The Natural History and Treatment of Adrenal Myelolipoma

Management of patients with adrenal myelolipoma: experience from a tertiary referral centre

BACKGROUND

Adrenal myelolipomas are rare, benign, tumours of the adrenal cortex.

AIMS

This study reports the experience of a tertiary adrenal surgery referral centre's approach to the management of patients with adrenal myelolipoma.

METHODS

A retrospective observational cohort study was conducted on all adult patients (> 18 years age) diagnosed with adrenal myelolipoma from January 1, 2014, to December 30, 2022. Demographics, imaging characteristics, histological diagnosis (where applicable) and follow-up data were compared between patients undergoing surgery and those referred to surveillance. Indications for operative intervention were recorded at the time of multidisciplinary team discussion, consisting of surgeons, endocrinology physicians, radiologists, pathologists and specialist nursing representatives.

RESULTS

Of the 522 patients with an adrenal lesion discussed in adrenal tumour meeting between 2014 and 2022, n = 15 (2.8%) were diagnosed with adrenal myelolipoma. Of the 15 patients, 4 underwent adrenalectomy at first presentation (27%), while 1 patient underwent adrenalectomy after interval follow-up. Indications for operative intervention were as follows: 'indeterminate lesion' (n = 3), 'abdominal pain and size (> 4 cm)' (n = 1) and 'mass effect on adjacent organs' (n = 1). The mean rate of lesion growth in patients referred for surveillance (n = 10) was 0.13 cm/year. Histology confirmed adrenal myelolipoma as the diagnosis in all resected tumours.

CONCLUSIONS

For patients with adrenal myelolipoma, the presence of symptoms and/or indeterminate features on imaging may be more clinically useful indications for operative intervention over size alone. The surveillance of adrenal myelolipomas, even in patients with adrenal lesions > 4 cm, is a safe clinical strategy, provided the imaging characteristics are benign and patients remain asymptomatic.

Three-dimensional CT cinematic rendering of adrenal masses: Role in tumor analysis and management

The adrenal gland is home to an array of complex physiological and neoplastic disease processes. While dedicated adrenal computed tomography (CT) is the gold standard imaging modality for adrenal lesions, there exists significant overlap among imaging features of adrenal pathology. This can often make radiological diagnosis and subsequent determination of the optimal surgical approach challenging. Cinematic rendering (CR) is a novel CT post-processing technique that utilizes advanced light modeling to generate highly photorealistic anatomic visualization. This generates unique prospects in the evaluation of adrenal masses. As one of the first large tertiary care centers to incorporate CR into routine diagnostic workup, our preliminary experience with using CR has been positive, and we have found CR to be a valuable adjunct during surgical planning. Herein, we highlight the unique utility of CR techniques in the workup of adrenal lesions and provide commentary on the opportunities and obstacles associated with the application of this novel display method in this setting.

A case of adrenal myelolipoma complicated with Prader-Willi syndrome

Introduction

Prader-Willi syndrome is a congenital disorder that occurs in one in 10 000-30 000 children and is characterized by obesity, short stature, and intellectual disability.

Case presentation

A 24-year-old male patient with Prader-Willi syndrome presented with an enlarged adrenal tumor. Computed tomography detected a well-defined mass. Magnetic resonance imaging revealed an increased signal intensity predominantly in fatty areas, suggesting adrenal myelolipoma. Laparoscopic left adrenalectomy was performed. Postoperatively, the patient developed mild pulmonary atelectasis, myelolipoma was confirmed by histopathology, and there was no recurrence at approximately 2 years postoperatively.

Conclusion

This is the first report of Prader-Willi syndrome complicated with adrenal myelolipoma, which was removed laparoscopically.

Imaging incidental adrenal lesions

Incidental adrenal masses are among the most common incidental lesions detected on cross-sectional imaging. The majority are benign lesions, adenomas and myelolipomas being the most common. Simple cross-sectional imaging techniques using CT and MRI permit the characterization of over 80%, thereby requiring no further imaging. The remaining lesions are considered indeterminate. These lesions consist of benign and malignant lesions sharing imaging features. Further imaging and management of these indeterminate lesions should be guided by close collaboration between different specialists in an MDT setting. Advanced imaging options include dedicated adrenal scintigraphy, positron emission tomography CT, biopsy and surveillance. Biochemical and hormonal evaluation is also important to identify hyperfunctioning adrenal lesions. This review focuses on imaging features of benign and malignant adrenal masses used for characterization and suggests an imaging pathway for indeterminate adrenal masses.

Meta-analysis of reported presacral myelolipomas, including a report of a new case

BACKGROUND

Presacral myelolipomas form a rare disease and are often found incidentally in imaging diagnostics.

CASE PRESENTATION

In this study, we report the case of a 71-year-old caucasian female with an incidental finding of a retroperitoneal tumor on magnetic resonance imaging scan. This report aimed at presenting the clinical course of this patient with emphasis on analysis of pathological, clinical, and epidemiological features in a meta-analysis of reported cases.

CONCLUSION

Presacral myelolipomas are rare and its etiology remains unclear. Surgical resection is indicated in symptomatic lesions and lesions > 4 cm. More clinical and pathological research on this rare entity is warranted.

