Cystic adrenal lesions: CT features

Adrenal Neoplasms: Lessons from Adrenal Multidisciplinary Tumor Boards

The radiologic diagnosis of adrenal disease can be challenging in settings of atypical presentations, mimics of benign and malignant adrenal masses, and rare adrenal anomalies. Misdiagnosis may lead to suboptimal management and adverse outcomes. Adrenal adenoma is the most common benign adrenal tumor that arises from the cortex, whereas adrenocortical carcinoma (ACC) is a rare malignant tumor of the cortex. Adrenal cyst and myelolipoma are other benign adrenal lesions and are characterized by their fluid and fat content, respectively. Pheochromocytoma is a rare neuroendocrine tumor of the adrenal medulla. Metastases to the adrenal glands are the most common malignant adrenal tumors. While many of these masses have classic imaging appearances, considerable overlap exists between benign and malignant lesions and can pose a diagnostic challenge. Atypical adrenal adenomas include those that are lipid poor; contain macroscopic fat, hemorrhage, and/or iron; are heterogeneous and/or large; and demonstrate growth. Heterogeneous adrenal adenomas may mimic ACC, metastasis, or pheochromocytoma, particularly when they are 4 cm or larger, whereas smaller versions of ACC, metastasis, and pheochromocytoma and those with washout greater than 60% may mimic adenoma. Because of its nonenhanced CT attenuation of less than or equal to 10 HU, a lipid-rich adrenal adenoma may be mimicked by a benign adrenal cyst, or it may be mimicked by a tumor with central cystic and/or necrotic change such as ACC, pheochromocytoma, or metastasis. Rare adrenal tumors such as hemangioma, ganglioneuroma, and oncocytoma also may mimic adrenal adenoma, ACC, metastasis, and pheochromocytoma. The authors describe cases of adrenal neoplasms that they have encountered in clinical practice and presented to adrenal multidisciplinary tumor boards. Key lessons to aid in diagnosis and further guide appropriate management are provided. © RSNA, 2023 Online supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center.

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.

Giant adrenal pseudocyst removed using robot-assisted surgery

Introduction

Adrenal cysts are relatively rare and often asymptomatic. Surgical treatment is indicated for symptomatic cases with cysts >6 cm, suspected bleeding, and those that cannot be distinguished from malignant illness based on imaging findings. There have often been cases of giant cysts that were difficult to treat using laparoscopic surgery.

Case presentation

A 39-year-old woman presented with fever and upper abdominal pain. Abdominal computed tomography and magnetic resonance imaging revealed a 95 × 80-mm left adrenal cyst. As malignant disease could not be ruled out, and the patient was symptomatic, we opted for robot-assisted left adrenalectomy. The pathological findings indicated an adrenal pseudocyst.

Conclusions

This is the second report of the successful robot-assisted removal of a giant adrenal cyst.

Clinical, imaging and biochemical presentation of cystic pheochromocytomas

OBJECTIVE

Cystic adrenal mass is a rare imaging presentation of pheochromocytoma. We aimed to describe the clinical, biochemical and imaging characteristics of patients with cystic pheochromocytoma.

DESIGN

Single-centre, retrospective study, 2000-2020.

PATIENTS

Consecutive patients with cystic pheochromocytoma were identified from our institutional pathology and adrenal tumour database.

RESULTS

Of the 638 patients with pheochromocytomas, 21 (3.2%) had cystic pheochromocytomas (median age: 57 years, 57% women). Most pheochromocytomas were discovered incidentally (57%) or due to symptoms of catecholamine excess (24%). The median tumour size was 6.4 cm. On imaging, cystic pheochromocytomas were round or oval (90%), heterogeneous lesions (86%) with a thick solid rim (median rim thickness 13.9 mm, unenhanced computed tomography (CT) attenuation 40 Hounsfield units (HU), venous-phase CT attenuation 83 HU), and a median cystic component of 40% (unenhanced CT attenuation 17.6 HU, venous-phase CT attenuation 20.4 HU), and rarely with calcifications (15%). All 20 patients with biochemical testing had functioning tumours (adrenergic in 80%, noradrenergic in 20%). Total urinary metanephrine excretion correlated with the volume of the solid component (R2  = .75, p < .0001) but not the cystic component (R2  = .04, p = .4386). All patients underwent adrenalectomy (48% laparoscopic, 52% open), and the median duration of hospital stay was 4 days.

