​Primary retroperitoneal pseudocyst: beware of the hoax solid enhancing adrenal mass.

​We report the case of a 55-year-old male patient with an incidental finding on CT of a 'large adrenal mass'. The mass, which was intimately related to the left adrenal, was enhancing but not metabolically active. CT showed a 40×32 mm mass adjacent to the left adrenal and medial border of the spleen, 32 Hounsfield units (HU) precontrast and 116 HU postcontrast, consistent with a solid enhancing mass. The patient had no previous history of acute pancreatitis or any history of trauma. The patient proceeded to a laparoscopic left adrenalectomy; intraoperatively, a well-circumscribed lesion was identified intimately related to the splenic artery and able to be peeled away easily from the left adrenal. The lesion was unable to be dissected from the splenic artery and consequently the splenic artery was divided in order to completely resect this lesion. Histopathology identified the lesion as a 'non-pancreatic fibrous pseudocyst', with a thick calcified wall, the absence of epithelial lining and widespread inflammatory change. © BMJ Publishing Group Limited 2019. No commercial re-use. See rights and permissions. Published by BMJ.