Open Adrenalectomy 

Updated: Apr 30, 2019
Author: Peter P Stuhldreher, MD; Chief Editor: Kurt E Roberts, MD 

Overview

Background

Although laparoscopic surgery has become the treatment of choice for the majority of incidentally detected adrenal masses, open adrenalectomy still plays an important role in the armamentarium of adrenal surgeons.[1, 2]

Adrenal surgery has a long history, with the first planned adrenalectomy performed in 1914 by Sargent.[3] Mayo performed the first flank approach for pheochromocytoma in 1927, though at the time of surgery, he was unaware of the full disease process involved. Through the early to mid-1900s, multiple changes in surgical approaches to the adrenal gland were developed to augment several posterior and anterior approaches. For decades, little change to adrenal surgery was seen, until the first laparoscopic adrenalectomy was described by Gagner in 1992.[4]

Increasing use of imaging technologies, such as computed tomography (CT) and magnetic resonance imaging (MRI), for aid in diagnosis of other conditions has led to increased diagnosis of adrenal masses.

The incidence of these incidentally noted adrenal masses has been estimated to be around 5%.[5, 6, 7, 3, 8] Autopsy studies have supported this estimation, showing the incidence of adrenal masses found at autopsy also to be in the range of 3-5%.[6, 3, 9] Furthermore, studies of hospital discharges showed a 43.4% increase in adrenalectomy rates from 1988 to 2000.[8, 10] With increasing diagnosis and treatment of adrenal masses, optimization of cure and minimization of morbidity become particularly important.

Indications

Indications for adrenalectomy may seem straightforward at first. However, with the increasing rates of diagnosis of asymptomatic and likely benign adrenal masses, disagreements regarding optimal management remain.[11]

Masses larger than 6 cm have a rate of adrenocortical carcinoma of 25% and should be managed surgically.[9]  Masses smaller than 4 cm may be safely observed because their rate of adrenocortical carcinoma is 2%.[9]

Size categories, however, do not alter management for hormonally active lesions; these should also be managed with surgical excision in most cases. The adrenal gland can be a common site for metastases, and thus, patients with known primary malignancies should be managed according to guidelines for the primary malignancy by stage and grade. For example, the adrenal gland is a common site for synchronous or metachronous metastasis from renal cell carcinoma; surgical excision can frequently offer primary cure in conjunction with nephrectomy.[12]

Surgical excision is indicated for the following adrenal pathologies:

  • Conn syndrome
  • Cushing syndrome
  • Pheochromocytoma
  • Large myelolipoma
  • Metastatic tumors
  • Adrenocortical carcinoma [13]
  • Neuroblastoma (pediatric population)

The choice of approach will depend on the size and location of the mass, the possibility of malignancy, and the surgeon's experience with the different techniques. The open approach to adrenalectomy is considered the gold standard for masses suspected of being adrenal carcinoma.[3, 14]

In addition, open adrenalectomy is the treatment of choice for patients in whom laparoscopic surgery is contraindicated. A patient's inability to undergo pneumoperitoneum is an absolute contraindication for laparoscopy. Multiple previous abdominal operations and obesity remain relative contraindications for laparoscopy.

Contraindications

Absolute contraindications for adrenal surgery of any sort include the following:

  • Uncorrected coagulopathy
  • Poor cardiac or pulmonary function

In cases of widely metastatic disease with a concomitant adrenal mass, tissue diagnosis should be obtained before the decision is made to proceed with adrenalectomy because primary adrenal carcinoma is rare.

Technical Considerations

Anatomy

The adrenal glands are paired glands superior to the kidneys bilaterally (see the image below) that reside within a separated layer of Gerota fascia, and they provide multiple functions in the body. (See the image below.)

Left and right adrenal glands. Left and right adrenal glands.

The outer layer (cortex) of the gland contributes to homeostasis via its endocrine function, whereby it secretes cortisol, aldosterone, and dehydroepiandrosterone (DHEA). These hormones play pivotal roles in regulating salt and water balance and, in the case of DHEA, add virilization hormones to the hormonal milieu. The inner layer (adrenal medulla) is derived from neural crest cells and is important in the sympathetic regulation of the body by secreting norepinephrine. Several disorders of adrenal metabolism are known to involve hypersecretion of these different molecules.

