Myelolipoma are extremely rare, non-cancerous tumors. These masses have been found most often in the adrenal glands. Other common locations for these growths are the liver, lungs, and renal sinuses. This type of growth is almost always asymptomatic and is often discovered while investigating a separate medical problem. Usually this type of tumor does not require treatment. If the mass becomes extremely large or impacts the surrounding tissue, it may be surgically removed.
These benign adrenal lesions are composed of adipose, or fat tissue, and hemopoietic cells, or cells that produce red and white blood cells and platelets. It is unknown what causes these tumors. Due to the rare nature of the growths, research into a cause is difficult to conduct.
Myelolipoma tumors are typically asymptomatic and are discovered only during a computerized tomography scan for a separate issue or during an autopsy. When symptoms are reported, they typically involve abdominal or back pain. Adrenal myelolipoma are most often found later in life, between the ages of 50 and 70. The tumors are fairly small, typically measuring less than 1.6 inches (4 cm). Medical conditions that often present with this type of tumor include hypertension, obesity, and type 2 diabetes.
A hepatic myelolipoma, a benign tumor, is typically found for unknown reasons on the right liver. These lesions are usually much bigger than the adrenal gland version, often reaching sizes of 4 inches (10 cm). Again, this type of tumor is most often asymptomatic and is discovered during a routine examine or during a scan to investigate a different medical problem. The presence of this type of growth in the lung and renal sinuses is extremely rare but is occasionally reported.
The treatment for myelolipoma tumors is to biopsy the mass to confirm that it is benign and then to monitor the growth of the mass and chronicle its impact on the surrounding tissue. If the mass changes in size quickly, surgery is sometimes recommended to check the pathology and confirm that the growth is in fact benign. Surgery may also be performed when the size of the tumor impacts surrounding tissue or organ function. Although this type of tumor is extremely rare, it has been found more often in patients who are afflicted with endocrine or hormonal medical conditions such as Cushing’s disease and Conn’s syndrome. Use of steroids or having a disease that causes a natural increase in cortisol levels such as obesity, hypertension, and diabetes may also increase the chances of developing one of these growths.