Adrenalectomy techniques

INTRODUCTION — Surgical adrenalectomy is performed for benign (hormonally active or nonfunctional) and malignant tumors. The optimal approach for adrenalectomy continues to evolve as surgeons develop expertise with minimally invasive surgery (both abdominal and retroperitoneal) in different clinical settings. Regardless of surgical approaches, adrenalectomy is a challenging procedure that, in general, should only be performed by surgeons with specialized training. Adrenalectomies performed by high-volume surgeons were associated with fewer complications and lower cost [1].

Various adrenalectomy techniques and their applications are discussed in this topic. The indications, preoperative evaluations, and outcomes are discussed separately in topic reviews of the management of specific adrenal disorders. (See "Evaluation and management of the adrenal incidentaloma" and "Clinical presentation and evaluation of adrenocortical tumors" and "Treatment of adrenocortical carcinoma" and "Persistent or recurrent Cushing disease: Surgical adrenalectomy" and "Treatment of pheochromocytoma in adults".)

ANATOMY — The anatomy of the adrenal glands is reviewed separately (figure 1 and figure 2). (See "Surgical anatomy of the adrenal glands".)

SELECTION OF OPERATIVE APPROACH — Adrenalectomy can be performed transabdominally, retroperitoneally, or transthoracically. Transabdominal adrenalectomy is more commonly performed and can be accomplished with either open or minimally invasive surgery (MIS) techniques. Open transabdominal adrenalectomy can be performed via an anterior or thoracoabdominal approach. Open retroperitoneal adrenalectomy is accomplished through a posterior approach. MIS approaches include laparoscopic transabdominal and posterior retroperitoneoscopic adrenalectomy (RPA). Thoracoabdominal adrenalectomy is an uncommon procedure and is used in the rare settings of very large tumors, usually with diaphragmatic involvement or tumor extension into the chest [2,3].

Principles of resection — The basic surgical principles to minimize intraoperative complications of an adrenalectomy are the same regardless of surgical approach and include:

●Wide exposure and visualization of the operative field.

●Meticulous isolation and control of major vascular structures.

●Precise adrenal gland and tumor resection using en bloc technique to avoid capsular rupture.

Approach by indication — The selection of operative approach is first dictated by surgeon expertise. When the surgeon is experienced with more than one approach, factors that can influence the choice of surgical approach include large or malignant tumors, bilateral tumors, extensive prior abdominal surgeries, and patient body habitus.

Adrenocortical carcinoma — The preferred surgical treatment of adrenocortical carcinoma (ACC) varies by geographic regions:

●In the United States, open adrenalectomy with removal of adjacent lymph nodes is recommended for known or suspected ACC, regardless of size. This recommendation is endorsed by the National Comprehensive Cancer Network (NCCN) [4], American Association of Clinical Endocrinologists (AACE), and American Association of Endocrine Surgeons (AAES) [5,6]. Open surgery facilitates control or resection of adjacent structures when necessary. (See 'Vascular involvement' below and 'Tumor capsule rupture' below.)

●In Europe, laparoscopic adrenalectomy is performed for stage I or II ACC with a diameter <10 cm. This recommendation is endorsed by the European Society of Endocrine Surgeons [7,8].

Data on the safety and efficacy of MIS for suspected ACC are inconsistent. Some studies suggested more frequent and/or earlier recurrences and a shorter disease-free survival with MIS, or an increase in port-site recurrences [9-11], while other studies have observed comparable outcomes between MIS and open adrenalectomy, particularly for tumors less than 10 cm in size [12-17]. A systematic review found no significant differences in recurrence rates or complications between laparoscopic and open adrenalectomy among 517 patients undergoing surgery for adrenal malignancy [18]. (See "Treatment of adrenocortical carcinoma", section on 'Initial surgery'.)

Pheochromocytoma — Adrenal pheochromocytomas can generally be removed laparoscopically or robotically when safe and feasible [4], although the surgeon must prepare to convert to open surgery in case of intraoperative bleeding (pheochromocytomas are hypervascular lesions) or capsular violation (risk of hypertensive crisis) [19]. Open adrenalectomy is recommended for large (>6 cm) or invasive pheochromocytomas by the 2014 Endocrine Society guidelines [20] and for paragangliomas.