Adrenal Myelolipoma Masquerading as an Adrenal Malignancy

An adrenal myelolipoma presenting with suspicious features may pose a diagnostic challenge to surgeons and endocrinologists. In this case report of an adult patient with undiagnosed congenital adrenal hyperplasia presenting with bilateral adrenal masses, we review his radiographic and clinical findings which were highly suspicious for adrenal malignancy. Features of adrenal myelolipoma that may resemble malignant lesions are reviewed. This case report highlights important features of adrenal myelolipoma that the surgeon and endocrinologist should be aware of. The importance of avoiding overtreating adrenal myelolipomas presenting as tumors of uncertain malignant potential is crucial.

Adrenal myelolipomas

Adrenal myelolipomas are benign, lipomatous tumours with elements of myeloid cells, most of which present as adrenal incidentalomas and comprise 3·3-6·5% of all adrenal masses. Adrenal myelolipomas are usually unilateral (in 95% of cases), variable in size, most often found during midlife, and affect both sexes almost equally. On imaging, adrenal myelolipomas show pathognomonic imaging features consistent with the presence of macroscopic fat. Large adrenal myelolipomas can cause symptoms of mass effect, and can occasionally be complicated by haemorrhage. In the event of a concomitant adrenal cortical adenoma or hyperplasia, adrenal hormone excess might be detected in patients with adrenal myelolipoma. Patients with congenital adrenal hyperplasia exhibit a higher prevalence of adrenal myelolipomas than other patient groups, and are at risk of developing large and bilateral lesions. This Review discusses the pathogenesis, clinical presentation, and management of adrenal myelolipomas.

Adrenocortical adenoma with myelolipomatous metaplasia: a potential diagnostic pitfall: a case report and review of the literature

Background

Adrenal incidentalomas are often found during investigation for another tumor or unrelated problems. Except for adrenal myelolipoma (second most common primary adrenal incidentaloma following adrenocortical adenomas), adrenal lipomatous tumors are uncommon generally and are often described as case reports in the literature. Since the amount of fat is variable, without the help of advanced imaging techniques, some adrenal lipomatous tumors may be misdiagnosed before pathologic examination. Herein, we report a case of adrenal adenoma with myelolipomatous metaplasia that was excised as a periceliac mass in the setting of recurrent pancreatic cyst.

Case report

A 45-year-old Iranian woman with hypertension and end-stage renal disease presented with recurrence of a pancreatic cyst (previous pathologic report was mucinous cyst adenoma). During exploratory laparotomy, the mentioned pancreatic cyst was tightly attached to the stomach and jejunum. There was also a periceliac round rubbery lesion (firstly diagnosed by endoscopic ultrasound) that was excised for ruling out malignancy. Histologic examination of the periceliac mass was found to be adrenocortical adenoma with foci of myelolipomatous metaplasia. The pancreatic cyst histology was just a pseudocyst.

Conclusion

Our case highlights the significance of complete evaluation of incidental findings before surgical intervention, even in the setting of another primary tumor. Myelolipoma and myelolipomatous change (metaplasia) are two different entities. Although very similar as to pathogenesis, there are still some differences.

Presacral myelolipoma, case report and literature review

INTRODUCTION

Myelolipomas are very rare benign tumours consisting of hematopoietic cells and mature adipose tissues. They are most commonly found in the adrenal glands. However, there have been several reported cases of extra-adrenal myelolipomas, most commonly in the presacral region. Nearly all presacral lesions are small and asymptomatic; thus, most are discovered incidentally on imaging studies.

PRESENTATION OF CASE

We report two cases of presacral myelolipomas. The first is a 48-year-old female presenting with atypical back pain, found to have a mass in her presacral region with a size of 3,3 cm. The second case is a 59-year-old female, who presented for evaluation of a hip fracture, found to have a 4,7 cm presacral lesion. Both presacral myelolipomas were discovered incidentally and were confirmed by percutaneous guided fine-needle aspiration biopsy. Both were treated conservatively.

DISCUSSION

Accepted indications for the surgical excision of myelolipomas are symptomatic tumour, size >4 cm, metabolically active tumour, and a suspicion of malignancy on an imaging study. However, previous reports have documented that nearly half of the conservatively managed myelolipomas with a mean initial size of 5,1 cm, has increased in size or became symptomatic over a 3-years period.

CONCLUSION

We conclude that symptomatic presacral myelolipomas or lesions larger than 4 cm should be en-bloc resected, and we present an intuitive decision-making algorithm.

Symptomatic Extra-Adrenal Myelolipoma in the Spleen

A 42-year-old male patient presented with intermittent abdominal pain and gastrointestinal discomfort present for 4 years. Work-up included ultrasound and computed tomography, which identified a fat-containing splenic mass 5.6 cm in size. Due to recurrent symptoms, the patient sought medical care again. Subsequent images showed an increase in size to 7.6 cm, which was concerning for neoplasm. This was removed via open splenectomy, which was challenging due to intra-abdominal adhesions despite never having had any abdominal surgery. The patient's recovery was uncomplicated. Pathologic assessment indicated that the mass was a myelolipoma. Extra-adrenal myelolipomas are rare and typically found within the retroperitoneum but are extremely rare within the spleen. This case report adds the 6^th such case to the literature and demonstrates the need for it to remain in the differential diagnosis of patients with fatty splenic masses, as well as that splenectomy is an appropriate treatment.

Clinical course of adrenal myelolipoma: A long-term longitudinal follow-up study

OBJECTIVE

We aimed to describe clinical course of myelolipoma and to identify predictors of tumour growth and need for surgery.

