Two Cases of Adrenal Cysts Lined by Thyroid Follicular Epithelium: Addressing Cellular Origin and Malignancy Concerns

Adrenal cysts lined by thyroid follicular epithelium are rare, with only 14 reported cases of "ectopic thyroid tissue" to date. While the primary consideration for differential diagnosis is thyroid carcinoma metastasis, exclusion of metastases is determined based on the absence of a primary thyroid lesion, serological euthyroidism, lack of thyroglobulin elevation, and absence of epithelial atypia. Herein, we report 2 cases of adrenal cysts lined by thyroid follicular epithelium. Case 1 was a 60-year-old woman with a right adrenal cyst. Case 2 was a 51-year-old man with a left adrenal cyst. Over time, both cysts became larger, necessitating an adrenalectomy. Cystic epithelia were lined with thyroid follicular epithelium, exhibiting moderate atypia. Human bone marrow endothelial cell marker-1 and galectin-3 were focally positive; CK19 was positive in Case 1, and all 3 markers were positive in Case 2, previously reported as an immunophenotype of thyroid carcinoma. CD56 expression was positive in both cases. Targeted next-generation sequencing revealed several low-frequency mutations; however, no major driver alterations for thyroid cancer were detected. Adrenal cysts can be lined by thyroid follicular epithelium. Challenges arise in determining the malignant or benign nature of adrenal cysts.

Adrenal Cysts: To Operate or Not to Operate?

Adrenal cysts are uncommon and usually asymptomatic, and therefore are usually incidentally discovered adrenal lesions. They have a broad pathohistological spectrum that includes pseudocysts and endothelial (vascular), parasitic, and epithelial (mesothelial) cysts. Although most adrenal cysts are benign and hormonally non-functional lesions, some can have ambiguous imaging appearances and mimic malignant adrenal neoplasms. On the other hand, the actual malignant neoplasms could undergo cystic transformation. Additionally, immune cell infiltrations, thrombosis, or haemorrhage seen in sepsis can frequently cause adrenal cyst development, raising a question about the possible connection between severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) and adrenal cystic lesions. Due to the disease's rarity, the likelihood of malignancy, and the lack of specific guidelines, the management of adrenal cysts is always challenging especially in a young person. This review discusses the important diagnostic and the current treatment possibilities for adrenal cystic lesions. Aiming to emphasize clinical dilemmas and help clinicians navigate the challenges when encountering a patient with an adrenal cyst in everyday practice, we based our review on a practical question-answer framework centred around the case of a young woman with an incidentally discovered large adrenal cyst.

Curious Case of a Giant Retroperitoneal Cyst

Adrenal cysts are uncommon fluid-filled masses that develop in the adrenal gland. Typically, they are non-functional, asymptomatic, and smaller than 10 cm in diameter when incidentally detected. However, the presence of giant adrenal cysts, exceeding 10 cm in diameter, creates a diagnostic challenge due to the difficulty in determining their origin. Surgical intervention is advised when the cyst surpasses 10 cm in diameter, produces symptoms, causes endocrine abnormalities, exhibits intracystic bleeding, or raises suspicion of malignancy. The preferred treatment approach involves adrenalectomy, performed either through open surgery or laparoscopy. In cases where the diagnosis is unequivocal, ultrasound-guided percutaneous drainage serves as an alternative. Here, we present an exceptional case of a massive retroperitoneal mass caused by a rare giant adrenal cyst.

Rare benign adrenal lesions

While most benign lesions of the adrenal glands represent either an adrenocortical adenoma or a myelolipoma, the advent and frequent use of high-resolution radiological investigations have led to relatively increased incidental discovery of rare adrenal lesions, specifically benign adrenal cysts, adrenal ganglioneuromas, adrenal schwannomas, adrenal hemorrhage, and adrenal calcifications. Radiological characteristics of the different rare benign adrenal lesions could vary from distinct to indeterminate. Though typically nonfunctional, these rare lesions require evaluation for adrenal hormone excess, as they may phenotypically appear similar to pheochromocytoma or adrenocortical carcinoma and could sometimes be associated with or conceal an underlying functional adrenal tumor. In this review, we discuss the various rare benign adrenal lesions, emphasizing a practical perspective.

