MON-206 Diagnosis of Non-Functional Masses in Adrenal Gland Topography - Experience of a Tertiary Health Center

Introduction: Masses in adrenal topography are diagnosed frequently due to the increase in radiological imaging in clinical practice. Adrenal incidentalomas occur between 4% and 10% of the patients above 50 years undergoing abdominal imaging, and the majority are benign pathologies. Objective: To analyze the characteristics of the masses located in adrenal gland topography not originating from the adrenal gland. Methods: We retrospectively assessed patients from our tertiary hospital who underwent surgical treatment for masses in adrenal gland topography between 2006 and 2018. All patients had hormonal evaluations, according to the European and American Societies of Endocrinology guidelines. Two expert radiologists reviewed all images. Forty-six patients were included in the study, and the surgical specimens were analyzed by the same experienced pathologist. Patients with confirmed adrenocortical carcinoma (ACC) were excluded from this cohort. Results: Thirty-two (69.6%) patients were female. The median age was 49.5 years old (range 18-82yo). Abdominal or lumbar pain was the most frequent reason for medical investigation (43.5%). Adrenal incidentalomas represented 38.4% of the cohort. None of these patients had any clinical signs of adrenal hyperfunction, nor hormonal alteration. Twenty-four patients (52.17%) presented a mass on the left side, and only two cases presented bilateral adrenal masses. The median size was 8.6cm (1.3-18cm). The mean of Hounsfield Units (HU) on a non-contrasted CT was 25HU (0-50HU). Several etiologies were found: 8 cases (18%) of ganglioneuroma; 6 cases (13,5%) of adrenal cysts; 4 cases (9%) of leiomyosarcoma and adrenal hemorrhage; 3 cases (6.5%) of infectious disease; 2 cases (4.5%) of lymphangioma, schwannoma, and sarcoma. We also found single cases of renal cell carcinoma, poorly differentiated small cell neuroendocrine carcinoma, hepatocellular carcinoma, high grade dedifferentiated liposarcoma, epithelioid neoplasia, epithelial neoplasia with neuroendocrine differentiation, malignant peripheral nerve sheath tumor of the adrenal gland, poorly differentiated neuroblastoma, high grade lymphoma, myelolipoma, acute splenitis, arteriovenous malformation, and prostate cancer metastasis. Discussion and Conclusion: Ganglioneuroma was the most frequent diagnosis in adrenal incidentalomas in our cohort. In general, these conventional radiological exams could not differentiate lesions originated in the adrenal glands from lesions of other origins. In this large cohort, we could identify non-adrenal origin in approximately 45% of the patients with masses in the adrenal topography.