CONCLUSIONS

Cystic pheochromocytomas are rare, large tumours with a phenotypic appearance that can masquerade as other adrenal cystic lesions. The degree of biochemical abnormality in cystic pheochromocytomas is associated with the volume of the solid component. All patients with adrenal cysts that have a solid component or an unenhanced attenuation >10 HU should undergo biochemical testing for pheochromocytoma.

Multimodality imaging of adrenal gland pathologies: A comprehensive pictorial review

The assessment of acute abdominal and pelvic emergencies typically involves a multimodal approach consisting of plain radiographs, ultrasound, computed tomography (CT), and rarely magnetic resonance imaging (MRI). Although MRI is not traditionally employed in acute care settings, there are several instances in which MRI provides superior functional and prognostic information. In this manuscript, we highlight multimodal findings of adrenal gland emergencies: Hemorrhage, infarction, and infection. The purpose of our study is to highlight significant findings in various modalities, including CT, MRI, ultrasound, and PET/CT. Due to the scarcity of published data and limited clinical use, primary ultrasound findings are limited in our multimodal review. In conclusion, we find that synergistic use of CT, MRI, and functional imaging provides an effective tool for evaluation and management of adrenal pathology.

Mimics, pitfalls, and misdiagnoses of adrenal masses on CT and MRI

Due to the widespread use of imaging, incidental adrenal masses are commonly encountered. A number of pitfalls can result in misdiagnosis of these lesions, including inappropriate choice of imaging technique, presence of pseudolesions, and overlap of imaging features of different adrenal lesions. This article explores the potential pitfalls in imaging of the adrenal glands, on computed tomography and magnetic resonance imaging, that can lead to misinterpretation. Clues to correct diagnoses are provided to evade potential misinterpretation.

Calcified Adrenal Lesions: Pattern Recognition Approach on Computed Tomography With Pathologic Correlation

Incidental adrenal lesions are found in 2% to 10% of the population. The presence and pattern of calcifications, in conjunction with other clinical and imaging features, such as soft tissue attenuation, enhancement, and laterality, can aid in narrowing a differential diagnosis, thereby preventing unnecessary biopsies and avoiding delays in management. Calcified adrenal lesions can be categorized under the clinical and laboratory headings of normal adrenal function, hyperfunctioning adrenal tissue, and adrenal insufficiency. In this review, we provide an algorithmic approach to assessing calcified adrenal nodules with correlative radiologic findings.

Incidentally found cystic lymphangioma of the adrenal gland in an elderly male cadaver

Adrenal cystic lymphangiomas are extremely rare entities that are often identified incidentally, with less than 60 cases reported to date. We found a protruding ovoid mass consisting of a multiloculated cystic lesion within right adrenal gland in the cadaver of a 75-year-old Korean man. The epithelial cells lining the adrenal cyst were diffusely positive for cluster of differentiation 31 and podoplanin, and negative for pan-cytokeratin. The histopathological diagnosis confirmed a cystic lymphangioma arising from the adrenal gland. Post-mortem findings of the present case are discussed based on the clinicopathological features of adrenal cystic lymphangiomas.

Simple adrenal cyst masquerading clinically silent giant cystic pheochromocytoma

Pheochromocytoma (PCC) may present as a cystic or solid tumour. Cystic PCCs are difficult to differentiate from simple cysts in the absence of classic symptoms of PCCs. Cystic nature develops due to intralesional bleeding and necrosis. We present a case of young man without any comorbidity who was diagnosed as a simple adrenal cyst and planned for laparoscopic excision but found to be functional PCC during the time of surgery only. The patient was managed with extensive monitoring and use of multiple drugs to control blood pressure. Surgery was completed without any complication laparoscopically and postoperative period was also uneventful. Histopathology confirmed the diagnosis of cystic PCC. Our case also shows the importance of functional imaging like metaiodobenzylguanidine (MIBG) scan in doubtful cases of adrenal cysts when other biochemical markers are unremarkable to diagnosis. We emphasise the importance of meticulous preparation for any intraoperative disasters even for apparently simple adrenal cyst.