Adrenal incidentaloma — With increasing use of cross-sectional imaging modalities, more and more adrenal lesions are identified serendipitously (ie, adrenal incidentalomas). All patients with adrenal incidentalomas should be evaluated for the possibility of malignancy and hormonal hyperfunction (see "Evaluation and management of the adrenal incidentaloma", section on 'Evaluation for malignancy'). Lesions that are suspicious for malignancies due to aggressive features on imaging studies (eg, inhomogeneous, irregular margins, and local invasion) should be treated the same way as known malignancies with regard to surgical approaches [4]. (See 'Adrenocortical carcinoma' above.)

Otherwise, MIS is the gold standard for removing benign adrenal masses, both functional and nonfunctional, including pheochromocytomas. MIS adrenalectomy is favored because of reduced blood loss, fewer intraoperative complications, earlier patient mobility, decreased length of stay, and faster return to regular activity compared with open surgery [21-32] (see 'Mortality and morbidity' below). Although large tumor size used to be a relative contraindication to MIS adrenalectomy, equipment and techniques have advanced so that no exact dimensional limit still exists [19]. However, tumors >10 cm should be approached cautiously with MIS techniques because they are more likely to be malignant, and large tumor size can lead to more technical difficulties and complications.

MIS adrenalectomy can be performed with either the laparoscopic transabdominal or the posterior RPA approaches. The two techniques are complementary, each with specific advantages and disadvantages (table 1). The choice is again first dictated by surgeon expertise and preference. For surgeons who are experienced with both approaches, the choice is made based on tumor characteristics and the patient's body habitus [33]. A selection algorithm for the two procedures based on patients' anthropometric parameters has been proposed [34].

●Laparoscopic transabdominal adrenalectomy is more widely adopted and is preferred for large tumors (>8 cm), patients with obesity, and when there is potential need for other abdominal procedures.

●RPA is preferred for patients with a history of extensive upper abdominal surgery and those who require bilateral adrenalectomies [35]. RPA offers the most direct access to the adrenal glands, and mobilization of adjacent organs (eg, liver, pancreas) is not necessary, as it is with the transabdominal approach. The primary limitation to the retroperitoneal approach is limited intraoperative workspace, which is problematic for large tumors [36]. RPA can be safely performed for tumors ≤8 cm. In our practice, we perform RPA for tumors ≤6 cm. In addition, RPA has a steeper learning curve; surgeons must be familiar with the anatomy of the retroperitoneum from this vantage point as well as possess expertise in MIS techniques [37].

A 2018 Cochrane systematic review and meta-analysis of five randomized trials only found very low quality evidence that was insufficient to declare an advantage of either a laparoscopic transperitoneal or RPA approach [38]. Thus, the choice should be informed by patient and disease factors as detailed above.

Bilateral adrenalectomy — For patients with bilateral tumors or end-stage Cushing syndrome, we suggest RPA for bilateral adrenalectomies. The RPA approach is more efficient than the transabdominal laparoscopic approach in this setting because it does not require intraoperative patient repositioning. By contrast, the transabdominal approach requires a staged strategy including resection of one gland, closure of the incisions, repositioning the patient, and reentering the abdomen in the contralateral quadrant for removal of the contralateral gland (table 1). This is cumbersome and risks inadvertent extubation during the change of position. Other surgeons who use a transabdominal laparoscopic approach also achieved good results [39].

An open retroperitoneal (posterior) adrenalectomy is an alternative procedure for patients with end-stage Cushing syndrome requiring expeditious bilateral adrenalectomies or those who are not eligible for a transabdominal open or laparoscopic adrenalectomy (eg, multiple prior procedures). However, the open retroperitoneal procedure has largely been replaced by the retroperitoneoscopic or laparoscopic approaches [36,37,40].

Adrenal metastasis — MIS adrenalectomy is the preferred approach for isolated adrenal metastasis from primary malignancies (eg, lung cancer) when surgical resection is indicated [31]. However, findings during preoperative workup of invasion into adjacent organs or periadrenal fat, lymphadenopathy, tumor size >10 cm, and renal vein or inferior vena cava thrombus may lead to the open approach [19]. Additionally, patients who have synchronous adrenal metastasis and require concomitant resection of other abdominal organs (eg, liver resection) should have an open adrenalectomy.

PREOPERATIVE PREPARATION — Preoperative evaluation of an adrenal mass, including biochemical testing of adrenal function, radiographic localization of adrenal tumors, and perioperative management of pheochromocytoma and other adrenal tumors, is discussed separately. (See "Evaluation and management of the adrenal incidentaloma" and "Clinical presentation and evaluation of adrenocortical tumors" and "Treatment of adrenocortical carcinoma" and "Treatment of pheochromocytoma in adults" and "Anesthesia for the adult with pheochromocytoma".)

