Not Every Hypermetabolic Nonfunctioning Adrenal Mass is Malignant - A Case Report of Adrenal Hemangioma

A routine abdominal ultrasound study in a 49-year-old man with chronic hepatitis C (history of intravenous drugs consumption) revealed a solid and heterogeneous mass on the right adrenal gland. He was asymptomatic and the laboratory tests were normal. A Computed Tomography (CT) was performed to characterize the adrenal lesion.

Abdominal unenhanced CT showed a right adrenal large solid lesion (7,2 x 4,6 cm), with soft-tissue attenuation (35 HU) and multiple and coarse calcifications (Fig. 1). Contrast-enhanced CT scan demonstrated heterogeneous and peripheral enhancement with gradual and centripetal filling in the late acquisition (Fig. 2 and Fig. 3).

The lesion was well-circumscribed, and there were no signs of extra-adrenal invasion. The left adrenal gland was normal.

Additionally, a Positron Emission Tomography - Computed Tomography (PET-CT) scan revealed heterogeneous uptake of 18-FDG in the right adrenal gland, with mild to moderate peripheral metabolism and central photopenia (Fig. 4).

MR study could not be performed due to a previous metallic gunshot foreign body on the patient´s skull.

Adrenal cavernous hemangioma is a rare benign tumour, usually discovered incidentally on abdominal imaging. The definitive diagnosis is largely established postoperative after specimen examination [1, 2].

Incidental adrenal masses are being diagnosed more frequently due to the widespread use of abdominal cross-sectional imaging, estimated to occur in 3-7% of adults [3]. Imaging characteristics as well as laboratory findings are utilized to further define these incidentalomas and distinguish functional and nonfunctional benign and malignant tumours [4].

Adrenal hemangiomas generally present in the sixth to seventh decade of life and are more frequent in women, with a male-female ratio of 2:1 [1]. They tend to be asymptomatic non-functioning tumours. Rarely, they may rupture leading to retroperitoneal haemorrhage [5].

Adrenal cavernous hemangioma should be considered in the differential diagnosis of a nonfunctioning adrenal mass along with a lipid-rich or lipid poor adenoma, a ganglioneuroma, adrenal cortical carcinoma and metastases [4].

Abdominal CT and MRI are valuable diagnostic tools for hemangiomas. Contrast-enhanced CT exhibit characteristic peripheral patchy and centripetal enhancement and highly dense peripheral rim. In the absence of centripetal enhancement, the diagnosis is difficult because thin-rim peripheral enhancement may be observed in other adrenal tumours [2, 6]. The presence of calcifications throughout the tumour are seen also in other adrenal tumours. Moreover, the large size, lack of evidence for microscopic fat and minimal or no contrast washout are characteristic of malignant lesion that may, as well, be seen in hemangiomas [4, 5].

The majority of the adrenal hemangioma is hyperintense on T2-weighted images on MRI, with focal hyperintensity on T1-weighted images due to bleeding and calcifications [2, 5, 6].

In general, adrenalectomy is recommended for an adrenal mass > 4 cm because of concern for adrenal cortical carcinoma and for an isolated adrenal metastasis, regardless of its endocrine activity [3, 5]. Needle biopsy is rarely indicated for evaluation of an incidentally discovered adrenal mass, except in patients with known underlying malignancy to make a diagnosis of metastatic disease [3, 4].

In this case, the patient underwent a right adrenalectomy and the histopathological evaluation revealed a benign cavernous hemangioma with associated adrenal cortical hyperplasia. No evidence of hepatic nor other peritoneal lesions was present.

Written informed patient consent for publication has been obtained.