Multi-detector computed tomography in the diagnosis and characterization of adrenal gland traumatic injuries

Adrenal gland injuries after a blunt abdominal trauma are rare events and represent important indicators for severe trauma. Multidetector CT evolution with high volumetric resolution and fast acquisition with the use of multiplanar reformatted (MPR) visualization allows for an accurate and fast diagnosis of the adrenal gland for post-traumatic pathologies. While, before its introduction the diagnosis was made mainly postmortem or during surgery. Adrenal injuries are unilateral up to 90% of the cases involving most commonly the right gland; thoracoabdominal organs injuries are often also associated. Bilateral adrenal lesions are asymptomatic, potentially leading to the development of acute adrenal insufficiency. The purpose of the present review was to determine the prevalence, the mechanism of injury and the different CT appearances of adrenal trauma. Prognosis and management of adrenal injury will also be reviewed.

Practical Approach to Adrenal Imaging

Various pathologies can affect the adrenal gland. Noninvasive cross-sectional imaging is used for evaluating adrenal masses. Accurate diagnosis of adrenal lesions is critical, especially in cancer patients; the presence of adrenal metastasis changes prognosis and treatment. Characterization of adrenal lesions predominantly relies on morphologic and physiologic features to enable correct diagnosis and management. Key diagnostic features to differentiate benign and malignant adrenal lesions include presence/absence of intracytoplasmic lipid, fat cells, hemorrhage, calcification, or necrosis and locoregional and distant disease; enhancement pattern and washout values; and lesion size and stability. This article reviews a spectrum of adrenal pathologies.

Imaging of Nonmalignant Adrenal Lesions in Children

The adrenal glands in children can be affected by a variety of benign lesions. The diagnosis of adrenal lesions can be challenging, but assessment of morphologic changes in correlation with the clinical presentation can lead to an accurate diagnosis. These lesions can be classified by their cause: congenital (eg, discoid adrenal gland, horseshoe adrenal gland, and epithelial cysts), vascular and/or traumatic (eg, adrenal hemorrhage), infectious (eg, granulomatous diseases), enzyme deficiency disorders (eg, congenital adrenal hyperplasia [CAH] and Wolman disease), benign neoplasms (eg, pheochromocytomas, ganglioneuromas, adrenal adenomas, and myelolipomas), and adrenal mass mimics (eg, extralobar sequestration and extramedullary hematopoiesis). Multimodality cross-sectional imaging helps to define the origin, extent, and relationship of these lesions to adjacent structures, as well as to guide treatment management. The anatomic and functional imaging modalities used to evaluate pediatric adrenal lesions include ultrasonography, computed tomography (CT), magnetic resonance imaging, and iodine 123 metaiodobenzylguanidine scintigraphy. Identifying the imaging features of nonmalignant adrenal lesions is helpful to distinguish these lesions from malignant adrenal neoplasms. Identifying characteristic imaging findings (eg, enlarged adrenal glands, with cerebriform surface, and stippled echogenicity in CAH; a T2-hyperintense mass with avid contrast enhancement in pheochromocytoma; low CT attenuation [<10 HU] and signal intensity drop on opposed-phase chemical shift images in adenoma; and enhancing suprarenal mass supplied by a systemic feeding artery in extralobar sequestration) can aid in making the correct diagnosis. In addition, clinical features (eg, ambiguous genitalia in CAH and hypertension in pheochromocytoma) can also guide the radiologist toward the correct diagnosis. ^©RSNA, 2017.

[Vascular adrenal cyst causing difficult to control high blood pressure]

Hypertension is a prevalent disease in developed countries. Adrenal masses, and especially adrenal cysts, are a rare and usually asymptomatic finding, which can go unnoticed or be detected as incidental findings in imaging tests. These circumstances make the multidisciplinary approach mandatory. The case is presented on a 72 year-old woman with uncontrolled high blood pressure referred to the Urology Department due to the incidental finding of a right retroperitoneal mass. A functional and imaging study was performed, establishing a diagnosis of adrenal cyst causing hypertensive symptoms. A literature search was performed in order to assess diagnostic and therapeutic approaches. With the diagnosis of adrenal cyst causing uncontrolled high blood pressure, a right laparoscopic adrenalectomy was performed. After surgery the patient has maintained blood pressure within the normal range. A multidisciplinary approach is necessary for the management of rare diseases. The surgical approach, if possible, should be laparoscopic.

Radiology of the adrenal incidentalomas. Review of the literature

The term "adrenal incidentaloma" is a radiological term. Adrenal incidentalomas are adrenal tumors discovered in an imaging study that has been obtained for indications exclusive to adrenal conditions (Udelsman 2001; Linos 2003; Bulow et al. 2006; Anagnostis et al. 2009). This definition excludes patients undergoing imaging testing as part of staging and work-up for cancer (Grumbach et al. 2003; Anagnostis et al. 2009). Papierska et al. (2013) have added the prerequisite that the size of a tumor must be "greater than 1cm in diameter", in order to be called incidentaloma. Although in the most cases these masses are non-hypersecreting and benign, they still represent an important clinical concern because of the risk of malignancy or hormone hyperfunction (Barzon et al. 2003). Th e adrenal tumors belong to the commonest incidental findings having been discovered (Kanagarajah et al. 2012).