Prophylactic antibiotics — A first-generation cephalosporin, such as cefazolin, is typically administered intravenously within one hour prior to the incision (table 2). (See "Antimicrobial prophylaxis for prevention of surgical site infection in adults".)

Venous thromboembolism prophylaxis — Patients undergoing intra-abdominal surgery are at a moderate-to-high risk for developing deep venous thrombosis (DVT) and thromboembolism and should receive thromboprophylaxis [41]. DVT prophylaxis is particularly important in patients with Cushing syndrome because they frequently manifest hypercoagulability. (See "Prevention of venous thromboembolic disease in adult nonorthopedic surgical patients".)

Antiemetic medication — An anticholinergic agent, such as a scopolamine transdermal patch, or a selective 5-HT₃ receptor antagonist, such as ondansetron, is administered preoperatively or intraoperatively to reduce postoperative nausea and vomiting commonly associated with an adrenalectomy. (See "Characteristics of antiemetic drugs" and "Approach to the adult with nausea and vomiting", section on 'Postoperative nausea and vomiting' and "Postoperative nausea and vomiting".)

INTRAOPERATIVE CHALLENGES — Based upon the specific tumor type and/or extensiveness of disease, management and technical challenges can be encountered during the resection.

Hemodynamic lability — Patients with a pheochromocytoma may experience hemodynamic lability during adrenalectomy. Prevention and management of this complication is discussed in detail separately. (See "Anesthesia for the adult with pheochromocytoma", section on 'Intraoperative hemodynamic changes'.)

Adrenal insufficiency — In contrast with patients with a pheochromocytoma, patients with an aldosterone- (Conn syndrome) or cortisol-secreting (Cushing syndrome) tumor do not typically experience intraoperative hemodynamic instability. However, to prevent hypotension due to adrenal insufficiency immediately after a unilateral or bilateral adrenalectomy for patients with Cushing syndrome, intravenous hydrocortisone (50 to 100 mg) is administered upon removal of the adrenal gland. This can be quickly transitioned to oral hydrocortisone when the patient resumes oral intake, usually on the day of surgery.

Vascular involvement — Tumors that abut or invade the inferior vena cava (IVC) can result in potentially fatal intraoperative and/or postoperative bleeding. In our experience, hypercortisolism may be associated with friable tissues, including the IVC, with a higher risk of injury. For these reasons, we strongly prefer an open transabdominal approach through an extended right subcostal incision to facilitate immediate access and control of the IVC in the event of an injury or in the clinical setting of vascular involvement. This approach also allows for an en bloc resection of the tumor if it involves the IVC and/or liver. (See 'Resection of inferior vena cava' below and 'Adrenocortical carcinoma' above.)

Tumor capsule rupture — Cancers, such as adrenocortical carcinomas, are at risk of rupture with manipulation of the tumor capsule. The tumor capsule must remain intact during the resection to prevent spillage of tumor cells. Therefore, wide exposure and meticulous dissection of surrounding structures away from the tumor represents the best strategy for resection. Complete resection frequently requires en bloc excision of surrounding structures, including the perinephric fat envelope, retroperitoneal lymph nodes, IVC, spleen, or pancreas. Such resection is best accomplished through an open approach. Recurrent tumors frequently adhere to surrounding structures and organs. (See 'Adrenocortical carcinoma' above.)

LAPAROSCOPIC TRANSABDOMINAL ADRENALECTOMY

Patient positioning — The patient is placed on an inflatable beanbag in the lateral decubitus position, with all bony prominences padded and the area between the iliac crest and 11^th rib overlying the kidney exposed. The patient is rotated backward approximately 15°, and the beanbag is inflated to secure this position (figure 3) [42].

Port and extraction sites — Prior to making any incision for port placement, the skin is infiltrated with a 1% lidocaine and 0.4% bupivacaine (50:50 mixture) solution. The ports should be placed approximately 9 to 12 cm apart, with the most lateral port placed through the flank [42].

For right adrenal gland resections, four trocars (three 5 mm and one 12 mm) are placed in the right subcostal area and midline (figure 4). Additional 12 mm ports may be needed for retraction; however, this is rarely necessary in our experience. For left adrenal gland resections, three ports are usually sufficient. CO₂ is insufflated to a pressure of 13 to 15 mmHg using a Veress needle or open (Hasson) technique (see "Abdominal access techniques used in laparoscopic surgery"). The peritoneal cavity is initially inspected with a 0° laparoscope and then with a 30° laparoscope.