DESIGN

A retrospective study.

PATIENTS

Consecutive patients with myelolipoma.

RESULTS

A total of 321 myelolipomas (median size, 2.3 cm) were diagnosed in 305 patients at median age of 63 years (range, 25-87). Median follow-up was 54 months. Most myelolipomas were incidentally detected (86%), whereas 9% were discovered during cancer staging and 5% during workup of mass effect symptoms. Thirty-seven (12%) patients underwent adrenalectomy. Compared to myelolipomas <6 cm, tumours ≥6 cm were more likely to be bilateral (21% vs 3%, P < .0001), cause mass effect symptoms (32% vs 0%, P < .0001), have haemorrhagic changes (14% vs 1%, P < .0001) and undergo adrenalectomy (52% vs 5%, P < .0001). Among patients with ≥6 months of imaging follow-up, median size change was 0 mm (-10, 115) and median growth rate was 0 mm/y (-6, 14). Compared to <1 cm growth, ≥1 cm growth correlated with larger initial size (3.6 vs 2.3 cm, P = .02), haemorrhagic changes (12% vs 2%, P = .007) and adrenalectomy (35% vs 8%, P < .0001).

CONCLUSIONS

Most myelolipomas are incidentally discovered on cross-sectional imaging. Myelolipomas ≥6 are more likely to cause mass effect symptoms, have haemorrhagic changes and undergo resection. Tumour growth ≥1 cm is associated with larger myelolipoma and haemorrhagic changes. Adrenalectomy should be considered in symptomatic patients with large tumours and when there is evidence of haemorrhage or tumour growth.

Spontaneous hemorrhage of an adrenal myelolipoma treated with transarterial embolization: A case report

Adrenal myelolipoma is a benign tumor of the adrenal cortex composed predominantly of fat and hematopoietic tissue. These lesions are usually asymptomatic, and most often incidentally detected on imaging. Uncommonly, they present with retroperitoneal hemorrhage, and these have been traditionally treated with emergent surgery. Although, transarterial embolization has been effectively and safely used in patients presenting with active hemorrhage from acute traumatic and nontraumatic causes, literature specifically pertaining to adrenal artery embolization is scant, perhaps due to smaller size and variability of adrenal arteries. With recent advances in endovascular techniques and imaging, there are emerging case reports and series of adrenal artery embolization in acute and nonacute settings. We report a case of spontaneous hemorrhage within an adrenal myelolipoma in a 43-year-old male patient, successfully treated with transarterial embolization, thereby avoiding major surgery. Our report adds to the growing body of literature pertaining to adrenal artery embolization.

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.

Development of multiple adrenal myelolipomas after trauma-induced adrenal haemorrhage

Adrenal myelolipomas represent a benign neoplasm with known associations with many chronic diseases, 21-hydroxylase deficiency and cancer. However, the aetiology of adrenal myelolipomas remains unknown. Here, we present a case of a patient with image-proven bilateral adrenal haemorrhages caused by trauma with the subsequent development of bilateral adrenal myelolipomas several years later. Resection and pathological analysis of left adrenal gland confirmed the presence of multiple adrenal myelolipomas. Our case strongly suggests that trauma was the inciting event that led to the formation of these lesions.

Bilateral adrenal abnormalities: imaging review of different entities

Bilateral adrenal abnormalities are not infrequently encountered during routine daily radiology practice. The differential diagnoses of bilateral adrenal abnormalities include neoplastic and non-neoplastic entities. The bilateral adrenal tumors include metastasis, lymphoma, neuroblastoma, pheochromocytoma, adenoma, and myelolipoma. Non-neoplastic bilateral adrenal masses include infectious processes and haematomas. There are different diffuse bilateral adrenal changes such as adrenal atrophy, adrenal enlargement, adrenal calcifications, and altered adrenal enhancement. In this pictorial review article, we will discuss the imaging features of these entities with emphasis on their clinical implications.

Coexistence of Myelolipoma and Primary Bilateral Macronodular Adrenal Hyperplasia With GIP-Dependent Cushing's Syndrome

Introduction: Adrenal myelolipomas are usually isolated benign adrenal lesions, but can be adjacent to steroid-secreting adrenocortical tumors. We studied the aberrant regulation of cortisol secretion in a 61 year-old woman with combined bilateral myelolipomas and primary bilateral macronodular adrenal hyperplasia (BMAH) causing Cushing's syndrome. Materials and Methods: Cortisol response was measured during in vivo tests that transiently modulated the levels of ligands for potential aberrant receptors, including GIP. Response to medical therapies decreasing GIP was monitored. Expression of ACTH and of GIP receptors were examined in resected adrenal tissues by immunohistochemistry and reverse transcription polymerase chain reaction (RT-PCR). Results: In vivo, cortisol increased in response to mixed meals (+353%), oral 75 g glucose (+71%), GIP infusion (+416%), and hLH IV (+243%). Suppression of GIP by pasireotide improved cortisol secretion but produced hyperglycemia. The left adrenal was predominantly composed of myelolipoma and strands of BMAH, while the right was mainly composed of BMAH with some foci of myelolipoma on pathology. No ACTH was detectable by immunohistochemistry in BMAH or myelolipomas tissue. Ectopic GIP receptor was confirmed by RT-PCR and immunohistochemistry in BMAH tissues but not in the myelolipomas. No germline mutations were identified in the ARMC5 gene of the patient's leucocyte DNA. Conclusion: This is the first report of interspersed myelolipoma and BMAH with GIP-dependent Cushing's syndrome. In contrast with the BMAH tissues, myelolipoma tissue did not express specific GIP receptors. The potential mechanisms responsible for the interspersed growth of those two lesions remain to be identified.