Adrenal Imaging

Cross-sectional imaging can make a specific diagnosis in lesions, such as myelolipomas, cysts, and hemorrhage, and is often sufficient to distinguish benign from malignant adrenal processes. CT and MRI are useful studies to identify pheochromocytomas and cortisol-secreting or androgen-secreting tumors. In patients with primary aldosteronism, adrenal venous sampling remains the most accurate localizing study and should be performed in all patients older than 35. Radiolabeled isotope studies serve as second-line diagnostic tests for malignant adrenal tumors, primary or metastatic, as well as for pheochromocytoma. Nuclear imaging studies should follow a robust hormonal diagnosis and be correlated with findings on cross-sectional imaging.

Management of Adrenal Masses

An adrenal mass can be either symptomatic or asymptomatic in the form of adrenal incidentalomas (AIs) in up to 8 % in autopsy and 4 % in imaging series. Once a diagnosis of adrenal mass is made, we need to differentiate whether it is functioning or nonfunctioning, benign, or malignant. In this article, we provide a literature review of the diagnostic workup including biochemical evaluation and imaging characteristics of the different pathologies. We also discuss the surgical strategies with laparoscopy as the mainstay with partial adrenalectomy in select cases and adrenalectomy in large masses. Follow-up protocol of AIs and adrenocortical carcinoma is also discussed.

Contemporary imaging of incidentally discovered adrenal masses

Adrenal lesions are routinely encountered incidentally in clinical practice. Although most of these lesions are benign, malignancy needs to be excluded. Therefore, the initial clinical workup is to exclude aggressive characteristics suggesting malignancy and to identify characteristics predictive of the most common benign lesion, an adrenal adenoma. Predicting a benign adenoma using a variety of imaging modalities has been widely studied using unenhanced computed tomography (CT), contrast enhanced CT, and magnetic resonance (MR) imaging. This review article describes the currently used imaging protocols and clinical interpretation criteria of common adrenal lesions. An adenoma can be predicted if a homogenous soft tissue adrenal mass demonstrates low attenuation (upper threshold value of 10 Hounsfield Units) on unenhanced CT, demonstrates an absolute enhancement washout of ≥ 60% and/or relative enhancement washout of ≥ 40% on adrenal washout contrast enhanced CT, or demonstrates signal loss in opposed-phased MR imaging. If an adrenal adenoma cannot be predicted based upon these criteria, the lesion should be evaluated for other imaging characteristics that suggest a specific pathology, such as an adrenal cyst or myelolipoma. Although nonspecific and with limitations, 18F-fluorodeoxyglucose (FDG) PET/CT has a potential role for differentiating benign from malignant lesions based upon the amount of radiopharmaceutical uptake with malignant lesions generally having greater uptake. If clinical and/or hormonal screening suggests a pheochromocytoma, consideration can be given to 18F-dihydroxyphenylalanine (DOPA) or 123I-metaiodobenzylguanidine (MIBG) in addition to CT and MR. Finally, this review proposes a diagnostic work-up strategy for routine use in clinical practice.

Practical Approach to Adrenal Imaging

Various pathologies can affect the adrenal gland. Noninvasive cross-sectional imaging is used for evaluating adrenal masses. Accurate diagnosis of adrenal lesions is critical, especially in cancer patients; the presence of adrenal metastasis changes prognosis and treatment. Characterization of adrenal lesions predominantly relies on morphologic and physiologic features to enable correct diagnosis and management. Key diagnostic features to differentiate benign and malignant adrenal lesions include presence/absence of intracytoplasmic lipid, fat cells, hemorrhage, calcification, or necrosis and locoregional and distant disease; enhancement pattern and washout values; and lesion size and stability. This article reviews a spectrum of adrenal pathologies.