Mobilization and resection — Mobilization, dissection, and resection techniques are dependent upon the anatomic location of the gland to be resected [42]:

Right adrenalectomy — The general principles for resecting the right adrenal gland are as follows (figure 1):

●Incise the peritoneal reflection of the right hepatic triangular ligament and retract the liver and colon medially. The second portion of the duodenum can also be mobilized if needed to facilitate exposure of the right adrenal gland. In our experience, it is rarely necessary to mobilize the hepatic flexure, unless dense adhesions are present or if a large right adrenal tumor extends inferiorly behind the hepatic flexure.

●Incise the anterior renal fascia (Gerota's fascia), a thin fascial layer encompassing the kidney and adrenal gland, vertically over the upper portion of the right kidney, and dissect superiorly to the diaphragm, approximately 4 to 6 cm above the superior pole of the kidney (figure 5).

●Dissect the medial perirenal adipose tissue medially until the lateral border of the inferior vena cava (IVC) is identified.

●Dissect cephalad along the lateral wall of the IVC superiorly to the level of the right diaphragmatic crus. The right adrenal vein is identified along the lateral border of the IVC (figure 6). The vein is meticulously dissected and ligated with Hem-o-lok polymer clips or metal clips, linear vascular stapler, or suture ligatures. In general, we ligate the vein early during the dissection to facilitate lateral retraction and exposure of the adrenal gland. In particular, for patients with a pheochromocytoma, early venous ligation may reduce intraoperative hemodynamic instability (ie, acute hypertensive episode) from catecholamine release. However, when the vein cannot be readily identified or the tumor is adherent to the IVC and requires a partial resection of the IVC, the vein is typically ligated after lateral and inferior mobilization of the gland. Deferring dissection of the superior and lateral aspects of the adrenal gland until the latter part of the procedure helps keep the gland suspended, which facilitates dissection of the medial and inferior aspects of the gland.

●Identify and ligate any accessory adrenal veins that drain into the IVC or liver.

●Identify and ligate or cauterize the multiple small adrenal arteries that arise from the aorta, phrenic, and/or renal arteries as they are encountered to minimize the risk of hemorrhagic rupture of the tumor or bleeding from the adrenal gland (figure 7).

●Dissect the lateral periadrenal adipose tissue containing the adrenal gland from the diaphragm and the superior pole of the kidney en bloc, using electrocautery or another energy device. When dissecting in the groove between the adrenal gland and kidney, use caution in the inferomedial area to avoid injury to the superior pole renal vasculature. Avoid disrupting the capsule of the tumor by grasping the adipose and areolar tissues, rather than directly grasping the adrenal gland and tumor.

●Rotate the adrenal gland laterally and divide the remaining areolar tissue circumferentially between the superomedial border of the gland and the IVC using electrocautery/energy device.

●Place the adrenal gland in an endoscopic retrieval bag and remove it through the larger port, without rupture of the tumor. The port site may be enlarged, as needed, to accommodate the specimen.

Left adrenalectomy — Typically, three 5 mm ports in the left subcostal region are adequate for a laparoscopic transabdominal left adrenalectomy. However, a fourth port may be required for retraction of an enlarged spleen or pancreas. The general principles for resecting the left adrenal gland include (figure 8 and figure 1):

●Mobilize the splenic flexure of the colon by dividing its attachments to the kidney and Gerota's fascia (figure 9). If an additional port is needed, it can be placed under direct vision.

●Mobilize the spleen by dividing the lienophrenic ligament to the level of the gastric fundus. The spleen, pancreas, anterior surface of the Gerota's fascia, and medial edge of the adrenal gland can be fully visualized with this maneuver (figure 10).

●Dissect en bloc in the avascular plane between the posterior surface of the pancreas, with the splenic artery and vein intact, and the anterior surface of Gerota's fascia. Do not injure or incise the tail of the pancreas or the capsule overlying the adrenal gland or tumor. For smaller adrenal tumors, an alternative approach is to incise the fascia along the inferior border of the pancreas and mobilize the body and tail of the pancreas superiorly (figure 11). The left renal vein and the adrenal gland are now exposed (figure 7).

●Identify the left adrenal vein as it courses from the inferior pole of the adrenal gland to the midportion of the renal vein. The left adrenal vein usually drains into the left renal vein; however, variation in vascular anatomy is common. The left phrenic vein is frequently visible along the medial border of the adrenal gland, on its path to join the adrenal vein, after which they both drain into the renal vein. The phrenic vein can be used as a guide to the adrenal vein if the latter is not immediately apparent during dissection (figure 7). Once identified, the left adrenal vein can be divided with methods similar to those used to divide the right adrenal vein.