Cystic adrenal lesions: A report of five cases

Background

Cystic adrenal lesions are rare and uncommon manifestation with few cases reported so far. Different types of adrenal cysts have been described with heterogeneous etiology and overlapping clinical findings, ranging from benign to malignant cystic neoplasm. They are usually asymptomatic or may rarely present with abdominal pain or fullness. Optimum management of adrenal cysts still remain controversial, owing to its low incidence. In this study, we report our institutional experience on diagnosis and management of different histological types of cystic adrenal lesions.

Cases

During 4 years period, 55 patients underwent adrenalectomy with five cases presenting as adrenal cysts. All the five patients were biochemically nonfunctional and underwent adrenalectomy (laparoscopic anterior n = 2, retroperitoneoscopic approach n = 1, and open anterior transperitoneal approach n = 2). The primary indications for surgery were larger size and/or suspicion of malignancy. Histological evaluation revealed two epithelial cysts, one endothelial cyst, one pseudocyst, and a very rare case of adrenocortical carcinoma arising in a pseudocyst.

Conclusion

Cystic adrenal lesions are rare with varied etiologic and clinical presentation that may sometimes lead to diagnostic and management dilemma. These cases must undergo biochemical and radiological evaluation to rule out underlying malignancy followed by referral for surgical intervention.

A histopathological study on adrenal cysts in ferrets

Adrenal disorders are common in ferrets, but there are few studies on cystic lesions of the adrenal gland. The present study describes pathological and immunohistochemical features of adrenal cysts in eleven ferrets and discusses their histogenesis. In nine of eleven cases examined, which included seven, one, and one right, left, and bilateral cases, respectively, cysts were in the adrenal cortex and lined with epithelial cells. These epithelial cells contained an Alcian blue-negative/PAS-positive material and were positive for cytokeratin (CK) 7. The staining pattern was similar to that of biliary epithelial cells in the ferret. In five of the cases, there were small ducts adjacent to the cysts that were positive for CK7 and CK20 and negative for CK19. Based on the anatomical proximity between the right adrenal and liver, the immunohistochemical features of the small duct cells were comparable to those of hepatic oval cells. These results indicate the possibility that these adrenocortical cysts in the ferret originated from the biliary system. In the other two cases, the cysts lacked an epithelial cell lining, and there were dilated lymphoid vessels around the cysts. These cysts were assumed to have developed in the adrenal medulla, because the cyst wall was positive for glial fibrillary acidic protein and there were adrenal medullary cells positive for synaptophysin in the cyst wall. Therefore, the medullary cysts may have been associated with dilated vasculatures.

Cystic adrenal lesions: focus on pediatric population (a review)

BACKGROUND AND AIM

The cysts may potentially affect any organ; adrenals cysts are rare. This is a review of the literature regarding adrenal cysts, focusing on children and young adults.

GENERAL DATA

Three major types have been described: pure cysts (endothelial, epithelial, and hemorrhagic or pseudocyst), parasitic (as hydatid) cysts and cystic part of a tumour (most frequent are neuroblastoma, ganglioneuroma, pheocromocytoma, and teratoma). The complications are: bleeding, local pressure effects; infection; rupture (including post-traumatic); arterial hypertension due to renal vessels compression. Adrenal hemorrhage represents a particular condition associating precipitating factors such as: coagulation defects as Factor IX or X deficiency, von Willebrand disease, thrombocytopenia; antiphospholipid syndrome; previous therapy with clopidogrel or corticosteroids; the rupture of a prior tumour. At birth, the most suggestive features are abdominal palpable mass, anemia, and persistent jaundice. Adrenal insufficiency may be found especially in premature delivery. The hemorrhage is mostly self-limiting. Antenatal ultrasound diagnosis of a cyst does not always predict the exact pathology result. The most important differential diagnosis of adrenal hemorrhage/hemorrhagic cyst is cystic neuroblastoma which is highly suggestive in the presence of distant metastases and abnormal catecholamine profile. The major clue to differentiate the two conditions is the fact that the tumor is stable or increases over time while the adrenal hemorrhage is expected to remit within one to two weeks.

CONCLUSION

Pediatric adrenal cysts vary from simple cysts with a benign behavior to neoplasia- related lesions displaying severe prognosis as seen in cystic neuroblastoma. A multidisciplinary team is required for their management which is conservative as close follow-up or it makes necessary different surgical procedures in cases with large masses or if a malignancy suspicion is presented. Recently, laparoscopic approach is regarded as a safe procedure by some authors but generally, open surgery is more frequent used compare to adults; in most cases the preservation of normal gland is advisable.