Adrenal Lymphangioma Masquerading as a Catecholamine Producing Tumor

Objective. To report the unusual case of an adrenal lymphangioma presenting in a patient with an adrenal cystic lesion and biochemical testing concerning for pheochromocytoma. The pertinent diagnostic and imaging features of adrenal lymphangiomas are reviewed. Methods. We describe a 59-year-old patient who presented with hyperhidrosis and a 2.2 by 2.2 cm left adrenal nodule. Biochemical evaluation revealed elevated plasma-free normetanephrine, urine normetanephrine, urine vanillylmandelic acid, and urine norepinephrine levels. Elevated plasma norepinephrine levels were not suppressed appropriately with clonidine administration. Results. Given persistent concern for pheochromocytoma, the patient underwent adrenalectomy. The final pathology was consistent with adrenal lymphangioma. Conclusions. Lymphangiomas are benign vascular lesions that can very rarely occur in the adrenal gland. Imaging findings are generally consistent with a cyst but are nonspecific. Excluding malignancy in patients presenting with adrenal cysts can be difficult. Despite its benign nature, the diagnosis of adrenal lymphangioma may ultimately require pathology.

Should we use CT or MRI for detection and characterization of benign adrenal lesions?

OBJECTIVES

Computed tomography (CT) and magnetic resonance imaging (MRI) are the main imaging modalities used for analysis of adrenal lesions. We compared the ability of CT and MRI to detect and characterize benign adrenal lesions.

PATIENTS AND METHODS

Unenhanced abdominal CT and MRI were performed in 16 patients (age range 39-77), and reviewed by a radiologist with 6years of experience in abdominal imaging. The presence, number, size and structure of each mass were analyzed and compared between the two modalities.

RESULTS

There were 18 adrenal masses in 11 patients, four patients had adrenal hyperplasia (AH), whereas one patient had left-sided AH and right-sided adenoma. Ten masses were≥2cm in diameter, and were perfectly depicted using CT and all MRI techniques. There were nine masses with diameter<2cm detected by CT, three of them were missed using MRI. AH was detected in five patients using CT, but its mild form was missed in one patient using MRI. Four masses with attenuation values of>10Hounsfield units could not be characterized using unenhanced CT, but three of them were characterized using MRI.

CONCLUSION

CT has higher sensitivity for detection of small adrenal tumours and adrenal hyperplasia than MRI. MRI is an important tool in characterization of adrenal masses that could not be characterized using unenhanced CT.

All Those Liver Masses are not Necessarily from the Liver: A Case of a Giant Adrenal Pseudocyst Mimicking a Hepatic Cyst

BACKGROUND

Most abdominal cysts, including adrenal pseudocysts, are benign and asymptomatic. Rapid enlargement, hemorrhage, infection, rupture with leakage of cyst contents, or pressure on adjacent organs can cause symptoms. Although usually diagnosed incidentally on imaging, determining the origin of a cyst can sometimes be challenging. In these situations, surgical excision and pathological analysis is crucial to diagnosis and management. We report here a case of a giant symptomatic adrenal pseudocyst that closely mimicked a hepatic cyst at presentation.

CASE REPORT

A 50-year-old man, with a history of an incidentally detected hepatic cyst, presented with severe abdominal pain, fevers, leukocytosis, and mildly abnormal liver function tests. CT scan revealed a large well defined cystic space-occupying lesion within the liver, with findings suggesting cyst rupture and possible infection. Early laparotomy was performed, and the origin was determined intraoperatively to be right adrenal, which was later confirmed by pathology.

CONCLUSIONS

Contrast-enhanced CT scan is the criterion standard for evaluation for abdominal cystic masses. Precise diagnosis of a giant abdominal cyst can be challenging. Surgery is both diagnostic and curative in such situations. We also discuss the specific situations in which surgery should be considered in cases of adrenal cystic masses.

Metabolic and anatomic characteristics of benign and malignant adrenal masses on positron emission tomography/computed tomography: a review of literature

PET/CT with (18)F-fluorodeoxyglucose (FDG) or using different radiocompounds has proven accuracy for detection of adrenal metastases in patients undergoing cancer staging. It can assist the diagnostic work-up in oncology patients by identifying distant metastases to the adrenal(s) and defining oligometastatic disease that may benefit from targeted intervention. In patients with incidentally discovered adrenal nodules, so-called adrenal "incidentaloma" FDG PET/CT is emerging as a useful test to distinguish benign from malignant etiology. Current published evidence suggests a role for FDG PET/CT in assessing the malignant potential of an adrenal lesion that has been 'indeterminately' categorized with unenhanced CT, adrenal protocol contrast-enhanced CT, or chemical-shift MRI. FDG PET/CT could be used to stratify patients with higher risk of malignancy for surgical intervention, while recommending surveillance for adrenal masses with low malignant potential. There are caveats for interpretation of the metabolic activity of an adrenal nodule on PET/CT that may lead to false-positive and false-negative interpretation. Adrenal lesions represent a wide spectrum of etiologies, and the typical appearances on PET/CT are still being described, therefore our goal was to summarize the current diagnostic strategies for evaluation of adrenal lesions and present metabolic and anatomic appearances of common and uncommon adrenal lesions. In spite of the emerging role of PET/CT to differentiate benign from malignant adrenal mass, especially in difficult cases, it should be emphasized that PET/CT is not needed for most patients and that many diagnostic problems can be resolved by CT and/or MR imaging.