Adrenal Myelolipomas Involved by Plasma Cell Myeloma

OBJECTIVES

To report the presence and evaluate the frequency of plasma cell neoplasms within adrenal myelolipomas.

METHODS

Adrenal myelolipomas within our institution were reviewed for the presence of hematologic neoplasia, and a review of the literature was performed.

RESULTS

Two (9%) of 23 adrenal myelolipomas were involved by plasma cell myeloma. The patients were 71 and 81 years old, one woman and one man, with tumors measuring 7 cm and 8.5 cm, respectively. Both tumors contained large aggregates of dysplastic plasma cells occupying at least one ×10 field and demonstrated light chain restriction. Neither had an established diagnosis of plasma cell neoplasm previously. After receiving therapy, one patient exhibited a stable clinical course 1 year after diagnosis while the other died of disease 3 years later.

CONCLUSIONS

We report the first two cases of adrenal myelolipoma involved by plasma cell myeloma, a rare and subtle finding that has significant clinical implications.

Adrenal myelolipoma: a comprehensive review

INTRODUCTION

Adrenal myelolipoma is an invariably benign neoplasm of the adrenal gland that is the second most common primary adrenal incidentaloma following adrenocortical adenomas. It is composed of elements of adipose tissue and extramedullary hematopoiesis. Hypotheses on stem cells and hormonal factors have been formulated regarding its pathogenesis that is still obscure. Despite its benign behavior, adrenal myelolipoma is clinically relevant as it might cause significant difficulties in the differential diagnosis of adrenal tumors.

METHODS

We have reviewed 420 cases reported between 1957 and 2017 on adrenal myelolipoma retrieved from PubMed and Scopus databases and also 20 of our case series to provide a comprehensive analysis of their pathology, epidemiological and clinical features.

RESULTS AND CONCLUSIONS

The average age for its diagnosis was 51 years, and no gender difference was observed. The average size of tumors was 10.2 cm. Congenital adrenal hyperplasia was associated to 10% of all cases analyzed, while other adrenal hypersecretory disorders (cortisol, aldosterone) were found in 7.5% of cases. Computed tomography and magnetic resonance imaging can be reliably used for its differential diagnosis. If the diagnosis of an adrenal myelolipoma is unambiguous, and no associated symptoms or hormonal activity are established, surgical intervention is usually not necessary.

Case report of a bilateral adrenal myelolipoma associated with Cushing disease

RATIONALE

Adrenal myelolipomas are rare benign tumors, composed of a variable mixture of mature adipose tissue and hematopoietic tissue. These tumors are frequently detected incidentally and are usually asymptomatic, and hormonally inactive.

PATIENT CONCERNS

During a routine health checkup, a 52-year-old man was found to have a tumor on the bilateral adrenal glands. Abdominal computed tomography revealed a well-defined, heterogeneously enhanced bilateral adrenal mass, suggesting a myelolipoma.

DIAGNOSES

The hormonal evaluation revealed adrenocorticotropic hormone (ACTH) dependent Cushing syndrome.

INTERVENTIONS

The patient underwent left adrenalectomy, and transsphenoidal resection of a pituitary mass. The final diagnosis was adrenal myelolipoma associated with Cushing disease.

OUTCOMES

Growth of right adrenal myelolipoma was detected during the 7-year follow-up. There were enhancing pituitary lesions in repeat magnetic resonance imaging of the sellar region, which implies persistent or recurrent pituitary adenoma. This case reinforces relationship between Cushing disease and adrenal myelolipoma.

LESSONS

To the best of our knowledge, this is the first reported pathologically confirmed bilateral adrenal myelolipoma associated with Cushing disease. This report supports the idea that ACTH is associated with the development of adrenal myelolipoma.

The radiographically diagnosed adrenal myelolipoma: what do we really know?

PURPOSE

Adrenal myelolipomas are uncommon, benign tumors of the adrenal glands that are not routinely evaluated for autonomous hormone secretion or followed by repeat imaging, but may lead to retroperitoneal hemorrhage. Little is known about the natural history these tumors with the majority of previous publications being confined to case reports and small case series.

METHODS

We reviewed the computed tomography (CT) reports of 62,279 patients evaluated at a tertiary referral center between 2002 and 2015 for the presence of an adrenal myelolipoma >1 cm in size. We then reviewed the CT imaging and patient charts to determine tumor size, growth, evidence of retroperitoneal hemorrhage, and endocrine dysfunction.

RESULTS

We identified 150 (0.24%) patients with 155 radiographically diagnosed adrenal myelolipomas found on a CT scan during our study period. The median tumor size at discovery was 2.1 cm. Twelve (7.7%) tumors were >6 cm. Sixty-nine (46%) patients had a follow-up CT with a mean time interval between scans of 3.9 years. Eleven tumors (16%) grew over our follow-up period with a median growth rate of 0.16 cm/year. No patient developed a retroperitoneal hemorrhage. Twenty (13%) patients underwent an evaluation for endocrine dysfunction. Three patients had evidence of hypercortisolism and one patient had primary aldosteronism.

