Functioning and nonfunctioning cysts of the adrenal cortex and medulla

A Cyst-ematic Analysis of the Adrenal Gland: A Compilation of Primary Cystic Lesions From Our Institution and Review of the Literature

OBJECTIVES

Although primary adrenal lesions and metastases are most commonly encountered, de novo cysts of the adrenal gland can occasionally occur.

METHODS

We analyzed the pathology archives at the Hospital of the University of Pennsylvania for diagnoses of cystic lesions of the adrenal gland between 1998 and 2020. Patient demographics and clinical information were extracted, and pathology slides and stains, as appropriate, were analyzed. The literature between 1998 and 2020 was also searched for large case series involving cystic adrenal lesions.

RESULTS

We found 18 cystic lesions of the adrenal gland in our archives, categorized as pseudocysts (7), endothelial cysts (5), mesothelial cysts (2), mature teratoma (1), cystic adrenal cortical adenoma (1), cystic pheochromocytoma (1), and cystic metastasis (1). The mean age at time of diagnosis was 52.3 years, and the mean size of the cysts was 6.0 cm. There was a slight female predilection, and cysts were more likely to be found on the left side. All lesions were incidental findings. The cystic metastasis was clear cell renal cell carcinoma. Our findings were also compared with those found in the literature published within the same timeframe.

CONCLUSIONS

Adrenal cysts are rare entities. Our findings are concordant with other large studies and provide additional cases to the existing literature. In addition, our literature search expands the possible differential diagnoses for cystic lesions arising in the adrenal gland.

Cystic lesions of the adrenal gland: our experience over the last 20 years

Cystic lesions of the adrenal gland are uncommon, often presenting with nonspecific clinical and radiologic findings, and are thus underrecognized. They are occasionally associated with malignant neoplasms, which can greatly mimic benign lesions and carry detrimental clinical consequences if misdiagnosed. Here we present our 20-year experience (1992-2012) with these lesions at an academic medical center. Among more than 4500 adrenal gland specimens, 31 cases of adrenal lesions with a predominant cystic component were identified in 30 patients with an age range of 34 to 86 years (median, 55.5 years) and a male/female ratio of 13:17. Macroscopic descriptions, available histologic and immunostain slides, and available radiologic records were reviewed for all included cases. Radiologic studies and gross examination correlated well, and hemorrhage (26 cases; 84%) and encapsulation (25 cases; 81%) appeared to be nonspecific radiologic/gross features shared across histologic subtypes. Microscopic review identified 12 cases (39%) of pseudocysts, 2 cases (6%) of endothelium-derived cysts, and 17 cases (55%) of epithelium-derived cysts. Among these 31 cystic adrenal lesions, 2 cases (6%) were malignant neoplasms (1 epithelioid angiosarcoma, 1 adrenocortical carcinoma). Radiologic impression and histopathologic diagnosis were concordant in 11 (73%) of the 15 cases for which radiologic records were available. This study represents the second largest case series to date on cystic adrenal lesions and presents a comprehensive review on their demographic, clinical, radiologic, and gross and microscopic pathologic features, as well as their differential diagnoses.

Adrenal pseudocyst: a unique case with adrenal renal fusion, mimicking a cystic renal mass

We describe an unusual adrenal pseudocyst mimicking radiologically and clinically renal mass. The cyst measured 12 cm in diameter and had a fibrotic external envelope that was fused with the renal capsule. The possible diagnostic pitfalls encountered in this case are discussed.

Cystic adrenal neoplasms

BACKGROUND

Cystic lesions of the adrenal gland are uncommon and demonstrate a spectrum of histologic changes and may vary from pseudocysts to malignant cystic neoplasms.

METHODS

The authors analyzed a series of primary cystic lesions of the adrenal gland to evaluate the clinicopathologic features and histologic spectrum and to determine features that are helpful in distinguishing benign from malignant cystic adrenal tumors.