Imaging of the adrenal gland lesions

With the steep increase in the use of cross-sectional imaging in recent years, the incidentally detected adrenal lesion, or "incidentaloma", has become an increasingly common diagnostic problem for the radiologist, and a need for an approach to classifying these lesions as benign, malignant or indeterminate with imaging has spurred an explosion of research. While most incidentalomas represent benign disease, typically an adenoma, the possibility of malignant involvement of the adrenal gland necessitates a reliance on imaging to inform management decisions. In this article, we review the literature on adrenal gland imaging, with particular emphasis on computed tomography, magnetic resonance imaging, and photon-emission tomography, and discuss how these findings relate to clinical practice. Emerging technologies, such as contrast-enhanced ultrasonography, dual-energy computed tomography, and magnetic resonance spectroscopic imaging will also be briefly addressed.

Adrenal Gland Lymphangiomas

Lymphangiomas of the adrenal glands (ALs) are benign vascular lesions. Approximately, 53 cases have been reported in the literature. The current study reviews and analyzes the clinical and pathologic features of all reported ALs and additionally illustrates a typical case of adrenal lymphangioma (AL). In order to perform the review analysis, a search of the international literature for ALs in adults was conducted. Thirty-eight related articles were found. Clinical and pathological information were obtained for all the reported cases and a database was created. ALs were detected more frequently in women than men. The mean age of occurrence was 39.5 years, while their mean size was 8.86 cm. Fifty-nine percent of ALs were right-sided. Size and localization were responsible for the presenting symptoms, though 30.4 % were asymptomatic. Diagnosis was made postoperatively in all cases by histological results. ALs are rare and benign lesions. They usually present as an incidental finding after abdominal imaging. The diagnosis is made after the surgical removal by histological and immunohistochemical examinations.

Postsurgical large adrenal cyst recurrence: treatment by means of percutaneous alcohol ablation

We describe a case of a 28-year-old man who presented with symptomatic, right-sided, large adrenal cyst recurrence 9 months after laparoscopic decortication. Final treatment was achieved by means of percutaneous aspiration and ethanol ablation. On 6-month follow-up the patient was asymptomatic and the cyst remained minimised. In our opinion, percutaneous treatment with alcohol ablation of primary benign symptomatic or recurrent uncomplicated adrenal cysts should be considered as an effective alternative method when patients are frail or surgery fails to resolve the problem.

Cystic adrenal lesions: clinical and surgical management. The experience of a referral centre

BACKGROUND

Cystic adrenal lesions (CALs) represent a rare entity having heterogeneity in etiology and clinical manifestations. Due to their very low incidence and heterogeneity in clinical aspects, many controversials still exist about their management.

METHODS

From 1984 to 2012, 21 patients (7 M, 14 F, mean age 48.2 years) underwent adrenalectomy for CALs. 9 patients suffered from hypertension, and 7 were affected by thyroid disorders.

RESULTS

4 patients presented with vague abdominal pain, while in 17 patients the CAL was incidentally identified during imaging examinations. All patients underwent evaluation of adrenal functionality and imaging study. We found 1 case of cystic pheochromocytoma (confirmed by urinary and blood sampling, and MIBG-scan). All patients underwent adrenalectomy (open approach in the first 10 patients treated from 1984 to 1996, laparoscopic lateral transabdominal approach in the other 11 cases). Indication to surgery included: size over 4.5 cm in 16 cases, suspected malignancy at imaging evaluation (not confirmed by histology) in 4 cases, cystic pheochromocytoma in 1 case. Histology revealed 11 endothelial cysts, 3 pseudocysts, 6 epithelial cysts and 1 cystic pheochromocytoma.

