Posterior Retroperitoneoscopic Versus Laparoscopic Transperitoneal Adrenalectomy: A Systematic Review by an Updated Meta-Analysis

Impact of Obesity on Short-Term Outcomes in Patients Undergoing Retroperitoneal Laparoscopic/Retroperitoneoscopic Adrenalectomy for Benign or Malignant Adrenal Diseases: A Meta-Analysis

Background and Objectives: Retroperitoneal laparoscopic adrenalectomy (RLA) is one of two laparoscopic procedures used to treat benign and malignant adrenal diseases. Obesity in patients undergoing minimally invasive adrenal surgery is a frequently discussed topic. Our meta-analysis aimed to provide updated evidence by comparing intraoperative and perioperative outcomes on non-obese (NOb) and obese (Ob) patients who underwent RLA due to benign or malignant disease. Materials and Methods: We performed a systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed/MEDLINE, Scopus, Web of Science (Science and Social Science Citation Index), and Cochrane Library (Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials (CENTRAL)) databases were used to identify articles of interest. The meta-analysis was performed using RevMan [Computer program] Version 5.4. Results: The four included comparative studies (809 patients: 552 NOb versus 257 Ob) covered an approximately 15-year-study period (2007-2022). All the included studies were observational in nature. By comparing the Ob and NOb groups, shorter operative time and lower overall postoperative complication rates in the NOb population were recorded through the meta-analysis. Considering the subgroup analysis (BMI ≥ 30 kg/m2), just the operative time maintained statistical significance. Conclusions: Obesity did not appear to impact RLA safety and effectiveness. Due to important biases (small overall sample size and few analyzed events), the interpretation of our results must be a careful one. Later randomized and multi-center trials may help the confirmation of our results.

Posterior retroperitoneal adrenalectomy for metastatic disease: a multi-site Australian series

BACKGROUND

Posterior retroperitoneoscopic adrenalectomy (PRA) for isolated adrenal metastasis is minimally invasive, may prolong survival and improve quality of life. The current evidence base is scant.

METHODS

A multi-site retrospective analysis of all cases of PRA for adrenal metastasis between 2011 and 2023, by four high-volume adrenal surgeons was performed. Perioperative morbidity, disease-free and survival outcomes were reported.

RESULTS

Of 51 patients, 34(67%) male, mean age 63 ± 12 years, mean BMI 28; 49 PRAs for adrenal metastatectomy were completed (one abandoned due to tumour unresectability, one conversion to anterior laparoscopic approach) across 11 hospitals (49% public). Primary tumours included: 11 colorectal, 11 renal, 8 lung, 6 hepatocellular, 4 sarcoma, 3 breast, 2 melanoma, 2 ovarian and 1 each of pancreatic, oesophageal, testicular and prostate cancer. There were 12 synchronous (<6 months) and 39 metachronous (>6 months after primary diagnosis) tumours; 21 (42%) left sided, none bilateral. Mean operative time was 95 ± 34 minutes, mean maximal tumour diameter was 34 mm ± 13 mm and median length of hospitalization 1 ± 1 days. There were 8 (16%) complications; 1 ICU admission, 1 re-admission for pneumonia and 6 Clavien-Dindo grade I complications. There were 10 (20%) mortalities and a median overall survival of 29 months (range 7-123, n = 41). Disease recurred in 15 (40%) patients (n = 37), with a median disease-free interval of 18 months (range 1-68). Port site recurrence occurred in 2 patients, both simultaneously with disseminated metastases.

CONCLUSION

In carefully selected patients with adrenal metastases, PRA by high-volume adrenal surgeons has minimal morbidity and short hospitalization. Surgery should be considered prior to local ablation.

Multiple Endocrine Neoplasia Type 1, Type 2A, and Type 2B

Multiple endocrine neoplasia type 1 is a rare genetic neuroendocrine syndrome caused by over 1500 different germline mutations. It can cause 20 different endocrine tumors affecting primarily the parathyroid glands, gastroenteropancreatic tract, and the anterior pituitary gland. Multiple endocrine neoplasia type 2A (MEN2A) and Multiple endocrine neoplasia type 2B (MEN2B) are autosomal dominant genetic syndromes because of a germline variant in the 'rearranged during transfection' (RET) proto-oncogene. There are common RET mutations causing receptor hyperactivation and induction of downstream signals that cause oncogenesis. Common conditions with MEN2A are medullary thyroid cancer (MTC), pheochromocytoma, and primary hyperparathyroidism. Common conditions with MEN2B include MTC, pheochromocytomas, and benign ganglioneuromas.