Laparoscopic treatment of adrenal cysts--own research and literature review

MATERIAL AND METHODS

Over the last 18 months we operated on six patients with large adrenal gland cysts in our centre. This consisted of 8.2% of all patients treated in said period due to adrenal gland pathologies. On ruling out malignancy or parasitic nature of the lesions, all patients were surgically treated in order to excise the cysts while leaving the gland untouched. In five patients the cysts were resected but the adrenal gland was spared. However, in one patient the adrenal gland coated the entire cystic mass, which imposed performance of adrenalectomy in addition to cystectomy. During surgeries we tried not to clip the suprarenal vein, which we managed to do in four out of six cases.

RESULTS

A one-year remote follow-up period revealed no cyst recurrence in ultrasound or CT, and it was possible to visualise the remaining part of the adrenal gland in all cases.

CONCLUSION

Thus, in our opinion resection of benign cysts is well justified and recommendable.

Cystic lymphangioma of adrenal gland: a clinicopathological study of 3 cases and review of literature

Cystic lymphangioma of the adrenal gland is a rare and benign lesion, most often found incidentally during abdominal imaging studies, abdominal surgery or at autopsy. We aimed to retrospectively review all adrenal lymphangioma cases at our hospital, further document their lymphatic origin by immunohistochemical staining and discuss the differential diagnosis with other cystic adrenal gland lesions. A total of 3 adrenal lymphangioma cases were identified. All three patients were men and adults at time of diagnosis aged 41 years, 43 years, and 66 years, respectively. All were incidentally identified during investigating for unrelated reasons, two of which were discovered by routine radiologic check-up while the last one was found during imaging detection of ureteral cancer. The average size of an adrenal lymphangioma lesion was 3.2 cm (range, 2.5-4.6 cm). Histologically, all three cases showed a typical multicystic architecture with dilated spaces lined by flattened, bland, simple lining. The cystic spaces occasionally contained proteinaceous material but lacked red blood cell content. On immunohistochemical stains, D2-40 cytoplasmic staining was positive in all three lesions, whereas AE1/AE3 was negative, thus, confirming their lymphatic nature.

Cystic lymphangioma-like adenomatoid tumor of the adrenal gland: report of a rare case and review of the literature

Adenomatoid tumors (AT) are uncommon, benign tumors of mesothelial origination most frequently encountered in the genital tracts of both sexes. Their occurrences in the extragenital sites are much rarer and could elicit a variety of differential diagnosis both clinically and morphologically. With regard to the adrenal gland, to the best knowledge of us, only 31 cases of AT have been reported in the English literature. Several histologic growth patterns have been documented in AT, among which cystic type is the least common one. We herein present a further case of AT arising in the adrenal of a 62-year-old Chinese man with a medical history for systemic hypertensive disease. The tumor was incidentally identified during routine medical examination. An abdomen computed tomography scan revealed a solitary mass in the right adrenal. Grossly, the poorly-circumscribed mass measured 3.0 x 3.0 x 2.0 cm with a cut surface showing a gelatinous texture with numerous tiny cystic structures. Microscopic examination showed an infiltrated lesion with honeycomb appearance mimicking a lymphangioma, which composed predominantly of variably sized and shaped anastomosing small cystic spaces lined by flattened endothelial-like cells, without any epithelioid or signet-ring like components present. Foci of extraadrenal tumor extension, lymphoid aggregates with occasional germinal centre formation, intralesional fat tissue, stromal myoid proliferation and ossification were also observed. Immunohistochemical analyses confirmed the mesothelial differentiation of this tumor and indicated a diagnosis of cystic lymphangiomatoid AT of the adrenal.

Spontaneous rupture and hemorrhage of adrenal pseudocyst presenting with acute abdomen and shock

Adrenal gland pseudocysts are not common conditions, and most of them are nonfunctional and asymptomatic. However, large pseudocysts may causes abdominal discomfort and have compressive effects on adjacent organs. They may rupture spontaneously or after trauma, and lead to retroperitoneal hemorrhage and surgical emergency. Herein, we report a case of 21-year-old female who presented with acute abdomen and hemorrhagic shock due to spontaneous rupture of adrenal pseudocyst. She was treated successfully by open surgery, removal of adrenal pseudocyst and unilateral adrenalectomy.