Related narrative: Adrenal Myelolipoma
Adrenal myelolipomas are benign, non-functioning tumors of the adrenal cortex. They are uncommon, with a less than 1% incidence at autopsy. There is an equal male to female ratio and they are most commonly seen in individuals over 40. The most common presentation is an incidental adrenal mass. Myelolipomas are composed of mature adipose tissue with hematopoietic elements. The etiology is unknown, but theories include metaplasia of adrenal cortical or stromal cells under hormonal influence, emboli from bone marrow, or embryonic rests of hematapoietic tissue. These tumors have been found concurrently with other endocrinological disorders such as Cushing's syndrome, Conn's syndrome, Addison's disease, or congenital adrenal hyperplasia.
Symptoms from myelolipomas are usually related to mass effect or intratumoral hemorrhage. Hematuria, flank pain, palpable abdominal mass or hypertension may also be present. Myelolipomas are slow growing, usually not exceeding 5 cm in size. There have been giant forms reported with weights over 5 1/2 kilos. The treatment for larger (>4cm), symptomatic or rapidly growing tumors is surgery, which is usually curative. Smaller tumors may be observed with intermittent CT scans and biochemical analysis. There may be a role for fine needle aspiration (FNA) if the diagnosis is uncertain. The presence of megacaryocytes is the most important diagnostic feature, permitting the exclusion of malignancy.
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Retroperitoneal hemorrhage due to a ruptured adrenal myelolipoma. A case report.
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Evaluation of hormonal function in a series of incidentally discovered adrenal masses.