Idiopathic giant adrenal calcification: a rare case report

Background

We describe a rare case of giant adrenal calcification as the main cause of sudden onset epigastric pain in a 57-year-old female patient.

Case description

Computed tomography (CT) of the whole abdomen in this patient showed calcified foci measuring approximately 7.8 × 5.4 × 7.1 cm in the hepatorenal recess, and no enhancement effect was seen. Secondary causes of adrenal calcification in this patient were ruled out, and a rare diagnosis of a primary giant adrenal calcification was made. Subsequently, the right adrenal gland and calcified mass were completely resected. The calcification did not recur during 6 months of follow up.

Conclusions

Although other cases of adrenal calcification of unknown origin have been reported, cases of giant idiopathic adrenal calcification are rare. In this case, huge calcification of the right adrenal gland caused abdominal pain, which disappeared after the mass was excised. The etiology, pathogenesis, clinical symptoms, and prognosis of idiopathic adrenal calcification are still unclear. Additional case reports are needed to gain a better understanding of the diagnosis and treatment of this condition.

Modified versus three-level technique of retroperitoneal laparoscopic adrenalectomy for all patients with adrenal lesions ≤ 6cm: a retrospective, case-controlled study

Objectives

The modified three-level technique for retroperitoneal laparoscopic adrenalectomy (RLA) has proven beneficial in the treatment of adrenal lesions in patients with BMI≥25 Kg/m2. This paper aims to summarize our institution's seven-year experience using this technique for all patients with Adrenal Lesions ≤ 6cm.

Patients and methods

Between January 2016 and December 2022. The patients underwent laparoscopic adrenal surgery were categorized into Zhang's technique (ZT) (Three-level Technique) group and modified technique (MT) group. The fundamental characteristics and perioperative data were analyzed, with statistical significance set at p<0.05.

Results

In total, 731 patients were stratified into two groups: ZT (n=448) and MT (n=283). Statistically significant distinctions were not detected between the two groups regarding sex, BMI, tumor location, tumor size, tumor type, or American Society of Anesthesiologists (ASA) score (p>0.05). The MT group demonstrated superior outcomes compared to the ZT group in terms of operative time, estimated blood loss, drainage volume, diet recovery time, complication rates, and postoperative hospitalization duration (p<0.05). 17 (4.34%) in the ZT group required unplanned adrenalectomy, while there was none in MT group (P<0.05).

Conclusion

MT retroperitoneal laparoscopic adrenalectomy has demonstrated its benefits in the treatment of adrenal lesions across all patients with adrenal lesions ≤ 6cm, serving as a valuable point of reference for the surgical management of adrenal diseases.

Patient summary

We have made modifications to the classic retroperitoneal laparoscopic adrenalectomy and achieved superior surgical outcomes, resulting in a procedure known as modified retroperitoneal laparoscopic adrenalectomy. This technique is suitable for both obese individuals and the general population with adrenal lesions ≤ 6cm.

[Surgical treatment of pheochromocytoma]

This review article contains a summary of modern aspects of preoperative preparation, surgical treatment, and follow-up of patients with adrenal pheochromocytomas. The main component of preoperative preparation is the use of alpha-blockers. The need to prescribe them to all patients is increasingly disputed, especially for patients without severe hypertension. An increasing number of publications demonstrate positive results of treatment without the use of alpha-blockers, advocating an individual approach and the use of the drug according to certain indications. Minimally invasive endoscopic techniques of adrenalectomy have become widespread in surgical treatment. They are represented by laparoscopic and retroperitonescopic technic, including using their single-port modifications. The earliest possible intersection of the central vein in the past was considered the most important aspect of adrenalectomy for pheochromocytoma, currently, due to the development of surgical techniques and anesthesiological manuals, this has ceased to be a mandatory rule of successful surgery. Despite the significant influence of the intersection of this vessel on intraoperative hemodynamics, surgical tactics with its later intersection have their own justifications and do not lead to a deterioration in treatment results. The standard volume of surgical intervention for pheochromocytomas is total adrenalectomy, however, in the presence of hereditary syndromes, such as multiple endocrine neoplasia type 2 syndrome, neurofibomatosis type 1, von Hippel-Lindau syndrome, it is possible to perform cortical-sparing adrenalectomy.

