Myelolipoma: A Rare Adrenal Incidentaloma

Abstract

Case ReportOpen Access IntroductionMyelolipomas are rare, benign tumors composed of mature adipose tissue and hematopoietic elements (myeloid and erythroid cells) [1]. We describe a case of dual pathology where adrenal incidentaloma was successfully treated. Case ReportA 40-year-old lady was referred to surgical outpatient clinic with an ultrasonologically detected adrenal mass, while being investigated for menorrhagia with a large pelvic mass. She did not have any symptoms related to the adrenal mass and was normotensive. Further biochemical investigations directed to adrenal pathology revealed a normal urinary VMA level, serum electrolytes and cortisol levels. The initial ultrasound scan suggested a well-defined, hyperechoic SOL in the left suprarenal region (94 x 80 mm) suggestive of a lipomatous tumour, along with a large intrauterine fibroid (119 x 96 mm). Subsequently, CECT of the abdomen revealed a large, well defined, mildly & heterogeneously enhancing mass lesion showing attenuation value of fat, involving left adrenal gland, suggestive of myolipoma (Figures 1 and 2). The right suprarenal was normal. In view of the large size of the uterine tumour and the fact that menorrhagia was under control, she underwent left adrenalectomy only in the first sitting, through a modified chevron incision. Macroscopical cut section of the specimen showed homogenous yellow surface with reddish streaking. Histopathology of the specimen revealed features of myelolipoma. She had an uneventful recovery and doing well now at six months follow up. Discussion and ConclusionEdgar von Gierke first described this lesion in the adrenal in 1905 but it was named, "myelolipoma", by Charles Oberling [2,3]. The adrenal gland is the most common site, but myelolipomas also (rarely) occur in extra-adrenal sites (14% of myelolipomas are extraadrenal [4]) including the pelvis, mediastinum, retroperitoneum, and paravertebral region, as an isolated soft tissue mass [5].It is usually hormonally inactive, and found in 0.08 to 0.2% of autopsy series [6,7] but comprise up to 15% of adrenal incidentalomas with the increasing use of noninvasive imaging [8] and account for 2.6% of all primary adrenal tumours [9]. Myelolipomas, affect both sexes equally and usually occur during fifth and seventh decades of life [10]. Adrenal myelolipomas are in the majority of cases unilateral. However, they can also be bilateral [11]. Adrenal myelolipomas may be found coincidentally with other lesions in the adrenal glands, such as adenomas and less commonly with pheochromocytoma or metastases. These cases are described as "collision tumours" [12].Adrenal myelolipomas vary in size, from several millimetres to more than 30 cm, and usually in the range of 2-10 cm in diameter [1,13]. The term giant myelolipoma is preferred when the size exceeds 8 cm [14], as seen in our case. AbstractBackground: Myelolipoma is a rarely encountered, adrenal incidentaloma diagnosed on the basis of its radiological features.Aim: To describe a rare presentation with dual pathology.Case p...