For more information about the relevant anatomy, see Suprarenal (Adrenal) Gland Anatomy.

Procedural planning

Before operative intervention, treatment for appropriate coagulopathies and for hormonal excess should be instituted. Serum potassium levels should be corrected in hyperaldosteronism, and hypertension control should be initiated.

If cortisol excess is severe, inhibition of cortisol with ketoconazole, mitotane, or metyrapone should be considered. In addition, good glucose control is necessary, and operative replacement of steroids is indicated; the hypothalamic-pituitary-adrenal axis for the normal contralateral adrenal gland will remain suppressed for some time after removal of the abnormal adrenal tissue.

For pheochromocytoma, initiation of alpha blockade with either phenoxybenzamine or prazosin is an absolute necessity to protect the patient from the sympathetic surges possible with manipulation of the mass during surgery. For the same purpose, some authors have advocated preoperative use of calcium-channel blockers. In addition, vascular volume reexpansion is often necessary because of volume contraction with hypersympathetic states.

Outcomes

The outcomes of open adrenalectomy vary with the pathology of the disease process, and morbidity changes according to the approach chosen. Approaches that limit access to the peritoneum greatly decrease the rates of postoperative ileus; however, vascular control is often difficult.

The posterior lumbodorsal approach is also associated with high rates of neuromuscular morbidity, including chronic pain (14%), laxity in flank muscles (30%), and flank numbness (10%).[15]

With adrenalectomy alone, roughly 35% of patients with hyperaldosteronism no longer require medications for hypertension.[16]

Outcomes of adrenalectomy for adrenocortical carcinoma are generally poor because this disease tends to present at an advanced stage. A large retrospective review from MD Anderson Cancer Center reported an overall survival of around 58%, with 86% of these cases undergoing adrenalectomy.[17]

Other reports cited a 5-year survival rate in the area of 33%.[17]  When stratified for stage, 5-year survival is 20-45% for stage I adrenal tumors, 12.5-57% for stage II adrenal tumors, 5-18% for stage III adrenal tumors, and 0% for stage IV adrenal tumors.[18]  The most significant predictors of outcome after adrenalectomy for carcinoma are stage at presentation and complete resection.[19]

Autorino et al, in a systematic literature review and meta-analysis comprising nine retrospective case-control studies, compared open adrenalectomy (n = 557) and laparoscopic adrenalectomy (n = 240) with respect to surgical and oncologic outcomes in patients with adrenocortical carcinoma.[20]  The laparoscopic procedure was associated with a shorter duration of hospitalization and a higher incidence of peritoneal carcinomatosis, but no significant differences were found in overall recurrence rate, time to recurrence, or cancer-specific mortality.

Outcomes for benign lesions, including hormone-secreting lesions, are excellent. Resolution of symptoms is achieved in nearly all patients, except those who have contralateral disease or sites of metastasis (in the case of pheochromocytoma).

 

Periprocedural Care

Patient Education and Consent

Information should be provided to the patient regarding the planned approach to the operation, the approximate length and location of incisions, and the expected postoperative care. In general, operative complication rates are low. Nevertheless, it is important to explain the risks to patients, especially those with suspected adrenal carcinomas, which are often locally invasive.

Knowledge of the relevant anatomic structures in proximity to the left and right adrenal glands will help the clinician remain alert to possible injuries to adjacent structures (eg, aorta, vena cava, small and large bowel, liver, spleen, and ipsilateral kidney). Before undergoing resection for adrenal carcinoma, patients should be counseled about the potential need to perform an ipsilateral nephrectomy. If caval thrombi are present, the patient should be aware of the extensiveness of the surgery required, as well as the possible need for cardiopulmonary bypass when atrial thrombi are present.

Preprocedural Planning

Preoperative assessment should be tailored to the type of adrenal pathology to be addressed. In general, assessment of blood counts and routine chemistry should be obtained preoperatively. Given the proximity to major vascular structures (vena cava and aorta) and multiple arterial and venous supplies, an active type and screen is recommended. Patients should be optimized from a medical standpoint to safely undergo general anesthesia as well.

If the tumor is hormonally active, it is often important to involve endocrinologists for recommendations and consultation in postoperative care. In addition, with adrenal carcinoma, consultations with vascular surgeons and cardiothoracic surgeons are recommended with evidence of vena cava thrombus on the basis of the level of tumor thrombus.