RESULTS

A total of 41 cases of macroscopically cystic lesions among patients who underwent surgery at the Mayo Clinic were identified over a 25-year period. Of these 41 cases, 32 were pseudocysts, 8 were endothelial cysts, and 1 was an epithelial cyst. Of the 32 pseudocysts, 6 were associated with adrenal neoplasms, including 2 adrenal cortical carcinomas, 2 adrenal cortical adenomas, and 2 pheochromocytomas. One pheochromocytoma case was identified in association with an endothelial cyst. Both patients with cystic adrenal cortical carcinomas died of disease.

CONCLUSIONS

Adrenal neoplasms, including adrenal cortical carcinomas, may be associated with benign-appearing cysts. Extensive pathologic sampling of resected tissues is important to rule out malignancy in patients with cystic adrenal lesions.

Prenatal diagnosis of an adrenal cyst: a case report

We report a rare case of fetal adrenal cyst, diagnosed prenatally during routine ultrasound screening at 36 weeks' gestation. Serial ultrasonographic evaluations demonstrated a slight increase in the size of the cyst during pregnancy. A healthy female baby, weighing 2,810 g with Apgar scores of 8 and 9 at 1 and 5 minutes, respectively, was delivered vaginally at term. She underwent successful surgery at the age of 10 days. The postoperative course was smooth and the baby is currently doing well. Histology revealed an adrenal cyst.

Isolated visceral leishmaniasis presenting as an adrenal cystic mass

A 69-year-old woman presented with a large left retroperitoneal suprarenal mass. Radical resection of the left kidney and the mass revealed a cystic adrenal tumor with a weight of 1500 g. Histologic examination showed that the cyst was composed mostly of partially organized clotted blood. The periphery of the mass consisted of a thin rim of cortical and medullary adrenal tissue with superimposed granulomatous chronic inflammation. The infectious nature of the process was manifested by the scattered intracellular and extracellular Leishmania amastigotes that were found throughout the lesion. The differential diagnosis of cystic adrenal masses and the unusual presentation of visceral leishmaniasis are discussed in this context.

Comparative analysis of plasma 17-hydroxyprogesterone and cortisol responses to ACTH in patients with various adrenal tumors before and after unilateral adrenalectomy

Patients with non-hyperfunctioning adrenal adenomas often have an increased plasma 17-hydroxyprogesterone response to ACTH stimulation. The effects of adrenal surgery on this abnormality have rarely been investigated. One hundred and sixty-one patients with unilateral adrenal tumors (non-hyperfunctioning adenomas, 78; cortisol-producing adenomas, 8; aldosterone-producing adenomas, 37; adrenal cysts, 12; pheochromocytomas, 26) were studied. Patients before and after adrenal surgery as well as 60 healthy subjects underwent an ACTH stimulation test using 2 mg synthetic ACTH(1-24) (Cortrosyn Depot, Organon). Basal and ACTH-stimulated plasma 17-hydroxyprogesterone and cortisol concentrations are reported. Before adrenal surgery, the basal plasma 17-hydroxyprogesterone concentrations were normal in patients with all types of tumors. However, the ACTH-stimulated plasma 17-hydroxyprogesterone levels were abnormally increased in 53% and 31% of patients with non-hyperfunctioning adenomas and aldosterone-producing adenomas, respectively. In addition, a few patients with adrenal cysts and pheochromocytomas also showed an increased ACTH-stimulated 17-hydroxyprogesterone response. After unilateral adrenalectomy, this hormonal abnormality disappeared in most, although not all patients with adrenal tumors. In patients with non-hyperfunctioning adrenal tumors, ACTH-stimulated plasma 17-hydroxyprogesterone and cortisol concentrations significantly correlated with the size of the tumors. These results firmly indicate that the tumoral mass itself may be responsible for the increased plasma 17-hydroxyprogesterone and cortisol responses after ACTH stimulation in patients with non-hyperfunctioning and hyperfunctioning adrenal adenomas.