CONCLUSION

The majority of radiographically diagnosed adrenal myelolipomas found on abdominal CT imaging are small and slow growing. Retroperitoneal hemorrhage is uncommon, but the rate of associated endocrine dysfunction may be underestimated.

A rare combination consisting of aldosterone-producing adenoma and adrenal myelolipoma in a patient with heterozygosity for retinoblastoma (RB) gene

Various pathological disorders have been associated with primary aldosteronism, including glucagonoma, phaeochromocytoma and primary hyperparathyroidism.

In this report, a case of adrenal myelolipoma (a rare non-functioning tumour composed of mature adipose tissue and normal haematopoietic elements similar to bone marrow cells), aldosterone-producing adenoma and a pituitary microadenoma coexisting in a 62-year-old man with a 15-year history of arterial hypertension, previous ablation of an autonomously-functioning thyroid adenoma, multiple lipomas and an heterozygosity of the retinoblastoma (RB) susceptibility gene is reported.

We believe that this case probably represents another variant of the multiple neoplasia syndrome and we speculate that structural alteration of the RB gene may play a role in the tumorogenesis.

Mediastinal myelolipoma showing gradual enlargement over 9 years: a case report

Background

Myelolipoma is a rare benign tumor composed of mature adipose tissue and normal hematopoietic tissue. Although surgical resection has been recommended due to the potential of progressive enlargement, the natural history of mediastinal myelolipoma has not yet been described. Herein we report a surgically resected mediastinal myelolipoma showing gradual enlargement over a period of 9 years.

Case presentation

A 70-year-old woman presented with a posterior mediastinal mass shadow detected by computed tomography (CT) examination. She had a medical history of sigmoidectomy for colon cancer 13 years previously. A CT scan showed a smooth, well-demarcated 2.8 × 2.1-cm paravertebral mass shadow, composed of a fat density area and a soft tissue density area, which showed gradual enlargement from a 1.6 × 1.0-cm nodule 9 years previously. This was not accompanied by chronic anemia or hematologic disease including thalassemia, and no abnormal accumulation was observed on bone marrow scintigraphy or fluoro-2-deoxyglucose positron emission tomography. With a clinical diagnosis of mediastinal myelolipoma, surgical resection was performed, and pathological examination confirmed the diagnosis.

Conclusions

We experienced a rare case with mediastinal myelolipoma showing gradual enlargement, with a tumor doubling time of 1,212 days.

The management of bilateral myelolipoma: Case report and review of the literature

INTRODUCTION

Bilateral adrenal myelolipoma is a rare benign neoplasm. We presented the case of a young man affected by a bilateral myelolipoma and the analysis of the literature of bilateral cases of myelolipoma. Our purpose is to give a suggestion of clear terms of reference regarding the management of this kind of bilateral neoplasm.

PRESENTATION OF CASE

We reported the case of a 41-year-old healthy man complained of abdominal pain in the upper quadrants. No significant alterations were found in routine blood and endocrinological tests. The imaging (CT and MRI) showed a huge right adrenal mass and a smaller lesion at the left adrenal gland. The preoperative pathological characterization was suggestive for a myelolipoma. A right open adrenalectomy was performed, and a radiological surveillance was planned for the left tumor. The pathological exam confirmed the diagnosis.

DISCUSSION

In literature, there are 36 cases described. The clinical presentation consisted of symptomatic tumors, incidentally diagnosed lesions or myelolipomas in patients with an associated endocrinal disorder. Symptomatic tumors or those bigger than 7cm, because of the potential risk of rupture, are usually treated surgically. In smaller (<7cm) and asymptomatic ones the surgical treatment is not univocal.

CONCLUSION

In the setting of the surgical treatment, it is important to preserve in some way the hormonal function. For that reason, the bilateral adrenalectomy has to be reserved for symptomatic or sizeable (>7cm) cases. As far as we know, this is the first review on bilateral myelolipomas.

Rare adrenal gland emergencies: a case series of giant myelolipoma presenting with massive hemorrhage and abscess

INTRODUCTION

Adrenal Myelolipoma is a rare benign neoplasm, which contains mature adipose tissue and variable amounts of haematopoietic elements. Most lesions are small and asymptomatic, discovered incidentally during autopsy or imaging studies performed for other reasons.

CASE PRESENTATION

Here we reported a series of two cases of giant myelolipomas of the adrenal gland; first one the largest tumor reported so far presented with massive hemorrhage and the second case introduced with its rare unreported presentation of adrenal myelolipomas i.e. a large abscess.

DISCUSSION

Adrenal myelolipoma is a rare and asymptomatic tumor usually discovered incidentally in less than 1% of population on autopsy or imaging performed for other reasons. There is an increasing incidence of large adrenal myelolipoma (> 10 cm) presenting with life threatening and recurrent retroperitoneal hemorrhage along with other complications as abscess. To avoid such a life-threatening situation, authors recommend close monitoring and consideration of urgent surgical intervention for tumors larger than 4 cm at presentation or increase in size or change in appearance during follow-up.

Radiologic-pathologic correlation in extra-adrenal myelolipoma

Myelolipoma is an uncommon benign tumor that classically arises in the adrenal glands. Most cases are asymptomatic, with incidental detection of this tumor on cross-sectional imaging performed for other causes. Extra-adrenal occurrence of myelolipoma has been infrequently reported, with scarce radiology literature on the topic. We present radiologic and pathologic correlation in two cases of image-guided biopsy proven extra-adrenal myelolipoma in the presacral and paraaortic location, with review of literature.