Consultation with anesthesia is important during planned resection of pheochromocytoma because of the preoperative volume contraction and intraoperative blood pressure shifts associated with this procedure, which arise from an adrenergic surge during manipulation of the mass.

In the case of adrenal masses, preoperative evaluation is critical for matching the surgical procedure and anesthesia to the type of mass present. Preoperative computed tomography (CT) or magnetic resonance imaging (MRI) provides invaluable information regarding the size and location of the mass, the involvement of surrounding structures, and the possibility of metastatic disease (in the case of adrenal carcinoma). Additionally, CT and MRI findings can help differentiate a concerning mass from a simple adenoma. A finding of less than 10 Hounsfeld units (HU) on CT is consistent with adenomatous disease, and a finding of HU consistent with fat is indicative of myelolipoma.[6, 9]

MRI is also able to differentiate between adenoma and other pathologies: Adenomas will show signal intensity equivalent to that of the liver on T2-weighted images.[5, 9]  Cost and convenience may preclude the routine use of MRI in diagnosis of adrenal masses, however. Preoperative imaging is also imperative for planning the proper approach to excision, especially in the case of adrenocortical carcinoma, in that invasion of adjacent structures (eg, the inferior vena cava) is a contraindication for laparoscopy.[19, 21]

So-called incidentalomas that are found on imaging for other reasons that are not diagnostic of adenoma should undergo a hormonal workup, especially when there is a history of hypertension requiring multiple medications, periodic episodes of hypertension and flushing, and glucose intolerance. Virilization in females should also lead one to consider a dehydroepiandrosterone (DHEA)-secreting adenoma. It is important to note that incidentalomas do carry the risk of subclinical Cushing syndrome (5-14%), pheochromocytoma (1.5-11%), and aldosteronoma (1.5-3.3%).[6]

To evaluate for hypercortisolism, measurement should include urinary free cortisol, low-dose dexamethasone suppression test, two or three daytime measurements of cortisol level, and measurement of adrenocorticotropic hormone (ACTH).[6, 9, 22, 23, 24, 25]  Serum potassium levels and aldosterone–plasma renin activity ratios are sufficient to diagnose hyperaldosteronism; DHEA sulfate and testosterone levels will diagnose states of androgen excess; pheochromocytoma can be evaluated with either urinary catecholamines/metanephrines or plasma metanephrines.[6, 9, 22, 23, 24, 25]

Some authors have suggested a minimal protocol that consists of performing a pheochromocytoma workup, assessing potassium levels in hypertensive patients, and measuring glucocorticoids and androgens only in patients whose clinical presentations are consistent with an excess of these hormones.[26]  If neuroblastoma or the less common metastatic pheochromocytoma is being considered, iodine meta-iodobenzylguanidine scanning should be performed to help diagnose and appropriately stage this neoplastic process.

Equipment

Standard laparotomy trays are used. For resection of ribs in the posterior and flank approaches, Doyen retractors are needed to elevate the periosteum from the rib, and a rib cutter is used for resection. A standard Bookwalter retractor can be employed to provide self-retaining retraction for the anterior and flank approaches. A Finochietto retractor is used for both the bilateral posterior approach and the thoracoabdominal approach. Depending on the surgeon's preference, an ultrasonic scalpel may be used in lieu of ligature for ligation of small and accessory adrenal vessels.

Monitoring & Follow-up

As expected, routine postoperative follow-up for wound complications, healing, and return to normal activity is warranted. Further follow-up is dictated by the final pathologic examination of the removed specimen. For hypersecreting tumors, with the exception of pheochromocytoma, further follow-up after routine postoperative follow-up is unnecessary.

For pheochromocytoma, the National Comprehensive Cancer Network (NCCN) guidelines recommend that history and physical examination, blood pressure checks, and biomarkers be assessed 3 and 12 months after surgery, every 6-12 months from year 1 through year 3, and annually thereafter for surgically resectable disease.[27] Imaging studies may be obtained when clinically indicated. For cytoreductive surgeries, the recommendations are for the above tests every 3-4 months with imaging when indicated in consultation with radiation oncology and medical oncology for metastases.