Pheochromocytoma in an incidentally discovered asymptomatic cystic adrenal mass

Cystic adrenal lesions can be either cortical or medullary, and distinguishing between these 2 types of lesions may be important in patient management. Pheochromocytomas, which are adrenal medullary neoplasms, typically manifest with hypertension, headaches, palpitations, tachycardia, sweating, and anxiety symptoms; however, 10% to 17% of patients with pheochromocytomas are asymptomatic. We describe a 67-year-old woman with lifelong headaches and recent persistent cough in whom a left cystic adrenal mass was incidentally discovered by computed tomography of the chest. A moderate increase in normetanephrine and total metanephrine values in two 24-hour urine samples suggested a pheochromocytoma. Computed tomography with use of contrast medium revealed ring enhancement of the cyst wall, a finding consistent with an adrenal medullary tumor. This report demonstrates the importance of repeated 24-hour urine samples to determine the metanephrine values together with contrast-enhanced computed tomography in a patient with nonspecific symptoms.

Management of Adrenal Cysts

Adrenal cysts have been traditionally managed by excision to rule out malignancy. We reviewed the 613 cases of adrenal cysts (including 6 new cases of our own) to evaluate whether this is still appropriate. Descriptive statistics and distribution of each pathologic type have been updated, based on 515 cases, and have changed from statistics compiled on 155 cases by G. A. Absehouse et al. Only seven per cent of all adrenal cysts are malignant or potentially malignant. There is only one reported case of a malignancy found in a nonfunctioning adrenal cyst that was initially thought to be benign. In this case, no CT or aspiration was performed. There have been 19 cases of adrenal cysts managed with aspiration. All were nonfunctioning and benign. One had a bloody aspirate. Reaccumulation occurred in 32 per cent of the cases (six cases); six per cent were symptomatic, four per cent were excised. Follow up was available in 15 cases from 4 months to 3.5 years. Management of the patient with a suspected adrenal cyst should include a careful history and physical and biochemical screening to rule out a functioning lesion. A CT scan, and aspiration of the cyst with a cystogram should be performed to confirm a simple cyst of the adrenal. If the suspicion of malignancy is low, and the lesion is nonfunctional, the adrenal cyst may be managed by aspiration alone. If the cyst recurs and is asymptomatic, it may be observed. If a symptomatic cyst recurs, it may be reaspirated or excised.

Adrenal cortical epithelial cysts in two saddleback tamarins (Saguinus fuscicollis)

Adrenal cysts of epithelial origin were found incidentally in the adrenal cortical tissues of two adult female saddleback tamarins. In one case, a small cluster of minor cysts was located at the cortico-medullary border. The cysts were filled with a periodic acid-Schiff (PAS)-positive, amorphous substance and lined by a cuboidal PAS-negative epithelium, which resembled morphologically the ascending Henle's loops of the kidney. These microcysts were thought to be mesonephric remnants. In the second case, two large cysts of 1 to 3 mm diameter extended throughout the entire cortex. The cysts were filled by a watery, PAS-negative fluid and lined by a bi- to multi-layered, cytokeratin-positive epithelium. The basal epithelial layer consisted of cuboidal cells, which became cylindrical to drop-like in appearance towards the cyst lumen. The cysts closely resembled mesothelium-derived adrenal cysts in man. This is the first report of adrenal cysts in non-human primates.

Adrenal cystic lesions: report of 12 surgically treated cases and review of the literature

Adrenal cysts are rare (0,064%-0,18% in autopsy series) and less than 500 cases have been reported in the western literature. Incidental diagnosis of adrenal cysts, however, is reported with increasing rates. We observed 12 patients with adrenal cyst. Each of them had a careful laboratory and instrumental evaluation; all the patients were operated. In our series about 67% of the patients were symptomatic (6 patients with abdominal pain, 1 with palpable mass, 1 with hemorrhagic shock). No biochemical alteration was observed. Conversely we observed an unusual subclinically hyperfunctioning cystic adenoma, potentially progressive to a clinically recognizable endocrine syndrome. US, CT and MRI had a sensitivity of 66,7%, 80% and 100% respectively. Adrenalectomy was performed in all patients. The pathological findings were: 1 epithelial cyst (cystic adenoma), 2 endothelial cysts (vascular cystic ectasia with adenomatous adrenocortical hyperplasia and 1 vascular cyst) and 9 pseudocysts. On the basis of these results, we conclude that a careful hormonal, morpho-functional and instrumental evaluation is indicated in all adrenal cysts, even if the available diagnostic procedures, even when combined, cannot always define their nature. Surgical excision, when possible by laparoscopic approach, is indicated in presence of symptoms, endocrine abnormalities (even when subclinic), complications, suspicion of malignancy and/or large size (>5 cm). Adrenal gland must be excised en bloc, also because of the possible presence of other adrenal lesions.