●Divide and ligate the small-caliber adrenal branches of the left suprarenal and phrenic arteries as they are encountered with electrocautery or another energy device.

●Dissect the medial edge of the adrenal gland from the diaphragm en bloc, and divide and ligate small vessels with electrocautery as described for a right adrenalectomy.

●Place the adrenal gland in an endoscopic retrieval bag and remove through the larger port. The port site may be enlarged, as needed, to accommodate the specimen to avoid rupture or morcellation of the tumor.

Conversion to an open procedure — Conversion from a laparoscopic to an open or hand-assisted laparoscopic procedure is uncommon for experienced surgeons. In a retrospective review of 261 consecutive patients and one surgeon, only 8 patients (3 percent) required conversion to another approach because of tumor adherence to surrounding structures, identification of malignant features, and large size of the mass [43]. A retrospective review of 456 patients undergoing laparoscopic adrenalectomy at two centers found that only 25 patients (5.5 percent) required conversion, with the most common indications including tumor size ≥5 cm, overweight or obese body mass index (BMI; BMI ≥24 kg/m²), and a diagnosis of pheochromocytoma [44].

When conversion is required, a subcostal incision can be created expeditiously by connecting the two or three most medial trocar incisions.

RETROPERITONEOSCOPIC ADRENALECTOMY — For patients who require bilateral adrenalectomies for benign tumors or isolated metastases, and who are not candidates for a transabdominal laparoscopic procedure, retroperitoneoscopic adrenalectomy (RPA) can be performed [36,37,40]. (See 'Adrenal incidentaloma' above and 'Bilateral adrenalectomy' above.)

In a systematic review and meta-analysis of 22 studies, including two randomized trials and 1966 total patients, there were no statistically significant differences between RPA and conventional laparoscopic adrenalectomy for conversion to an open approach, blood loss, duration of operation, time to ambulation, and postoperative oral intake [45]. In a retrospective study of 833 patients, 35 percent underwent RPA and the rest laparoscopic transperitoneal adrenalectomy [46]. RPA was associated with fewer conversions to open surgery, fewer complications, and shorter hospital stays, but a greater rate of capsular disruption (12.6 versus 7.6 percent), which is a bigger problem for malignant lesions.

However, RPA is technically demanding and requires specific training and expertise. In a multicenter international study, 24 to 42 procedures were required to fulfill the learning curve [47]. The general principles of an RPA include [36,37,40]:

Patient positioning — Patient positioning is particularly important to maximize exposure of the adrenal gland. For bilateral adrenalectomies, the patient is placed in the prone position, with the hips and knees flexed at approximately 90° (figure 12). For a unilateral adrenalectomy, the patient may be turned slightly to the contralateral side to facilitate port placement and provide protection of the intra-abdominal organs (figure 13).

Port placement sites — Three incisions, two 12 mm and one 5 mm, are typically used for trocar placement. Trocar entry into the retroperitoneum is confirmed by direct vision. The first incision is placed approximately 1 cm inferior to the tip of the 12^th rib (figure 13 and figure 12), and the retroperitoneum is bluntly entered deep to the ribs and diaphragm. With an index finger directly in the retroperitoneum, an incision is made laterally at the posterior axillary line and a blunt trocar inserted. A trocar is inserted between the first trocar site and the spine, along the paraspinal muscles, approximately 4 cm from the inferior border of the 12^th rib. A 12 mm balloon trocar is then placed in the first incision and carbon dioxide insufflation performed to a limit of 20 mmHg. This relatively higher insufflation pressure is important to create working space in the retroperitoneum. It is also helpful in temporarily reducing bleeding from small venous structures during dissection; however, we always reduce the pressure and control such bleeding prior to termination of the procedure.

Exposure — A critical step of the RPA procedure is exposure of the superior pole of the kidney by identifying and opening the overlying Gerota's fascia using electrocautery and endoscopic graspers. Dissection of the superior pole from lateral to medial results in separating the adrenal gland containing the tumor and the surrounding perinephric fat from the kidney. After complete mobilization of the superior pole, the retroperitoneal fat containing the adrenal gland is retracted cephalad.

Resection — The next critical step is to identify and secure the blood supply to the adrenal gland. The adrenal arteries are identified on the inferior and medial aspects of the adrenal gland and may be divided using electrocautery. Large arteries may require control with surgical clips. The main adrenal vein is usually controlled with surgical clips. The resection is performed en bloc, with meticulous attention to avoid rupture of the gland and tumor. The adrenal gland is then separated from the peritoneum anteriorly, the insufflation decreased, and the gland placed intact into the extraction bag.

