Adrenal lipoma. A case report

Imaging features of adrenal masses

The widespread use of imaging examinations has increased the detection of incidental adrenal lesions, which are mostly benign and non-functioning adenomas. The differentiation of a benign from a malignant adrenal mass can be crucial especially in oncology patients since it would greatly affect treatment and prognosis. In this setting, imaging plays a key role in the detection and characterization of adrenal lesions, with several imaging tools which can be employed by radiologists. A thorough knowledge of the imaging features of adrenal masses is essential to better characterize these lesions, avoiding a misinterpretation of imaging findings, which frequently overlap between benign and malignant conditions, thus helping clinicians and surgeons in the management of patients. The purpose of this paper is to provide an overview of the main imaging features of adrenal masses and tumor-like conditions recalling the strengths and weaknesses of imaging modalities commonly used in adrenal imaging.

Lipomatous tumours in adrenal gland: WHO updates and clinical implications

Adrenal lipomatous tumour is a group of adrenal tumours with a significant component of adipose tissue. According to the current World Health Organization (WHO) classification of tumours of endocrine organs, adrenal myelolipoma is the only entity amongst the group of tumours being described. In the literature, other more recently documented adrenal lipomatous tumours included 24 lipomas, 32 teratomas and 16 angiomyolipomas. Rare fatty tumours of the adrenal gland comprised liposarcoma, hibernoma, adrenocortical tumours with fat component and rare adrenal tumours with fat component. Myelolipoma comprises approximately 3% of primary adrenal tumour. It is noted more commonly in females and in the right adrenal gland. Approximately 40 bilateral myelolipomas were reported. The tumour is most frequently recorded in patients between fifth and seventh decades of life. Adrenal lipomas are often seen in males and in the right adrenal gland. They were commonly noted in patients in the sixth decade of life. The diagnosis could only be possible on examination of the surgically removed specimen. Adrenal teratomas were more common in females and with a bimodal age distribution. Slightly over 60% of the patients with adrenal teratoma are symptomatic. Adrenal angiomyolipomas were often symptomatic, more common in females and in the fifth decades of life. To conclude, adrenal lipomatous tumour is uncommon. They are often benign and non-functional. It is important to recognize the features of this group of lipomatous tumours in the adrenal gland as they are being detected on increasing incidence as a result of the wide-spread use of modern imaging modalities.

The diagnosis and treatment of primary adrenal lipomatous tumours in Chinese patients: A 31-year follow-up study

INTRODUCTION

Adrenal lipomatous tumours (ALTs) are rarely encountered in clinical practice and consequently little is known about their clinical features.

METHODS

We analyze the clinical features, diagnosis and treatment of ALTs based on cases presenting at a single centre over a 31-year period. We reviewed clinical data from patients with primary adrenal tumours treated at the Ruijin Hospital, Shanghai between January 1980 and December 2010.

RESULTS

A total of 73 cases of primary ALTs in 22 men and 51 women (mean age 51.1±14.2 years) were reviewed. The ALTs included 65 myelolipomas (89.0%), 3 lipomas (4.1%), 2 angiomyolipomas (2.7%), 2 teratomas (2.7%), and 1 liposarcoma (1.4%). Of the total 73 patients, 24 of them had tumours in the left adrenal gland, 47 in the right gland and 2 had bilateral tumours. In total, 51 patients underwent open surgery and 22 laparoscopic surgery.

CONCLUSION

Myelolipoma is predominant among the various types of lipomatous adrenal gland tumours; it accounts for about 90% of all cases. Surgery is recommended for tumours ≥3.5 cm in diameter, for all cases of symptomatic tumour, and for cases of teratoma or liposarcoma identified by preoperative imaging.

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.

A giant adrenal lipoma presenting in a woman with chronic mild postprandial abdominal pain: a case report

Introduction

Adrenal lipomas are rare, small, benign, non-functioning tumors, which must be histopathologically differentiated from other tumors such as myelolipomas or liposarcomas. They are usually identified incidentally during autopsy, imaging, or laparotomy. Occasionally, they may present acutely due to complications such as abdominal pain from retroperitoneal bleeding, or systemic symptoms of infection. We report a giant adrenal lipoma (to the best of our knowledge, the second largest in the literature) clinically presenting with chronic mild postprandial pain.