Follow-up for adrenocortical carcinoma is based on tumor grade on pathologic section. For low-grade tumors, imaging every 3-6 months and biomarkers (if it was a hormonally active tumor) are warranted.[28]  For high-grade tumors, the clinician also should consider adjuvant radiation therapy or mitotane chemotherapy. In the case of metastatic disease, adrenalectomy can still be considered if it is low-grade and if more than 90% of tumor can be removed surgically; follow-up should be oriented to the residual disease.

 

Technique

Approach Considerations

The approach chosen should maximize exposure to the important structures during surgery. Posterior/flank approaches offer the least efficient access to the vasculature, whereas abdominal approaches portend greater morbidity. It is critical to be mindful of the named vascular structures associated with the adrenal glands, as well as the potential for there to be numerous unnamed collateral vessels associated with large adrenocortical carcinomas.

The main arterial supply to the right adrenal gland is the inferior adrenal artery, a branch of the right renal artery, and venous drainage is directly into the inferior vena cava (IVC). On the left, the main arterial supply comes from the middle adrenal artery, a direct branch from the aorta, and the venous drainage is mainly to the left renal vein via the adrenal vein. Care should be taken with medial dissection of the adrenal gland because there are many anastomotic networks of veins and arteries in addition to the major vascular structures.

Open Excision of Adrenal Gland

Posterior approach

Also referred to as the lumbodorsal approach, this approach has the advantage of allowing the surgeon to remain in an extraperitoneal dissection plane and offers access to both adrenal glands (though this requires two incisions).

Although this approach has several modifications, the standard approach has the patient in the prone position with arms extended over the head. The incision is made over the 11th or 12th rib, with or without a “hockey stick” extension cephalad.[5, 28]

The diaphragm is then dissected cephalad; incision through the diaphragm may be made if necessary. The peritoneum is swept inferiorly, and adjacent retroperitoneal organs are identified and mobilized if necessary.

The vessels of the adrenal can then be ligated and the specimen removed after mobilization.

Although the morbidity of this procedure is reported to be low, previously mentioned rates of nerve or musculosketetal pain may be underreported. Access to vasculature is also limited.

Flank approach

The flank approach will be familiar to the urologist because it can also be used for extraperitoneal access to the kidney. The patient for this approach is positioned in the lateral decubitus position with the pathologic side up. Adequate padding of the patient in this position is imperative to avoid hyperextension of nerves and to protect against the risk of rhabdomyolysis (especially in the obese patient).

The lower leg is flexed and padded at the hip; pillows are used in between the legs, and the upper leg is extended and padded with the lower leg flexed. The lower arm is placed in roughly 90º of extension with an axillary roll, and the upper arm is placed in a flexed, extended posture in the appropriate arm board.

The incision is made over the 11th rib and carried down through the muscle and fascial layers over the 11th rib. The rib is mobilized posteriorly, with care taken to avoid injuring the neurovascular bundle. The rib is then resected, and the retroperitoneal space is entered through the lumbodorsal fascia.

The peritoneum is reflected anteriomedially, and often the vena cava or aorta may be identified when one is operating in the correct anatomic plane, depending on the side. The kidney may be mobilized as well for inferior traction to help expose the adrenal.

Dissection usually begins along the medial side of the gland with ligation of vascular structures. With sharp dissection, the adrenal can be mobilized off the psoas muscle and separated from the ipsilateral kidney.

This approach offers excellent exposure in obese patients, in that their pannus will move anteriomedially and make dissection to the adrenal gland easier than it would be with an anterior approach. As with the posterior approach, vascular access is not as expedient as with anterior approaches. In addition, there is a risk of injury to the pleural reflection at the level of the 11th rib in the midaxillary line and inadvertent entry into the pleural cavity or lung injury. Accordingly, the authors advocate routine postoperative chest radiography to evaluate for pneumothorax and rule out unidentified injuries. This approach also limits the surgeon to evaluation of the ipsilateral gland only.

Anterior subcostal and midline approaches

These two approaches are very familiar to both urologists and general surgeons; exposure to many other organs can be obtained through these approaches.

The subcostal approach is initiated with the patient supine and the incision is made two fingerbreadths below the costal margin. This may be extended across the midline if necessary or extended to a full chevron if access to both adrenals is warranted.

The rectus muscle and fascia are divided medially, and the external oblique, internal oblique, and transversus abdominis are divided with their fascia laterally. The falciform ligament is identified in the right hemiabdomen and ligated after sharp incision of the peritoneum. The colon is then identified and reflected medially by sharp dissection.

