What is adrenal medullary lipoma? Adrenal medullary lipoma is a nonfunctioning benign tumor that occurs in the adrenal gland and is histologically composed of mature adipose tissue and normal hematopoietic tissue. The vast majority occur in the adrenal medulla and rarely in tissues outside the adrenal glands. What are the clinical manifestations of adrenal medullary lipoma? Most of them are asymptomatic in the early stage. When they grow into huge tumors, they manifest as abdominal discomfort, abdominal pain, low back pain, masses, atypical symptoms and a long medical history of more than ten years. Few patients have hematuria and hypertension. In rare cases, the tumor may rupture and bleed into the retroperitoneum, producing shock or acute abdomen. What are the principles of treatment for adrenal medullary lipoma? For small tumors with no clinical symptoms found by chance, they can be observed temporarily and reviewed regularly later. For those with clinical symptoms or large tumors, surgery should be performed to remove the tumor. The surgical treatment of adrenal medullary lipoma is limited to simple resection of the tumor without radical resection and lymph node dissection, and without removing the adjacent kidney.