Giant adrenal myelolipoma: when trauma and oncology collide

Three patients presented some decades after severe traumatic injury with atypical bowel symptoms which were caused by a giant myelolipoma of the adrenal gland. The aetiology of this rare, benign and generally asymptomatic tumour is virtually unknown at present and several hypotheses have been devised. This report describes a possible association between high-energy trauma and the development of giant myelolipomas, further contributing to the hypothesis that severe systemic stress could be an aetiological factor in the development of an adrenal myelolipoma.

Giant adrenal myelolipoma masquerading as heart failure

Adrenal myelolipomas are rare benign tumors of the adrenal cortex composed of adipose and hematopoietic cells. They have been postulated to arise from repeated stimulation by stress, inflammation and ACTH oversecretion. Myelolipomas are usually detected incidentally on imaging and do not require any active intervention besides regular follow-up by imaging. However, myelolipomas may insidiously grow to large sizes and cause mass effects and hemorrhage. Timely diagnosis and surgical resection are curative and lifesaving.

Late-onset congenital adrenal hyperplasia with Cushing syndrome

Although hirsutism is classically part of the clinical presentation of polycystic ovarian syndrome (PCOS), congenital adrenal hyperplasia and Cushing's syndrome (CS), CS associated with underlying late-onset congenital adrenal hyperplasia (LCAH) in an adult has not been previously reported. We herein present the case of a 25-year-old woman who was followed for PCOS for seven years. After undergoing detailed tests described within the text, she received the diagnosis of LCAH and was found to have point mutations. Interestingly, she later had diagnosis of endogenous CS that regressed folowing excision of an adrenal adenoma found on MRI. The present patient thus exhibited the coexistence of two paradoxical endocrine pathologies.

A 10-year single-center experience with surgical management of adrenal myelolipoma

OBJECTIVE

The purpose is to report our 10-year experience with surgical management of large or symptomatic adrenal myelolipoma.

PATIENTS AND METHODS

Patients receiving surgical treatment for adrenal myelolipoma between December 2001 and September 2011 in our institution were retrospectively reviewed. Patients were divided into two groups: open surgery and laparoscopic surgery. Patient demographic data, lesion size evaluated by computed tomography scan or magnetic resonance imaging, operation time, blood loss, time of returning to diets, perioperative complications, and length of hospital stay were collected and analyzed.

RESULTS

Forty patients (14 received open surgery and 26 received laparoscopic surgery) were enrolled in our study. Both procedures were successful and no patient in the retroperitoneal laparoscopic group required conversion to open surgery. The mean age of the patients was 52.7 years. The median size of the tumor was 5.0 cm. Forty-three percent of patients suffered from lumbago. There was no statistical difference in perioperative complications between the two groups (p>0.05). Retroperitoneal laparoscopic adrenalectomy patients had a shorter operation time (90.66±37.97 min vs 141.82±62.78 min, p=0.017), less blood loss (150, 100-200 mL vs 450, 300-525 mL, p=0.000), earlier time of returning to diets (2, 2-3 days vs 3, 2-4.5 days, p=0.036), and a shorter hospital stay (6, 5-7 days vs 10, 8-11.25 days, p=0.000) when compared with open surgery patients.

CONCLUSION

Both open and laparoscopic surgeries are efficient and safe treatments for large or symptomatic adrenal myelolipoma, and retroperitoneal laparoscopic surgery has the advantages of minimal invasion and rapid postoperative recovery.

Adrenal myelolipoma: operative indications and outcomes

BACKGROUND

Adrenal myelolipoma (AM) is a benign lesion for which adrenalectomy is infrequently indicated. We investigated operative indications and outcomes for AM in a large single-institution series.

SUBJECTS AND METHODS

A retrospective cohort study of prospectively collected data was conducted. Patients (≥16 years of age) who underwent adrenalectomy in the Division of General Surgery at Barnes-Jewish Hospital (1993-2010) were grouped by operative indication (myelolipoma versus other pathology) and compared using nonparametric tests (α<0.05).

RESULTS

Sixteen patients (4.0%) had myelolipomas resected out of 402 patients who underwent adrenalectomy. Fourteen patients with suspected AM underwent adrenalectomy, 13 (93%) of whom had AM confirmed on pathology. Indications for adrenalectomy were abdominal or flank pain, large tumor size (>8 cm), atypical radiologic appearance, and/or inferior vena cava compression. Three patients with suspected other adrenal lesions had AM confirmed on final pathology. Operative approach was laparoscopic in 15 cases and open in 1 case of a 21-cm lesion. Patients who underwent laparoscopic adrenalectomy for AM (n=15) or other adrenal pathology (n=343) were similar with respect to age, gender, American Society of Anesthesiologists classification, prior abdominal operation, tumor side, operative time, conversion rate, estimated blood loss, intraoperative complications, hospital length of stay, and 30-day morbidity. However, patients with resected AM had a higher body mass index (36.5±8.1 kg/m(2) versus 30.1±7.5 kg/m(2); P<.01) and a larger preoperative tumor size (8.4±3.0 cm versus 3.1±1.7 cm; P<.01).

