Adrenal adenoma and hematoma mimicking a collision tumor at MR imaging

Adrenal Adenoma-Hemangioma Collision Tumor: Description of Two Cases

Adrenal collision tumors are rare clinical entities referring to separate coexisting adjacent tumors involving an adrenal gland with sharp demarcation between the two and without a substantial histologic admixture at the interface. Most of the adrenal collision tumors described are combinations of adenoma and metastasis or adenoma and myelolipoma. We report two cases of a 63-year-old male and a 76-year-old female patient with a presumable exceedingly rare adrenal hemangioma-adenoma collision tumor. To our knowledge, only two reports of a collision tumor comprising an adrenal hemangioma and an adenoma have been described in literature.

Adrenal collision tumors and their mimics: multimodality imaging findings

Adrenal collision tumors (ACTs) refer to coexistence of two adjacent, but histologically distinct neoplasms involving the adrenal gland without histologic admixture at interface. ACTs include adenoma with myelolipoma, adenoma with metastases, hemangioma with adenoma, and adrenocortical carcinoma with myelolipoma. In addition, hemorrhage into a pre-existing adrenal mass can mimic an ACT, and it is important to differentiate these two pathologies. Accurate characterization of ACTs is difficult, but critical, for correct staging of patients with malignancies and to guide percutaneous biopsy. Magnetic resonance imaging (MRI) and multidetector computed tomography imaging techniques may depict different tumor components separately; however, biopsy may be required in selected patients for confirmation. [¹⁸F]Fluorodeoxyglucose-positron emission tomography (PET) shows increased uptake in the malignant component of ACTs, and guides percutaneous biopsy. Even in patients requiring percutaneous biopsy for a definite diagnosis, imaging findings can help in guiding the appropriate component to be biopsied. Knowledge of imaging findings of different ACTs and their mimics on MRI, computed tomography, and PET help in optimal patient management.

Corticomedullary mixed tumor of the adrenal gland-a clinical and pathological chameleon: case report and review of literature

Adrenal tumors mostly present with specific and unique clinical features, regarding their endocrine metabolism. A 53-year-old man came to our Department for a left adrenal mass discovered incidentally. Biochemical and imaging findings were suspicious for a pheochromocytoma. The patient underwent a laparoscopic left adrenalectomy. A well-circumscribed 5.5-cm mass was removed. It was composed of adrenal cells intimately admixed with pheochromocytes. Immunohistochemical studies were positive both for cortical cells (inibin-α, synaptophysine and melan-A) and medullary cells (S-100 and chromogranine A). Final pathology was of corticomedullary mixed tumor (CMT). CMT is a rare tumor with 14 cases previously reported in literature, with wide variable biochemical behavior, such as his radiological and pathological features. Prevalence and actual malignant potential are yet unknown to our knowledge.

Adrenal adenoma with organizing hematoma: diagnostic dilemma at MRI

We report a case of adrenal adenoma with organizing hematoma mimicking hemangioma on magnetic resonance imaging (MRI). The lesion demonstrated heterogeneous hyperintensity on heavily T2-weighted images. On dynamic contrasted-enhanced MRI, the lesion demonstrated early, patchy peripheral enhancement with subsequent fill-in that persisted. Chemical shift gradient-echo images failed to demonstrate the presence of intracellular lipid. Magnetic resonance imaging failed to characterize the lesion, and an erroneous preoperative diagnosis of adrenal hemangioma was made. Although the MRI findings reflected the organized hematoma with abundant vascular spaces, our case emphasizes the point that the MRI characteristics of intratumoral hemorrhage may overlap with those of adrenal hemangioma and chronic expanding hematoma.

MR imaging of the adrenal glands

MR imaging is used commonly for imaging the adrenal glands. Its high-contrast resolution and multiplanar imaging capability enables the detection and characterization of many adrenal masses. The advent of chemical-shift imaging revolutionized the role of MR imaging in characterizing adrenal masses. In this article, the authors discuss the range of MR appearances of common and uncommon adrenal masses, focusing on the nonfunctioning incidentally discovered mass and its characterization methods. MR imaging is continuously improving. The increasing use of higher strength magnets and the introduction of newer coils, sequences, and techniques will help detect and characterize very small adrenal masses, quantify their fat content, and provide exquisite morphologic images of the gland and its vascular supply.