Conversion to an open procedure — Occasionally, RPA requires conversion to open surgery (either retroperitoneal adrenalectomy or a transabdominal approach) after a patient position change. This decision depends strongly on available surgical expertise, disease process, and patient factors such as body mass index. Our preference is to convert RPA to an open retroperitoneal adrenalectomy via a retroperitoneal open incision with a 12^th rib resection. (See 'Retroperitoneal open adrenalectomy' below.)

OPEN TRANSABDOMINAL ADRENALECTOMY — An open transabdominal adrenalectomy is typically performed in the following clinical settings to avoid rupture and spillage of malignant or large tumors [9,13,29,48-56] (see 'Approach by indication' above):

●Primary adrenal malignancy of any size (eg, adrenal cortical carcinoma, malignant pheochromocytoma).

●Adrenal mass invading surrounding structures (eg, liver, kidney, inferior vena cava).

●Adrenal mass suspicious but not confirmed as a primary adrenal malignancy (eg, >6 cm, irregular margins, hemorrhage or central necrosis, hypervascular).

●Bilateral benign adrenal masses not accessible to the laparoscopic approach.

●Extensive prior upper abdominal or retroperitoneal procedures that preclude a minimally invasive surgical (MIS) approach.

●Concomitant procedures (eg, hepatic resection) not amenable to laparoscopic approach.

Patient positioning — For a unilateral adrenalectomy, the patient is positioned supine with the ipsilateral flank elevated with a soft cushion or gel form, which permits adequate exposure and operative flexibility if there is a need for more exposure or extension of the scope of surgery. For bilateral adrenalectomies, the flank is not elevated.

Incision — The adrenalectomy is performed through either an upper midline or subcostal incision, depending upon surgeon preference. Midline or extended subcostal incisions are preferred for bilateral adrenal resections, retroperitoneal dissection and exploration, and when non-adrenal-related procedures are to be performed in the same setting. Other surgeons prefer a modified Makuuchi incision, designed to optimize exposure and minimize denervation of the abdominal wall [57].

Techniques for resection — The exposure, mobilization, and resection of the adrenal glands using an open approach are similar to that described for the laparoscopic transabdominal approach (see 'Mobilization and resection' above). Additionally, open surgery readily permits resection of adjacent structures when necessary:

Resection of inferior vena cava — The general principles for resecting tumor involvement of the inferior vena cava (IVC) include:

●If the right adrenal tumor invades the IVC, the resection is performed by extensively mobilizing the adjacent liver and dissecting along the lateral border of the IVC, from caudad to cephalad. After proximal and distal vascular control, the involved portion of IVC is resected and the defect repaired with a nonabsorbable monofilament suture. Small vessels are controlled with ligatures or energy devices. Larger vessels require suture ligation.

●If there is extensive IVC involvement requiring partial IVC resection, or an intracaval tumor thrombus, vascular bypass may be necessary [58,59]. Arterial vessels pass behind the inferior vena cava from the aorta and can retract posterior to the IVC if not effectively controlled. Bleeding in this situation can be extremely difficult to control.

●Once the tumor is resected from the IVC, the dissection continues in a medial-to-lateral fashion, typically without further risk of vascular challenges.

Resection of adjacent organs — If the adrenal tumor invades solid organs, such as the liver, kidney, or pancreas, an en bloc resection should be performed. The operative approaches for resecting these adjacent organs are reviewed in separate topics. (See "Overview of hepatic resection" and "Surgical resection of lesions of the body and tail of the pancreas".)

Drains — Routine drain placement after adrenal surgery is rarely necessary; however, drains may be helpful if there is concern regarding a retroperitoneal lymphatic, pancreatic, or urinary leak. (See "Surgical repair of an iatrogenic ureteral injury".)

If the adrenal gland is very large, the dissection is extensive, or there is a persistently oozing bed, a closed-suction drain can be placed to prevent a fluid collection. The drain can be removed safely when the drain output is serous and decreasing in volume.

RETROPERITONEAL OPEN ADRENALECTOMY — The retroperitoneal open adrenalectomy is performed through a paraspinous or horizontal incision, division of the latissimus dorsi muscle, reflection of the parietal pleura upward, and resection of the 12^th or occasionally 11^th rib, which contributes to considerable incisional pain, subcostal nerve neuropathy, and lumbar hernias [36].