Retroperitoneoscopic adrenalectomy may be superior to laparoscopic transperitoneal adrenalectomy in terms of costs and profit: a retrospective pair-matched cohort analysis

BACKGROUND

A direct comparison of the cost-benefit analysis of retroperitoneoscopic adrenalectomy (RPA) versus the minimally invasive transperitoneal access (LTA) approach is currently lacking. We hypothesized that RPA is more cost effective than LTA; promising significant savings for the healthcare system in an era of ever more limited resources.

METHODS

We performed a monocentric retrospective observational cohort study based on data from our Endocrine Surgery Registry. Patients who were operated upon between 2019 and 2022 were included. After pair-matching, both cohorts (RPA vs. LTA) were compared for perioperative variables and treatment costs (process cost calculation), revenue and profit.

RESULTS

Two homogenous cohorts of 43 patients each (RPA vs. LTA) were identified following matching. Patient characteristics between the cohorts were comparable. In terms of both treatment-associated costs and profit, the RPA procedure was superior to LTA (costs: US$5789.99 for RPA vs. US$6617.75 for LTA, P = 0.043; profit: US$1235.59 for RPA vs. US$653.33 for LTA, P = 0.027). The duration of inpatient treatment and comorbidities significantly influenced the cost of treatment and the overall profit.

CONCLUSIONS

RPA appears not only to offer benefits over LTA in terms of perioperative morbidity and length of hospital stay, but also has a superior financial cost/benefit profile.

Emerging Potential of Microwave Ablation for Primary Aldosteronism Resulting From Unilateral Aldosterone-producing Adenoma

Primary aldosteronism (PA) is the most prevalent form of secondary hypertension and is most commonly caused by an adrenal adenoma or bilateral adrenal hyperplasia. Minimally invasive adrenalectomy is the treatment of choice for unilateral disease. Here, we report the case of a 57-year-old man with previous bladder cancer who was referred for evaluation of resistant hypertension and hypokalemia. Diagnostic workup indicated PA with computed tomography imaging revealing a left adrenal adenoma and adrenal venous sampling lateralizing to the left adrenal. He was therefore referred for a left adrenalectomy using a retroperitoneoscopic approach. However, surgery was complicated by significant perinephritis related to previous bladder cancer immunotherapy and, in view of an identifiable adrenal adenoma, a partial adrenalectomy was performed. Despite histology confirming removal of an adrenal adenoma, he remained hypertensive and hypokalemic with persistent PA. He underwent a computed tomography-guided percutaneous thermal (microwave) ablation of the residual adrenal nodule with immediate biochemical reversal of PA. Six years postprocedure, he remains biochemically and clinically cured from PA. This article presents the details of the case and reviews the literature on long-term outcomes for patients undergoing thermal ablation and adrenalectomy, suggesting that thermal ablation may be a viable alternative for selected patients.

Posterior retroperitoneal versus transperitoneal laparoscopic adrenalectomy in adults: results from the EUROCRINE® surgical registry

PURPOSE

This study aims to compare posterior retroperitoneal laparoscopic adrenalectomy (PRLA) and laparoscopic transperitoneal adrenalectomy (LTA) in adults using pan-European data as conflicting results have been published regarding length of hospital stay, institutional volume, and morbidity.

METHODS

This retrospective cohort study analyzed data from the surgical registry EUROCRINE®. All patients undergoing PRLA and TLA for adrenal tumours and registered between 2015 and 2020 were included and compared for morbidity, length of hospital stay, and conversion to open surgery.

RESULTS

A total of 2660 patients from 11 different countries and 69 different hospitals were analyzed and 1696 LTA were compared to 964 PRLA. Length of hospital stay was shorter after RPLA, with less patients (N = 434, 45.5%, vs N = 1094, 65.0%, p < 0.001) staying more than 2 days. In total, 96 patients (3.6%) developed a complication Clavien-Dindo grade 2 or higher. No statistical difference was found between both study groups. After propensity score matching, length of hospital stay was shorter after PRLA (> 2 days 45.2% vs 63.0%, p < 0.001). After multivariable logistic regression, factors associated with morbidity were age (OR 1.03), male sex (OR 1.52), and conversion to open surgery (OR 5.73).

CONCLUSION

This study presents the largest retrospective observational analysis comparing LTA and PRLA. Our findings confirm the shorter length of hospital stay after PRLA. Both techniques are safe leading to comparable morbidity and conversion rates.