CONCLUSIONS

The presence of CAL, even asymptomatic, requires complete endocrinological evaluation and imaging study. In the presence of large size, endocrine activity or any suspicion of malignancy, patients must be referred to surgery.

Imaging of nontraumatic adrenal hemorrhage

OBJECTIVE

The purpose of this pictorial essay is to review the imaging findings of acute, chronic, and tumor-related nontraumatic adrenal hemorrhage.

CONCLUSION

Rapid development or evolution of a nonenhancing adrenal mass or masses with an adreniform shape or high T1 signal intensity on MR images of a patient under stress or with a bleeding diathesis, including anticoagulant use, suggests acute adrenal hemorrhage. Chronic hemorrhage appears as a thin-walled pseudocyst or atrophy. Imaging findings that may indicate underlying tumor include intralesional calcification, enhancement, and hypermetabolic activity on PET images.

Adrenal imaging: a comprehensive review

The discovery of an incidental adrenal mass (adrenal incidentaloma) continues to rise with the increasing use of cross-sectional imaging. Although most adrenal lesions are benign and asymptomatic, radiologists should guide evaluation of these lesions, whether benign or malignant. This article reviews the various imaging techniques used to evaluate adrenal masses and their relative strengths and weaknesses. It focuses on the most prevalent adrenal pathologies and their typical imaging characteristics, and concludes with a brief discussion of developing techniques, including diffusion-weighted imaging and dual-energy CT.

Three uncommon adrenal incidentalomas: a 13-year surgical pathology review

BACKGROUND

The discovery of adrenal incidentalomas due to the widespread use of sophisticated abdominal imaging techniques has resulted in an increasing trend of adrenal gland specimens being received in the pathology laboratory. In this context, we encountered three uncommon adrenal incidentalomas.The aim of this manuscript is to report in detail the three index cases of adrenal incidentalomas in the context of a 13-year retrospective surgical pathology review.

METHODS

The three index cases were investigated and analyzed in detail with relevant review of the English literature as available in PubMed and Medline. A 13-year retrospective computer-based histopathological surgical review was conducted in our laboratory and the results were analyzed in the context of evidence-based literature on adrenal incidentalomas.

RESULTS

A total of 94 adrenal specimens from incidentalomas were identified, accounting for 0.025% of all surgical pathology cases. In all 76.6% were benign and 23.4% were malignant. A total of 53 females (56.4%) and 41 males (43.6%) aged 4 to 85 years were identified. The benign lesions included cortical adenoma (43.1%), pheochromocytoma (29.3%) and inflammation/fibrosis/hemorrhage (8.3%). Metastatic neoplasms were the most common malignant lesions (50%) followed by primary adrenocortical carcinomas (31.8%) and neuroblastoma (13.6%). These cases were discovered as adrenal incidentalomas that led to surgical exploration.The three index cases of adrenal incidentalomas with unusual pathologies were encountered that included (a) adrenal ganglioneuroma, (b) periadrenal schwannoma and (c) primary adrenal pleomorphic leiomyosarcoma. These cases are discussed, with a literature and clinicopathological review.

CONCLUSIONS

Adrenal lesions are uncommon surgical specimens in the pathology laboratory. However, higher detection rates of adrenal incidentalomas aided by the ease of laparoscopic adrenalectomy has resulted in increased adrenal surgical specimens leading to unsuspected diagnostic and management dilemmas. Accurate pathological identification of common and uncommon adrenal incidentalomas is essential for optimal patient management.

Radiological evaluation of adrenal incidentalomas: current methods and future prospects

Incidental adrenal lesions are very common. Computed tomography (CT), magnetic resonance imaging (MRI) and positron emission tomography (PET) all have a role to play in characterizing adrenal lesions. The purpose of this review is to discuss the rationale behind both established and emerging imaging techniques. We also discuss how to follow up incidentally found lesions.

Adrenal masses in children

Adrenal tumors include those of neural and cortical origin. Although most neuroblastomas present as abdominal masses, pheochromocytomas and cortical tumors usually present with endocrine dysfunction. Although imaging may not be able to differentiate benign lesions from malignant tumors, or whether they arise in the adrenal medulla or cortex, imaging is useful in determining the extent of the lesion and its relation to surrounding anatomic structures, particularly to vessels. Regardless of what imaging modality is used, meticulous attention to technique is required.