EVOLVING TECHNOLOGIES — As surgeon experience grows, evolving minimally invasive technologies such as single-access retroperitoneoscopic adrenalectomy (SARA) are being developed. However, we recommend that such procedures should only be performed in highly specialized centers by experienced care teams.

Robotic-assisted adrenalectomy — Robot-assisted techniques have been applied to both transabdominal and retroperitoneal adrenalectomy [60-62]. Retroperitoneal adrenalectomy particularly lends itself to a robot-assisted technique because the retroperitoneal space is limited and frequently requires dissection using angled instruments. A robot-assisted approach may be very useful in the retroperitoneoscopic approach for patients with a hostile abdomen or those requiring concomitant bilateral adrenalectomy, such as those with severe Cushing syndrome. (See 'Bilateral adrenalectomy' above.)

Numerous studies have compared outcomes between robotic-assisted and laparoscopic adrenalectomy with very few clear advantages for either approach:

●A meta-analysis reviewed 1162 patients within 27 studies and found similar clinical outcomes (intraoperative and postoperative complications, mortality, conversion of laparotomy, and blood loss), although robotic adrenalectomy was associated with a shorter hospital stay and longer operative time [63].

●A meta-analysis evaluated nine studies involving 600 patients who had either laparoscopic or robot-assisted adrenalectomy between 2004 and 2013 [64]. Operative times were similar, with no difference in conversion rates or complication rates, but a significantly higher estimated blood loss and hospital stay were identified in the laparoscopic group compared with the robotic group. Given the higher body mass index (BMI) in the laparoscopic group, this study demonstrated equivalence in outcomes. Unfortunately, the differential cost between both groups was not examined as part of this study.

●A direct comparison of laparoscopic transabdominal adrenalectomy (LTA), posterior retroperitoneal adrenalectomy (RPA), and robotic adrenalectomy (RA) in a systemic review [65] revealed that RPA was more effective than LTA, with a shorter operative time and hospital stay. Again, very few studies have compared the cost of RA to that of other approaches; however, extrapolation from other robotic surgical procedures would suggest a higher cost of RA.

●A retrospective comparative study of 1005 patients from the surgical registry EUROCRINE found that the complication rate was lower (1.6 versus 16.5 percent) and the length of stay was shorter after robotic adrenalectomy than after laparoscopic adrenalectomy [66].

Single-access retroperitoneoscopic adrenalectomy — The single-access retroperitoneoscopic adrenalectomy (SARA), a highly specialized procedure requiring specific expertise, has been shown to be safe and effective for patients with benign adrenal masses [22,24,36,37,67-73]. In a matched-pair study of 94 patients undergoing an adrenalectomy, patients undergoing SARA had a similar complication rate compared with patients undergoing the conventional retroperitoneoscopic approach (8.5 versus 6.4 percent) [73]. Patients undergoing SARA had significantly longer mean operative times (56 versus 40 minutes) and shorter duration of hospital stay (2.4 versus 3.1 days). There were no deaths in either group.

Partial adrenalectomy — Partial adrenalectomy may be a reasonable alternative to complete adrenalectomy for small, potentially benign adrenal lesions and may be preferred for bilateral small lesions [74]. Partial adrenalectomy has been reported with the laparoscopic transabdominal approach [75] and the retroperitoneoscopic approach [76]. Although there are no established consensus or guidelines, most experts consider it reasonable to perform a partial adrenalectomy for lesions <3 cm that are located anteriorly or laterally in the adrenal gland (to preserve the adrenal vein) [77]. A minimal clear margin of 2 to 3 mm is required. An advanced vessel sealing device and/or fibrin glue may be used to ensure hemostasis at the transection margin, as the risk of bleeding with partial adrenalectomy is higher than that of a complete adrenalectomy [75].

POSTOPERATIVE MANAGEMENT — Most patients are hospitalized postoperatively. The length of stay is typically determined by the surgical approach [22,27,28,78,79]. The length of stay is typically one to two days after an uncomplicated laparoscopic or retroperitoneoscopic adrenalectomy, while a hospitalization of three to five days is expected for patients undergoing an open adrenalectomy. Our mean hospital stay for laparoscopic transabdominal adrenalectomy (LTA) or retroperitoneoscopic adrenalectomy (RPA) is less than one day. In selected cases, minimally invasive adrenalectomies have been performed as outpatient procedures at experienced centers [80].

Patient-controlled analgesia (PCA) combined with the use of orally administered narcotics is the standard protocol for postoperative pain control. (See "Approach to the management of acute pain in adults".)