Case presentation

A 54-year-old Caucasian woman presented several times over a period of 10 years to various emergency departments complaining of long-term mild postprandial abdominal pain. Although clinical examinations were unrevealing, an abdominal computed tomography scan performed at her most recent presentation led to the identification of a large lipoma of the left adrenal gland, which occupied most of the retroperitoneal space. Myelolipoma was ruled out due to the absence of megakaryocytes, immature leukocytes, or erythrocytes. Liposarcoma was ruled out due to the absence of lipoblasts. The size of the lipoma (16 × 14 × 7 cm) is, to the best of our knowledge, the second largest reported to date. After surgical resection, our patient was relieved of her symptoms and remains healthy six years postoperatively.

Conclusion

Physicians should be aware that differential diagnosis of mild chronic abdominal pain in patients presenting in emergency rooms may include large adrenal lipomas. When initial diagnostic investigation is not revealing, out-patient specialist evaluation should be planned to enable appropriate further investigations.

Acute abdominal pain secondary to retroperitoneal bleeding from a giant adrenal lipoma with review of literature

Adrenal lipomas are rare, non-functioning benign tumours, which are primarily detected during autopsy or imaging, as asymptomatic incidentalomas. Occasionally, they can present with abdominal pain due to their large size. Imaging studies help to determine the origin, volume, composition of the lesion and presence of bleeding. Histopathology, however, is necessary to differentiate an adrenal lipoma from other fatty tumours such as myelolipoma, angiomyolipomas, teratomas and liposarcomas. We report a case of spontaneous bleeding from a giant adrenal lipoma that presented as an acute abdomen, and was initially mistaken on imaging for the more common myelolipoma. The literature is reviewed to discuss the clinical, pathological and radiological features, and the optimum therapeutic management.

Adrenal lipomatous tumours: a 30 year clinicopathological experience at a single institution

AIMS

Fatty tumours of the adrenal gland are uncommon and their features have received little attention in the literature. The aim of this study is to analyse the features of adrenal lipomatous tumours.

METHODS

The histological features of primary adrenal tumours reported over a 30 year period (1970 to 1999) in Queen Mary Hospital, Hong Kong were reviewed and the clinicopathological features of adrenal lipomatous tumours were analysed.

RESULTS

Adrenal lipomatous tumours were noted in 20 patients (12 men, eight women), and they accounted for 4.8% of the primary adrenal tumours reported. The adrenal fatty tumours comprised 11 myelolipomas, three lipomas, three teratomas, two angiomyolipomas, and one liposarcoma. Calcification or bone was noted in one third (seven of 20) of the adrenal tumours. In some fatty tumours (myelolipoma and angiomyolipoma), the fatty component may be inconspicuous. This is the first report in the English literature of angiomyolipoma and liposarcoma of the adrenal gland.

CONCLUSIONS

Different types of fatty tumours were noted in the adrenal gland. A high index of suspicion should be maintained with an aim of surgical treatment for selected patients with large and symptomatic adrenal lipomatous lesions. Histological confirmation is needed for diagnosis.

Lipoma of the adrenal gland

A rare case of a lipoma of the adrenal gland is reported with a review of the literature. The tumor was incidentally found at autopsy in a 50-year-old man who died from severe head trauma after a traffic injury. At autopsy, an oval-shaped, soft yellow nodule measuring 1.1 cm in diameter was found in the right adrenal cortex. Histological examination revealed a lesion consisting of mature adipose tissue partially surrounded by a thin fibrous capsule. On serial sections there was no evidence of hematopoiesis nor of adrenal medulla cells. To the best of our knowledge, this is the eighth case described in the English literature. With the increasing use and the high resolution of modern imaging techniques, these unsuspected adrenal masses may become more prevalent.