CONCLUSIONS

Laparoscopic adrenalectomy may be appropriate for patients with a presumptive diagnosis of AM and abdominal or flank pain, large tumor size, and/or uncertain diagnosis after imaging. Outcomes and morbidity following LA for AM and other adrenal pathology appear comparable.

Incidental detection of adrenal myelolipoma: a case report and review of literature

Introduction. Adrenal myelolipoma is a rare tumor that is benign in nature, usually asymptomatic, unilateral, and nonsecreting. It is composed of variable mixture of mature adipose tissue and hematopoietic elements and develops within the adrenal gland. With the widespread use of cross-sectional imaging modalities such as ultrasonography and computed tomography, the incidental detection of these tumors is increasing in frequency. Case Presentation. We report a case of adrenal myelolipoma in a 63-year-old Kashmiri male, who presented with pain in the right upper abdomen. Physical examination was unremarkable. Ultrasound abdomen showed the presence of a hyperechoic mass in the right suprarenal region with undefined margins. Contrast-enhanced computed tomography (CECT) scan of abdomen revealed a well-defined, round lesion in the right suprarenal region with heterogeneous attenuation suggesting the possibility of myelolipoma. The patient was subjected to right adrenalectomy and his postoperative course was uneventful. The histopathological evaluation of the mass confirmed the initial diagnosis of adrenal myelolipoma. Conclusion. Although mostly discovered as an "incidentaloma", the diagnosis of adrenal myelolipoma warrants thorough diagnostic study. Imaging techniques such as ultrasonography and CT scans as well as biochemical studies are useful for indicating the best treatment taking into account the size of the mass and possible hormone production. Surgical resection is advocated through extraperitoneal approach as it minimizes postoperative complications and leads to quicker recovery.

Myelolipomas and other fatty tumours of the adrenals

Background

Lipomatous tumours of the adrenals are almost always benign. The importance of recognising their characteristic radiological features, leading to their correct treatment, is fundamental, as there has been an increase in the identification of these lesions. Our goal was to review all lipomatous tumours of the adrenal glands, particularly myelolipomas, their imaging methods and surgical management, updated in 2011.

Methods

This was a retrospective review of articles published in the USA and Europe, from 1979 to date. The sites from which information was retrieved covered PubMed, Medscape, Clinical Imaging, Histopathology, Urologia Internationalis, Archives of Surgery, JACS, the American Urological Association, BMJ, Medline, and Springer Link. We report areas of controversies in addition to well established guidelines.

Results

We reviewed 45 articles, that confirmed, with a high level of evidence-based medicine, that the diagnosis of a lipomatous adrenal tumour is made by various imaging procedures, particularly computed tomography (CT). We emphasise the importance to their management of the initial size of the adrenal mass, its increase in size over time, in addition to the presence of symptoms.

Conclusion

Lipomatous tumours of the adrenals are most frequently benign. The diagnosis is usually made by various techniques, in particular CT. The fundamental characteristics indicating the necessity of surgical intervention are the symptoms presented, volume of the tumoral mass (>5 cm), and the increase in size of the tumour as shown in two consecutive imaging studies.

Intraosseous myelolipoma within proximal femoral metaphysis in a patient with previous prostate cancer: a case report

We report on a case of an osteolytic lesion of the femur in a patient with previous prostate cancer, affected by hip osteoarthritis. Computed tomography of the femur demonstrated the presence of fat in the lesion. Computed tomography-guided fine needle aspiration biopsy revealed mature adipose tissue along with hematopoietic precursor cells. Surgical management consisted of curettage and packing with allograft, followed later by total hip arthroplasty. This is the third case of intraosseous myelolipoma reported in the literature.

Adrenal mass imaging with multidetector CT: pathologic conditions, pearls, and pitfalls

The adrenal gland is involved by a range of neoplasms, including primary and metastatic malignant tumors; however, the most common tumor detected is the incidental benign adenoma. Although computed tomographic (CT) findings will not always yield a definitive diagnosis, attention to these findings provides a road map to guide image interpretation. Adenomas typically demonstrate rapid washout, which is defined as an absolute percentage washout (APW) of more than 60% and a relative percentage washout (RPW) of more than 40% on delayed images. Adrenocortical carcinoma typically has an RPW of less than 40%; however, large size and heterogeneity are more reliable indicators of the diagnosis than are washout values. Washout characteristics of pheochromocytoma are variable; in conjunction with high levels of dynamic enhancement, pheochromocytomas may mimic adenoma (ie, APW > 60%, RPW > 40%). Myelolipomas appear as well-defined masses with variable quantities of fat and soft tissue. After contrast material administration, metastases usually demonstrate slower washout on delayed images (APW < 60%, RPW < 40%) than do adenomas, although hypervascular metastases may enhance similarly to pheochromocytoma. Finally, a number of nonadrenal pathologic conditions have been reported to mimic adrenal masses at CT.

Adrenal imaging with multidetector CT: evidence-based protocol optimization and interpretative practice

Computed tomography (CT) is an integral tool in the assessment of adrenal masses. Dedicated adrenal CT is performed for a range of indications, including hormonal abnormalities suggestive of a functional adrenal mass and adrenal cancer staging. It is important to have an understanding of the published data that guide protocol design and image interpretation. Whether an adrenal mass is identified serendipitously or is being imaged for further characterization, there are several CT findings that contribute to the diagnosis, such as lesion size, precontrast attenuation, level of enhancement at 60 seconds and on delayed images, percentage washout on delayed images, histogram analysis, and extent (involvement of the inferior vena cava and bilaterality). In the past decade, a body of pertinent literature has evolved, addressing each of these measures individually.