The spleen may be mobilized off the colon and kidney on the left by incising the ligamentous attachments, and the liver can be retracted superolaterally after ligamentous attachments are divided on the right. Care must be taken on the right to identify and protect the duodenum and on the left to identify and protect the tail of the pancreas. Both of these structures can be reflected medially with appropriate mobilization when necessary.

The adrenal gland can then be mobilized from medial to lateral, with care taken to ligate vascular branches when encountered and to mobilize the kidney for inferior traction when necessary. The wound is then closed in the standard fashion.

Access with a midline approach is very similar, except that the incision is made from the xiphoid inferiorly, circumscribing the umbilicus. Entry into the peritoneum is obtained after identification of the midline raphe of the rectus sheath and sharp dissection. This approach will obligatorily limit the lateral extent of exposure, in that the adrenal gland on the right is located almost behind the vena cava and on the left in a very deep position when approached in this manner.

This approach offers the advantages of being well known to all surgeons and allowing for bilateral exploration. However, it does lend itself to longer convalescence and a higher rate of ileus, and it may be difficult with obese patients.

The Makuuchi incision, a J- or L-shaped incision designed to optimize exposure and minimize denervation of the abdominal wall, has been used successfully for open adrenalectomy.[29]  It begins cephalad to the xiphoid, continues in the midline to a point 1 cm above the umbilicus, and then extends laterally.

Thoracoabdominal approach

For this approach, the patient is placed in the supine position with the upper torso rotated at a 45º angle with a body roll. The incision is then made through the eighth or ninth intercostal space through the muscle layers and carried medially through the costal cartilage.

The incision is carried through the anterior and posterior rectus sheaths, and the pleura is entered and the lung packed out of the field. During division of the diaphragm, care is taken not to proceed too centrally; the phrenic nerve can be damaged with careless division.

Control of the diaphragm during division with traction sutures is recommended. Entry into the peritoneal cavity and exposure to the adrenal gland is then carried out as described for the anterior approaches.

Closure of the diaphragm in this approach should be done with interrupted figure-eight nonabsorbable suture. The ribs muse be reapproximated. Before complete anterior closure, a chest tube is placed to suction and water seal.

This approach offers excellent exposure to the retroperitoneum and the great vessels while also offering excellent exposure if IVC thrombus is present. However, it has the highest morbidity of all the approaches, carrying the risks of prolonged ileus, pulmonary complications, and need for chest tube placement. Consequently, most authors reserve this approach for large tumors and adrenocortical carcinoma.[5, 28]

Complications

Inadvertent injury to the surrounding structures can occur during adrenalectomy. Vascular injuries can be associated with hemorrhage or ligation of vessels not associated with the adrenal gland. As a consequence of the adrenal gland’s close approximation to the IVC, renal vessels, hepatic vessels, splenic vessels, and lumbar vessels, injury to these structures is possible. Ligation of an upper-pole renal artery branch, the IVC, or mesenteric vessels is also possible.

Damage to adjacent organs is also a concern, depending on the approach chosen. The anterior/thoracoabdominal approaches have more reported bowel injuries, but the flank and posterior approaches are associated with inadvertent pleural injuries. Expert knowledge of the anatomy of the peritoneum and retroperitoneum is of utmost importance to prevent injury and to facilitate intraoperative recognition of such injury to decrease morbidity. Additionally, patients are at risk for wound complications such as breakdown, soft-tissue infection, and dehiscence.

With hormonally active tumors, several other complications may arise that require careful monitoring and management for successful avoidance. With aldosterone-secreting tumors, hyperkalemia may be seen postoperatively as the contralateral adrenal gland’s aldosterone secretion has been inhibited by oversecretion from the removed gland preoperatively. Hypokalemia may also be seen immediately postoperatively. Hypotension can be seen after resection of pheochromocytoma as a consequence of the preoperative alpha-adrenergic blockade.

More significantly, adrenal insufficiency (from downregulation of the hypothalamic-pituitary axis secretion of ACTH from excess cortisol) is a devastating complication of resection for Cushing syndrome if not recognized, aggressively treated, and prophylactically guarded against with steroid replacement. Hypoglycemia and hyperglycemia also may be seen postoperatively.