Adrenal Pseudocysts: Evidence of Their Posthemorrhagic Nature

Hemorrhagic adrenal pseudocysts are uncommon nonneoplastic lesions that have been reported as secondary to intraparenchymal hemorrhage or alternatively related to endothelial (vascular) cysts. Ultrastructural and ammunohistochemical evidence in support of the latter has been presented, but the exact nature of hemorrhagic adrenal pseudocysts remains poorly defined. We evaluated six surgical specimens of hemorrhagic adrenal pseudocysts using immunohistochemical staining for CD31 and CD34, as well as conventional histochemistry. All six cases had hemorrhagic contents within a wall of variable thickness possessing focal areas of linear, disrupted elastin, and smooth muscle. Three cases demonstrated extensive thrombosis with organization, including papillary endothelial hyperplasia, simulating angiosarcoma. In these cases, CD3I and CD34 staining decorated areas of papillary endothelial hyperplasia as well as foci of the internal cyst lining, whereas the other cases were negative for both antibodies. Of interest is the history of FNA prior to surgical resection in three cases of hemorrhagic adrenal pseudocysts, two of which showed papillary endothelial hyperplasia. The presence of papillary endothelial hyperplasia and our immunohistochemical findings support the conclusion that adrenal pseudocysts are posthemorrhagic and derive from vascular disruption. Furthermore, FNA or other interventional studies may be associated with papillary endothelial hyperplasia in hemorrhagic adrenal pseudocysts.

Mesothelial cyst of the adrenal gland

A case of mesothelium-lined cyst of the adrenal gland is reported. Although more than 300 adrenal cysts have been reported in the literature, epithelial cell-lined cysts are rare and comprise only 9% of the cases. An adrenal cyst was found, the lining cells of which had features consistent with mesothelial cells. The inner surface of the cyst was lined by a single layer of cuboidal cells, which showed alcian blue positive cellular outline. Immunohistochemically, the lining cells were positively stained for keratin, epithelial membrane antigen and CA-125. Electron microscopic examination revealed many long complex microvilli and desmosomes in the lining cells. There was a basal lamina beneath the cell layer. These morphological and immunohistochemical findings indicated that the lining cell is derived from mesothelium.

Hemorrhagic pseudocysts of the adrenal gland: Case description

Cysts of the suprarenal gland, classified as parasitical cysts, epithelial cysts, endothelial cysts and pseudocysts are uncommon. We report a case of pseudocysts of the suprarenal gland. Clinical signs consisted of flank pain and palpable mass. Urography, ultrasonography and computed tomography were essential for diagnosis. Treatment consisted of surgical extirpation, as percutaneous needle aspiration entails high rate of recurrences.

Haemorrhagic pseudocyst of the adrenal in an adult (a case report)

An adult female patient presenting with a cystic abdominal mass and intermittent fever, was found at surgery to have a large cyst of the left adrenal gland. The imaging findings and pathology of this uncommon entity are discussed.