Postoperative endocrine management of patients with adrenocortical tumors (see "Treatment of primary aldosteronism" and "Treatment of adrenocortical carcinoma" and "Evaluation and management of the adrenal incidentaloma") and pheochromocytoma (see "Treatment of pheochromocytoma in adults", section on 'Surgical outcomes') is reviewed separately.

MORTALITY AND MORBIDITY — Contemporary adrenalectomy (both open and minimally invasive surgical [MIS] approaches) is associated with a very low risk of mortality (none in most reported series), and morbidity rates range from 6 to 30 percent [23,29,36,40,73,81-83].

There are no randomized trials assessing mortality or morbidity for open versus laparoscopic approaches to an adrenalectomy [23]. Based upon retrospective reviews, MIS adrenalectomy is safe, effective, and less expensive than open adrenalectomy for patients with benign functional and nonfunctional adrenal masses.

The following retrospective reviews illustrate the safety and efficacy of the laparoscopic approach:

●Patients undergoing laparoscopic adrenalectomy had fewer postoperative complications than patients undergoing open adrenalectomy (10 versus 27 percent) [23,83]. Patients undergoing laparoscopic adrenalectomy also had a shorter operative time (189 versus 219 minutes), reduced mean blood loss (125 versus 563 cc) and narcotic requirements (38.2 versus 471.6 mg morphine equivalent), and shorter duration of hospital stay (1.9 versus 7.6 days) compared with patients undergoing open surgery. The intraoperative complication rates were comparable between the two groups.

●A review of 72 consecutive laparoscopic adrenalectomies found no mortality and no statistical difference in postoperative complications based upon operative indications (type of adrenal mass) [82].

●A multicenter review of 370 patients undergoing a laparoscopic adrenalectomy reported that 33 patients (9 percent) had intraoperative complications, including conversion to open procedure (4 percent), blood transfusion (5 percent), vascular injuries (5 percent), and visceral injuries (3 percent) [81].

The risk of intra-abdominal injury is minimal with a retroperitoneoscopic adrenalectomy (RPA) procedure, and morbidity includes wound infections, subcostal nerve injury, and chronic lumbar pain [36]. A retrospective review of 14 patients undergoing an RPA found no statistical difference in mean operating time or duration of hospital stay compared with 23 patients undergoing a transabdominal laparoscopic approach (3.8 versus 3.4 hours, 2.2 versus 1.5 days, respectively) [24]. Masses larger than 6 cm were resected using the transabdominal laparoscopic approach. There were no conversions to an open procedure.

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Adrenal cancer".)

SUMMARY AND RECOMMENDATIONS

●Surgical principles – Adrenalectomy is a challenging procedure that, in general, should only be performed by surgeons with specialized training. The basic surgical principles of all adrenalectomy techniques include adequate exposure, meticulous vascular control, and precise dissection of the gland and tumor, using an en bloc technique to avoid capsular rupture. (See 'Introduction' above and 'Principles of resection' above.)

●Surgical approaches by indication

•For patients with a benign functional or nonfunctional adrenal mass (including pheochromocytoma) or an isolated metastasis undergoing adrenalectomy, we recommend a minimally invasive approach rather than an open approach (Grade 1B). A minimally invasive approach is favored because of reduced blood loss, fewer intraoperative complications, earlier patient mobility, decreased length of stay, and faster return to regular activity compared with open surgery. Minimally invasive adrenalectomy can be performed transabdominally or retroperitoneally, depending upon surgeon preference and expertise (table 1). (See 'Approach by indication' above.)

•For patients with a malignant or suspicious adrenal mass (eg, malignant pheochromocytoma, adrenocortical carcinoma) and those who are not candidates for minimally invasive surgery (eg, multiple previous procedures), we suggest an open adrenalectomy (Grade 2C). Malignant tumors may invade adjacent structures (inferior vena cava, liver, spleen, pancreas, colon) that require resection. (See 'Approach by indication' above and 'Resection of inferior vena cava' above and 'Resection of adjacent organs' above.)

•For patients who require bilateral adrenalectomy (eg, for end-stage Cushing syndrome), we suggest a retroperitoneoscopic adrenalectomy (RPA) rather than a transabdominal laparoscopic approach or an open approach (Grade 2C). RPA is more efficient because it does not require repositioning the patient after resecting the first gland. (See 'Approach by indication' above and 'Retroperitoneoscopic adrenalectomy' above.)

●Evolving technologies – Minimally invasive technologies such as robotic-assisted adrenalectomy and single-access retroperitoneoscopic adrenalectomy are evolving but should only be performed by experienced surgeons at specialized centers. (See 'Evolving technologies' above.)