the only article comparing open to laparoscopic surgery was the study by Romano et al.¹⁸ This study compared open to laparoscopic adrenalectomy but was not randomized and case selection was based on the size and nature of the lesion or surgeon comfort with the minimally invasive approach. This was level II evidence.

Summary

Laparoscopic adrenalectomy and adrenal biopsy are technically feasible in children. There are no absolute contraindications to the laparoscopic approach, but for neuroblastomas and other adrenal neoplasms, care must be taken to maintain the principles of cancer surgery. As opposed to adults, there are fewer benign indications for adrenalectomy, but in selected cases, laparoscopic resection of the adrenal is feasible. Both laparoscopic and retroperitoneoscopic approaches are recommended, with the choice being dictated by the experience of the surgeon. Recommendations throughout this guideline are based on class 3 evidence, with a single article demonstrating class 2 evidence, based on a retrospective comparison.

References

1. Allal H, et al. Left retroperitoneoscopic adrenalectomy: About two cases. Pediatr Endosurg Innovat Techn 2003;7: 47–50.
2. Mirallie E, et al. Laparoscopic adrenalectomy in children. Surg Endosc 2001;15:156–160.
3. Kadamba P, Habib Z, Rossi L. Experience with laparoscopic adrenalectomy in children. J Ped Surg 2004;39:764–767.
4. Iwanaka T, et al. Surgical treatment for abdominal neuroblastoma in the laparoscopic era. Surg Endosc 2001;15:751– 754.
5. Miller KA, et al. Experience with laparoscopic adrenalectomy in pediatric patients. J Ped Surg 2002;37:979–982.
6. Stanford A, et al. Surgical management of open versus laparoscopic adrenalectomy: Outcome analysis. J Ped Surg 2002;37:1027–1029.
7. DeLagausie P, et al. Laparoscopic adrenal surgery for neuroblastoma in children. J Urol 2003;170:932–935.
8. Ciftici AO, Senocak ME, Tanyel FC, Buyukpamukcu N. Adrenocortical tumors in children. J Ped Surgery 2001;36: 549–554.
9. Ciftici AO, Senocak ME, Tanyel FC, Buyukpamukcu N. Pheochromocytoma in children. J Ped Surg 2001;36:447–452.
10. Masiakos PT, et al. Is surgery necessary for incidentally discovered adrenal masses in children? J Ped Surg 2004;39: 754–758.
11. Ludwig AD, et al. Recent advances in the diagnosis and treatment of pheochromocytoma in children. Am J Surg 2007;194:792–797.
12. Miller KA, Holcomb GW III. Laparoscoic adernalectomy and esophagomyotomy. Sem Ped Surg 2002;11:237–244.
13. Reddy VS, et al. Twenty-five year surgical experience with pheochromocytoma in children. Am Surg 2000;66:1085–1092.
14. Meyers RL, Grua JR. Bilateral laparoscopic adrenalectomy: A new treatment for difficult cases of congenital adrenal hyperplasia. J Ped Surg 2000;35:1586–1590.
15. Skarsgard ED, Albanese CT. The safety and efficacy of laparoscopic adrenalectomy in children. Arch Surg 2005;140: 905–908.
16. Valla JS, et al. Laparoscopic adrenalectomy in children: Experience of the study group of pediatric abdominal surgery in 16 cases. Pediatr Endosurg Innovat Techn 2001;5: 267–275.
17. Steyaert H, Juricic M, Hendrice C, Lembo MA, Mohaidly Al, Guitard J, Valla JS. Retropertoneoscopic approach to the adrenal glands and retroperitoneal tumors in children: Where do we stand? Eur J Pediatr Surg 2003;13:112–115.
18. Romano P, Avolio L, Martuciello G, Steyaert H, Valla JS. Adrenal masses in children. The role of minimally invasive surgery. Surg Laparosc Endosc Percut Tech 2007;17: 504–507.
19. Al-Shanafey S, Habib Z. Feasibility and safety of laparoscopic adrenalectomy in children: Special emphasis on neoplastic lesions. J Laparoendosc Adv Surg Techn 2008;18: 306–309.
20. Castilho LN, Castilho OA, Denes FT, Mitre AI, and Arap S. Laparoscopic adrenal surgery in children. J Urol 2002;221– 224.
21. Shanberg AM, et al. Laparoscopic retroperitoneal renal and adrenal surgery in children. BJU Int 2001;87:521–524.

This guideline was prepared by the IPEG Standards and Safety
Committee and was reviewed and approved by the Executive Committee
of the International Pediatric Endosurgery Group (IPEG),
November 2009.