Adrenal cysts: an emerging condition

Adrenal cysts are rare lesions representing approximately 1-2% of adrenal incidentalomas. The majority of these rare lesions are benign. Rarely, phaeochromocytomas and adrenal malignant masses can present as cystic lesions and can occasionally be difficult to distinguish from benign cysts. Histologically, adrenal cysts are subdivided into pseudocysts, endothelial cysts, epithelial cysts and parasitic cysts. The radiological appearance of an adrenal cyst is generally similar to that of cysts in the kidney. They are thus well demarcated, usually rounded, with a thin wall and homogenous internal structure, low attenuating (<20 Hounsfield Units) on CT, low signalling on T1-weighted MRI sequences and high signalling on T2-weighted MRI sequences, and anechoic or hypoechoic on ultrasonography. Benign adrenal cysts have a slight female predominance and are usually diagnosed between the ages of 40 and 60. Most adrenal cysts are asymptomatic and are detected incidentally, although very large adrenal cysts can lead to mass effect symptoms, with surgery required to alleviate the symptoms. Thus, conservative management is usually recommended for asymptomatic cysts. However, when uncertainty exists regarding the benign nature of the cyst, additional work-up or follow-up is needed. The management of an adrenal cyst should preferably be discussed at an adrenal multidisciplinary team meeting.

Perception versus reality: A case-matched study assessing the intraoperative hemodynamics of minimally invasive retroperitoneal versus transperitoneal approach to pheochromocytomas

BACKGROUND

Pheochromocytomas produce excess catecholamines that can result in intraoperative hemodynamic instability. Centers have reported variations in intraoperative hemodynamics with the retroperitoneoscopic versus the laparoscopic transperitoneal approach to adrenalectomies. When the retroperitoneoscopic approach was initiated for pheochromocytomas at our institution, the perception was of improved intraoperative hemodynamics, hypothesizing that increased retroperitoneoscopic insufflation pressures caused decreased venous return and less fluctuation in circulating catecholamines. The purpose of this study was to examine if a difference in intraoperative hemodynamics exists between a size-matched cohort of laparoscopic transperitoneal and retroperitoneoscopic pheochromocytoma patients.

METHODS

Unilateral adrenalectomies for pheochromocytoma performed via laparoscopic transperitoneal or retroperitoneoscopic approaches from 2015 to 2021 were identified from a surgical database. As larger tumors often underwent a laparoscopic transperitoneal approach, cases were matched 1:1 by tumor size. All patients received phenoxybenzamine. Groups were compared by patient characteristics, preoperative blockade, intraoperative hemodynamics and management, and early postoperative outcomes.

RESULTS

There were 13 laparoscopic transperitoneal adrenalectomy cases matched to 13 retroperitoneoscopic cases according to tumor size. Both groups (laparoscopic transperitoneal and retroperitoneoscopic) were similar for age (53 years), body mass index (28.5 vs 29.7), sex (69% female), and side (8 vs 7 right). There was no difference in preoperative 24-hour urine metanephrines/normetanephrines (9.9/8.0 vs 2.4/5.7 μmol/day). The phenoxybenzamine dose was similar in both groups (112 vs 114 mg/24 hours), as were baseline heart rate, blood pressure, and mean arterial pressure. There was no difference in any intraoperative hemodynamic parameters or vasoactive interventions. Operative time, length of stay, and 30-day emergency visits were similar between groups.

CONCLUSION

This matched cohort study did not find a difference in intraoperative hemodynamics between laparoscopic transperitoneal and retroperitoneoscopic adrenalectomy approaches for pheochromocytoma in appropriately selected and blocked patients.

Is transperitoneal laparoscopic adrenalectomy for pheochromocytoma really more challenging? A propensity score-matched analysis

PURPOSE

Minimally invasive surgery is the gold standard treatment for adrenal masses, but it may be a challenging procedure in the case of pheochromocytoma (PHEO). The aim of the present study is to report the results of transperitoneal laparoscopic adrenalectomy (TLA) in cases of PHEO in comparison to other types of adrenal lesions.

METHODS

From 1994 to 2021, 629 patients underwent adrenalectomy. Twenty-two and thirty-five patients, respectively, were excluded because they underwent bilateral and open adrenalectomy, leaving 572 patients for inclusion. Of these, 114 patients had PHEO (Group A), and 458 had other types of lesions (Group B). To adjust for potential baseline confounders, a propensity score matching (PSM) analysis was conducted.

RESULTS

After PSM, 114 matched pairs of patients were identified from each group. Statistically significant differences were not observed when comparing the median operative time (85 and 90 min in Groups A and B, respectively, p = 0.627), conversion rate [6 (5.3%) in each group, p = 1.000], transfusion rate [4 (3.5%) and 3 (2.6%) in Groups A and B, respectively, p = 1.000], complication rate [7 (6.1%) and 9 (7.9%) in Groups A and B, respectively, p = 0.796), median postoperative hospital stay (3.9 and 3.6 days in Groups A and B, respectively, p = 0.110), and mortality rate [1 (0.9%) in each group, p = 1.000].

