A collision between vascular adrenal cyst and adrenocortical adenoma

We report a patient with sigmoid colon cancer who revealed a unique collision of hemorrhagic vascular adrenal cyst and adrenocortical adenoma with myelolipomatous changes. Two months before referral to our hospital, anticoagulant therapy was started for acute myocardial infarction. The components of the adrenocortical adenoma demonstrated a typical signal drop in opposed-phase magnetic resonance (MR) images although macroscopic fat was also depicted both on CT and MR images. The components of the vascular adrenal cyst demonstrated peripheral nodular enhancement with progressive enhancement on dynamic contrast-enhanced CT and a hemorrhagic change in the central region, which showed hyper intensity on T1-weighted images (T1WI) and hypo intensity on T2-weighted images (T2WI). Microscopically, the cyst was filled with foci of hemorrhage, fibrin, fibrosis, and hemosiderin. Furthermore, a white thrombus was found that corresponded to the central low signal intensity depicted on T2WI. Dilated vascular channels that were immunohistochemically positive for CD31 and CD34 were identified within the cyst. They were consistent with the pathological findings of hemorrhagic vascular adrenal cyst. Radiologists should be aware that the diagnosis of adrenal vascular cyst could be challenging since image findings may resemble hemangiomas, pheochromocytomas, and malignancy.