[Hepatic myelolipoma. Diagnosis and treatment]

Myelolipoma is a very uncommon tumor and is extremely rare in the liver. Patients are usually asymptomatic and preoperative diagnosis is often difficult. We report a new case of hepatic myelolipoma and review all the cases previously reported in the literature. Clinicopathologic and radiologic findings, as well as therapeutic options, are discussed.

Adrenal myelolipoma within myxoid cortical adenoma associated with Conn's syndrome

The coexistence of myelolipoma within adrenal cortical adenoma is extremely rare, for both tumors present usually as separate entities. There are only 16 such cases reported worldwide. To the best of our knowledge, the case we reported here is the first one of myxoid adrenal cortical adenoma associated with myelolipoma reported. A 32-year-old Chinese woman with 4-year history of hypertension was presented in our study. Computed tomography (CT) of the abdomen showed a large heterogeneously-enhancing mass (4.5 cm in diameter) in the left suprarenal region. Clinical history and laboratory results suggest a metabolic disorder as Conn's syndrome. The patient underwent a left adrenalectomy, and a histopathological study confirmed the mass to be a myxoid adrenal cortical adenoma containing myelolipoma. The patient was postoperatively well and discharged uneventfully. In the present case report, we also discuss the etiology of simultaneous myelolipoma and adrenal adenoma associated with Conn's syndrome, and the methods of the diagnosis and differential diagnosis.

Asymptomatic bilateral giant adrenal myelolipomas: case report and review of literature

OBJECTIVE

To describe an unusual case of bilateral giant adrenal masses caused by a primary adrenal myelolipoma.

METHODS

We present the clinical, laboratory, and pathologic findings in a 32-year-old man with bilateral adrenal masses. The previous reports of bilateral myelolipomas also were reviewed.

RESULTS

During a routine examination, a 32-year-old Thai man was found to have an asymptomatic abdominal mass. A computed tomographic scan of the abdomen disclosed bilateral adrenal masses; the one on the left was approximately 27 by 24 by 12 cm, and the one on the right side was 9 by 5 by 5 cm. The computed tomographic scan characteristics showed that both masses consisted mainly of low-density tissues (-30 to -90 Hounsfield units), suggestive of fatty component. An endocrinologic evaluation revealed no evidence of adrenal cortical or medullary functional abnormalities. Bilateral adrenalectomy was performed because of the large size of the lesions and the inability to rule out malignant involvement.

CONCLUSION

Myelolipoma is a relatively rare benign tumor of the adrenal glands composed of adipose cells and mature hematopoietic elements. Most such lesions are small, asymptomatic, and unilateral; giant or bilateral myelolipomas are quite rare. To our knowledge, our current case may represent the largest bilateral lesions in the literature.

Primary Retroperitoneal Teratoma Presenting as an Adrenal Tumor in an Adult

Primary teratomas in the retroperitoneum are rare in adults. Most teratomas in this region are secondary to germ cell tumors of the testes or ovaries. We describe a case of mature cystic teratoma that was clinically suggestive of an adrenal myelolipoma. Resection was attempted using laparoscopy but was converted to open adrenalectomy to ensure complete resection. Because of the risk of malignancy, follow-up radiographic studies were performed to ensure the oncologic efficacy of resection. The patient has been free of recurrence for longer than 18 months.

Adrenal myelolipomas show nonrandom X-chromosome inactivation in hematopoietic elements and fat: support for a clonal origin of myelolipomas

Myelolipomas are defined as mature fat associated with hematopoietic elements, often found in the adrenal gland. The question of whether the hematopoietic cells are truly "normal" has not been evaluated extensively. In this study, we evaluated histologic, immunohistochemical features and comparisons of X-chromosome inactivation patterns in 19 myelolipomas. Formalin-fixed, paraffin-embedded tissue from 19 myelolipomas was stained with hematoxylin and eosin and immunostained with monoclonal antibodies against CD138, CD34, CD117, CD42a, hemoglobin, myeloperoxidase, collagen IV, and nerve growth factor receptor. Histologic evaluation included estimates of overall cellularity of hematopoietic tissue, estimates of cellularity in the areas of highest concentration of hematopoietic tissue, myeloid to erythroid ratio, and numbers of megakaryocytes. X-chromosome inactivation analysis was performed on myelolipomas from 11 female patients by polymerase chain reaction. Myelolipomas showed wide variation in cellularity within the lesion (5% to 90%) with no correlation with the patient's age. All the myelolipomas demonstrated normal trilineage hematopoiesis and cellular morphology, with few early myeloid precursors, as evidenced by negativity for CD117 and only rare positivity for CD34 antibodies. Most of the myelolipomas (14/18) had markedly increased megakaryocytes compared with normal marrows. The majority of myelolipomas also had a stromal composition and vascular patterns that were different from those of normal bone marrow. X-chromosome inactivation studies demonstrated nonrandom X-chromosome inactivation in 8/11 myelolipomas from female patients. Myelolipomas are morphologically different from the normal bone marrow. The majority of myelolipomas also have nonrandom X-chromosome inactivation, suggesting a clonal origin for these tumors.