CONCLUSIONS

Based on this analysis, the results of TLA for PHEO are equivalent to those of TLA for other types of adrenal lesions, but the fundamental requirements are multidisciplinary patient management and adequate surgeon experience. Further prospective studies are required to draw definitive conclusions.

Robotic-assisted laparoscopic adrenalectomy (RARLA): What advantages and disadvantages compared to retroperitoneal laparoscopic adrenalectomy (RLA)?

OBJECTIVE

To explore the advantages and disadvantages of robot-assisted laparoscopic adrenalectomy compared with retroperitoneal laparoscopic adrenalectomy.

METHODS

A total of 101 patients with adrenal tumors who received retroperitoneal laparoscopic adrenalectomy (RLA) (n=75) or robot-assisted laparoscopic adrenalectomy (RARLA) (n=26) in our hospital from January 2021 to December 2021 were retrospectively collected. Patients' demographics, tumor characteristics, and perioperative indicators were compared. Statistical analysis was performed using t-test for continuous variables and Pearson chi-square test or Fisher's exact test for categorical variables.

RESULTS

We found that blood loss in the RARLA group was significantly less than that in the RLA group (66.9 ± 35.5 ml vs 91.5 ± 66.1 ml, p = 0.020). Gastrointestinal function recovery time in RARLA group was significantly less than that in RLA group (19.9 ± 6.9 hours vs 32.0 ± 9.0 hours, p < 0.001). However, the operation time, drainage tube placement time, post-operative hospital stay in the RARLA group were significantly longer compared with the RLA group (149.6 ± 53.4 mins vs 118.7 ± 41.2 mins, p = 0.003; 4.9 ± 2.0 days vs 3.6 ± 1.1 days, p = 0.004; 6.4 ± 1.8 days vs 4.6 ± 1.6 days, p < 0.001). The hospitalization expense in the RARLA group is significantly higher than that in the RLA group (59284 ± 8724 RMB¥ vs 39785 ± 10126 RMB¥, p < 0.001). We found that there was no significant difference in the incidence of postoperative complications between the two groups. However, the pathological types of the two groups were significantly different. Patients in the RLA group had a higher proportion of adrenocortical adenoma, while patients in the RARLA group had a higher proportion of pheochromocytoma.

CONCLUSION

Compared with traditional laparoscopic adrenalectomy, robot-assisted laparoscopic adrenalectomy can significantly reduce intraoperative blood loss and accelerate postoperative gastrointestinal recovery. It is committed to studying how to reduce the hospitalization time and hospitalization cost of RARLA, which can make RARLA more widely used.

Minimally invasive techniques in benign and malignant adrenal tumors

Minimally invasive adrenalectomy has become the main treatment modality for most adrenal lesions. Both laparoscopic transabdominal and retroperitoneoscopic approaches are safe and feasible options, each with respective advantages, including better surgical outcomes, fewer complications, and faster recovery over open adrenalectomy. While open surgery remains a valid modality in treatment of adrenocortical cancer in the presence of some findings such as invasion, robotic platforms, and minimally invasive surgery have gained popularity as technology continues to evolve. Organ preservation during adrenalectomy is feasible in some conditions to prevent adrenal insufficiency. Ablative technologies are increasingly utilized in benign and malignant tumors, including the adrenal gland, with various outcomes. A multidisciplinary team, an experienced surgeon, and a high-volume center are recommended for any surgical approaches and management of adrenal lesions. This review article evaluated recent findings and current evidence on minimally invasive adrenalectomy.

[Minimally invasive techniques in adrenal gland surgery]

Today, adrenalectomy can be performed by a variety of laparoscopic and retroperitoneoscopic approaches. Of particular importance are the lateral transperitoneal and the posterior retroperitoneoscopic access routes. Comparative studies of transperitoneal and retroperitoneal procedures still demonstrate heterogeneous results. Nevertheless, retroperitoneal access techniques seem to enable less postoperative pain and a faster recovery. Robotic procedures are gaining in popularity but the final importance cannot yet be determined. All minimally invasive techniques are considered to be so safe and reliable that open approaches are only justified in exceptional cases.

