Effectiveness of gallium scintigraphy in diagnosing a spontaneous giant chronic expanding hematoma of the adrenal gland: A case report

•A chronic expanding hematoma of the adrenal gland is extremely rare.•Chronic expanding hematomas mimic sarcomatous lesions.•Gallium scintigraphy may help the differential diagnosis between chronic expanding hematomas and sarcomatous lesions.•Complete resection of chronic expanding hematomas is the gold standard.•Preoperative arterial embolization may reduce intraoperative bleeding on complete tumor removal.