Adrenal pseudocyst: a clinical and pathologic study of eight cases

Adrenal pseudocysts are cystic lesions arising within the adrenal gland surrounded by a fibrous tissue wall devoid of a recognizable lining layer. This study comprised eight adrenal pseudocysts surgically excised at the Massachusetts General Hospital. The median age of the patients was 41 years. Seven of the eight individuals were women. There was no apparent etiologic relationship to prior trauma or pregnancy. Half of the patients described symptoms that resolved following pseudocyst removal. The remaining individuals were asymptomatic with adrenal pseudocysts discovered incidentally during the work up of other medical problems. Adrenal pseudocyst size ranged from 1.8 to 10 cm. Pseudocyst size did not correlate with the presence of symptoms. The histologic and immunohistochemical findings in this study suggest that at least some adrenal pseudocysts are of vascular origin. In two lesions, small foci of residual cells lining the inner pseudocyst wall were found that expressed factor VIII antigen (also Ulex Europaeus lectin in one case) but not vimentin, keratin, or epithelial membrane antigen. In both cases, abundant elastic tissue was present in the pseudocyst wall, and in one lesion, adrenal vein smooth muscle was present as well. In both cases, dilated sinusoids were found at the periphery of the pseudocysts and, in one lesion, the sinusoids appeared to coalesce to form the pseudocyst cavity. In the majority of the remaining six cases there was also some histologic evidence to suggest a vascular origin. In five and three cases, respectively, abundant elastic tissue and adrenal vein smooth muscle were found within the pseudocyst wall. In two lesions, both elastic tissue and smooth muscle were present. In addition, adrenal sinusoids were prominently dilated at the periphery of four pseudocysts and, in one case, the sinusoids appeared to coalesce to form the pseudocyst cavity.

Epithelial-lined (true) cyst of the adrenal gland: a case report

A case of an epithelial-lined (true) adrenal cyst is reported. Although over 300 adrenal cysts have been reported in the literature, true cysts are rare. In this case, a 4.0 cm cyst lined by cuboidal to flattened cells with bland cytologic features was incidentally found at autopsy. Immunologic studies performed on formalin-fixed, paraffin-embedded sections demonstrated that the cells expressed keratins (AE1/AE3+, CAM 5.2+, and MAK-6+) and were negative for epithelial membrane antigen, vimentin, factor VIII, and desmin. Normal adrenal cortical and medullary cells did not express keratins, suggesting that the cyst lining was not derived from either adrenal cortex or medulla. A mesothelial origin, with a pathogenesis analogous to the formation of primary cysts of the spleen, is proposed.

Adrenal cysts--report, review and classification

A case of a giant adrenal pseudocyst is reported. The clinico-pathological features are reviewed and a classification is proposed.

Diagnosis and treatment of functioning and nonfunctioning adrenocortical neoplasms including incidentalomas

The most important functional tumors of the adrenal cortex are those that secrete cortisol or aldosterone in excess. Biochemical testing when appropriately utilized can diagnose and differentiate the cause of Cushing's syndrome, and when an adrenal adenoma is found, surgical excision is curative. The diagnosis and surgical treatment of primary aldosteronism are straightforward today, and localization of the usual small cortical tumor producing the syndrome can be achieved by CT and NP-59 scanning or selective venous assays. Adrenocortical carcinomas are relatively rare, are usually incurable when diagnosed, and are an important consideration in the incidentally discovered adrenal mass found by CT scanning.

The incidentally discovered adrenal mass

With the wider application of increasingly sensitive computed tomographic scans, more adrenal masses will be discovered incidentally. Because benign lesions of the adrenal are much commoner than malignant ones, an approach is needed to determine which incidentally discovered masses should be removed. The history and physical examination may guide the evaluation. Imaging studies and needle biopsies have limited value. If the history and physical findings do not suggest a diagnosis, an approach using the size of the mass, results of any cyst puncture, and a biochemical assessment may determine which patients should have surgery. This approach is based on the relative prevalence of benign and malignant clinically silent adrenal tumors.

Pyogenic cyst of adrenal gland

A case of cystic lesion of the adrenal gland is presented. Ultrasonography and computerized tomography greatly facilitate the diagnosis of these lesions. The cause, differential diagnosis, and treatment of adrenal cysts are discussed.

Adrenal cysts: pathogenesis and histological identification with a report of 6 cases

Because of their rarity cysts of the adrenal gland are often misinterpreted and misdiagnosed. Six cases of surgically removed adrenal cysts are presented, including 3 endothelial cysts, 2 epithelial retention cysts and 1 pseudocyst. Evidence is presented that epithelial retention cysts could and do develop in the human adrenal cortex and are not theoretically impossible as propagated in the literature. We also emphasize the importance of evaluating the surrounding fibrous and adrenal tissue in the proper identification of these cysts, a point not sufficiently stressed previously.