Robotic Adrenalectomy Using the da Vinci SP Robotic System: Technical Feasibility Comparison with Single-Port Access Using the da Vinci Multi-arm Robotic System

BACKGROUND

Laparoscopic adrenalectomy is the gold standard for adrenal tumor; however, robotic adrenal surgery has gained interest recently. For minimally invasive surgeries, we first reported on robotic adrenalectomy using a single-port access performed using the da Vinci multi-arm robotic system (RA-SA) in 2011. Since its introduction in 2018, we first performed robotic adrenalectomy using the da Vinci SP robotic system in 2020.

OBJECTIVE

We aimed to introduce the novel single-port robotic system (RA-SP) for adrenalectomy and evaluate its technical feasibility by comparing it with the surgical outcomes of patients who underwent robotic adrenalectomy using the RA-SA.

METHODS

Eight patients who underwent robotic adrenalectomy using the RA-SP from February 2020 to June 2021 were compared with 11 patients who underwent RA-SA from 2011 to 2015 by a single surgeon.

RESULTS

The two groups were similar in age, sex, body mass index, type of operation, and final pathologic diagnosis. Despite no significant differences, RA-SP resulted in moderately less mean operation time, estimated blood loss, and length of hospitalization.

CONCLUSIONS

The Da Vinci SP robotic system is a novel, safe, and feasible technique to improve the convenience of operation and cosmetic effect for adrenalectomy.

Cancer risk in adrenalectomy: are adrenal lesions equal or more than 4 cm a contraindication for laparoscopy?

Background

Some authors consider adrenal lesions size of less than 4 cm as a positive cut-off limit to set the indications for minimally invasive surgery due to a lower risk of malignancy. Aim of this study is to report the risk of cancer for adrenal lesions measuring 4 cm or more in diameter, assessed as benign at preoperative workup (primary outcome), and to evaluate the feasibility and safety of laparoscopic adrenalectomy (LA) in these cases (secondary outcome).

Methods

From January 1994 to February 2019, 579 patients underwent adrenalectomy. Fifty patients with a preoperative diagnosis of primary adrenal cancer or metastases were excluded. The remaining 529 patients were included and divided in five subgroups based on adrenal lesion size at definitive histology: group A, 4–5.9 cm (137 patients); group B, 6–7.9 cm (64 patients); group C, 8–9.9 cm (13 patients); group D, ≥ 10 cm (11 patients); group E, < 4 cm (304 patients). Each group was further divided based on diagnosis of benign or malignant lesions at definitive histology.

Results

Four (2.9%) malignant lesions were observed in group A, 5 (7.8%) in group B, 2 (15.4%) in Groups C and D (18.2%) and 13 (4.3%) in Group E. Comparing the cancer risk among the groups, no statistically significant differences were observed. Operative time increased with increasing lesion size. However, no statistically significant differences were observed between benign and malignant lesions in each group comparing operative time, conversion and complication rates, postoperative hospital stay and mortality rate.

Conclusions

Adrenal lesions measuring 4 cm or more in diameter are not a contraindication for LA neither in terms of cancer risk nor of conversion and morbidity rates, even if the operative time increases with increasing adrenal lesion diameter. Further prospective studies with a larger number of patients are required to draw definitive conclusions.

Minimally Invasive Adrenal Surgery

Since the introduction of minimally invasive surgery, laparoscopic adrenalectomy has become the main treatment option for adrenal masses. Various studies have reported that laparoscopic adrenalectomy showed fewer postoperative complications and faster recovery than conventional open adrenalectomy. Laparoscopic adrenalectomy can be performed through either the transperitoneal approach or the retroperitoneoscopic approach, which are widely used in most adrenal surgical procedures. Furthermore, with the development of minimally invasive surgery, organ-sparing adrenalectomy has recently emerged as a way to conserve functional adrenal gland tissue. According to recent data, organ-sparing adrenalectomy shows promising surgical, functional, and oncological outcomes including less intraoperative blood loss, maintenance of adrenal function, and low recurrence. Partial adrenalectomy was initially proposed for bilateral adrenal tumors in patients with hereditary disease to avoid chronic adrenal insufficiency. However, it has also gained popularity for the treatment of unilateral adrenal disease involving a small adrenal tumor because even patients with a unilateral adrenal gland may develop adrenal insufficiency in stressful situations. Therefore, partial adrenalectomy has become increasingly common to avoid lifelong steroid replacement and recurrence in most cases, especially in bilateral adrenal disease. This review article evaluates the current evidence on minimally invasive adrenalectomy and organ-preserving partial adrenalectomy.