A giant adrenal pseudocyst presenting with right hypochondralgia and fever: a case report

Introduction

Adrenal pseudocysts are rare cystic masses that arise from the adrenal gland and which are usually non-functional and asymptomatic. Adrenal pseudocysts consist of a fibrous wall without an epithelial or endothelial lining. We report the case of a patient with a giant adrenal pseudocyst presenting with right hypochondralgia and high fever.

Case presentation

A 52-year-old Japanese man was admitted with right hypochondralgia and a chill. Abdominal computed tomography revealed a well-defined cystic mass measuring 19 cm which was located in the right adrenal region and the contents of which were not enhanced with contrast medium. Abdominal ultrasonography revealed a heterogeneously hypo-echoic lesion with a peripheral high-echoic rim. Serum hormonal levels were almost normal. Despite treatment with antibiotics, the high fever persisted. Based on these findings, we made a preoperative diagnosis of a right adrenal cyst with infection. However, the possibility of malignancy still remained. The patient underwent laparotomy and right adrenal cyst excision with partial hepatectomy in order to relieve the symptoms and to confirm an accurate diagnosis. Histological examination revealed an adrenal pseudocyst with infection. His condition improved soon after the operation.

Conclusion

We report a case of a giant adrenal pseudocyst with infection. Surgery is required for symptomatic cases in order to relieve the symptoms and in cases of uncertain diagnosis.

Incidental and metastatic adrenal masses

In the last decades discoveries of adrenal masses incidentally during the course of diagnostic procedures for unrelated disorders (incidentalomas) have become progressively more frequent. The clinician in this position must answer two main questions: Is the mass benign or malignant?, and To what extent is the adrenal secretion altered? To come to a clinical decision, several diagnostic tools need to be engaged, starting with an accurate and correct radiological evaluation and a hormonal assessment of the adrenal function. When necessary, other diagnostic procedures such as functional imaging and fine-needle biopsy (FNB) can be considered in selected cases. Surgical removal is recommended for clinically relevant hypersecretory masses, as well as for masses suspected to be malignant. Most frequently, adrenal incidentalomas (AIs) are represented by benign cortical adenomas, a subset of which causes a mild hypercortisolism, known as subclinical Cushing's syndrome (SCS). The criteria to define this syndrome, as well as its treatment, are still debated and controversial. AIs that are not surgically removed should be re-examined in time to exclude a supervening increase in size or function. Follow-up criteria have not been established. Laparoscopic surgery is the recommended procedure to remove benign masses. The surgical procedure for adrenal malignancies is still debated.

Adrenal imaging

OBJECTIVE

Adrenal nodules are frequently encountered on current high-resolution imaging, and accurate characterization of such lesions is critical for appropriate patient care. Our article highlights how imaging techniques such as CT densitometry, CT washout characteristics, chemical shift MRI, PET, and PET/CT help characterize most adrenal lesions. We focus on these techniques as well as specifically, because of space constraints, the varied imaging appearances of adrenocortical carcinoma, pheochromocytoma, and lymphoma on these techniques.

CONCLUSION

The imaging characterization of adrenal lesions has continued to advance over the past decade as new technologies have evolved. CT, MRI, PET, and PET/CT are now established clinical techniques capable of differentiating benign from malignant adrenal lesions.

Computed tomography findings in diseases of the adrenal gland

The adrenal gland is a common site of disease, with an abnormality prevalence as high as 9% in autopsy series. With the increasing use of CT, adrenal lesions are frequently found in the daily practice of radiology and are diagnosed in up to 5% of CT examinations performed for varied reasons. Imaging features on CT can establish a specific diagnosis of many of these lesions, including myelolipoma, hematoma and cysts. Once a diagnostic dilemma, now adenomas can be accurately diagnosed using unenhanced CT, chemical shift magnetic resonance imaging and CT contrast washout analysis. Because the adrenal gland is also a frequent site of metastasis, recent literature has focused on imaging characterization of adrenal masses for differentiation of adenomas from metastases. In patients without known malignancy, most adrenal lesions are benign and a specific diagnosis can now be made on the basis of imaging features. It is important to understand the prevalence of adrenal abnormalities because the gland is a common site of disorders, and the increased use of cross-sectional imaging has increased the frequency of detection of adrenal lesions. The prevalence of disease is important in predicting the risk of malignancy when an adrenal mass is discovered in a patient without known cancer. Detection of adrenal gland diseases has increased substantially with the advent and widespread use of imaging techniques. Although several imaging modalities can be used, CT has a central role in both detection and differential diagnosis of an adrenal lesion. The aim of this article is to review the CT findings of adrenal gland diseases.