What are the other Names for this Condition? (Also known as/Synonyms)

• Adrenal Gland Myelolipoma

What is Myelolipoma of Adrenal Gland? (Definition/Background Information)

• A myelolipoma is a rare and benign tumor consisting of fat cells and hematopoietic tissue cells (cells that form various blood cells - RBC, WBC, platelets). The tumor name is a combination of the terms marrow (myelo-) and fat (or lipoma)
• A myelolipoma tumor is seen among a wide age range of adults and can occur at various locations in the body. But, the most common location is the adrenal gland. The adrenal gland is an endocrine gland located atop each kidney. It is responsible for producing vital hormones such as cortisol and aldosterone
• Myelolipoma of Adrenal Gland can be associated with certain abnormalities such as Cushing syndrome and congenital adrenal hyperplasia. However, the cause of tumor formation is unknown
• The signs and symptoms of Adrenal Gland Myelolipoma depend upon the size of the tumors. Large tumors may cause a mass effect with abdominal discomfort and pain. It may also rupture leading to serious complications
• Typically, a surgical excision and removal of Myelolipoma of Adrenal Gland may be undertaken for large tumors or those presenting significant symptoms. The prognosis of Myelolipoma of Adrenal Gland is generally excellent with its complete removal, since it is a benign tumor

Who gets Myelolipoma of Adrenal Gland? (Age and Sex Distribution)

• Myelolipomas of Adrenal Gland is a rare tumor that is mostly observed in middle-aged and older adults (age range 40-80 years)
• Both males and females are affected and no predilection is noted
• No specific ethnic or racial preference is seen

What are the Risk Factors for Myelolipoma of Adrenal Gland? (Predisposing Factors)

Currently, the following have been identified as risk factors for Myelolipoma of Adrenal Gland:

• Cushing syndrome
• Conn syndrome (primary hyperaldosteronism)
• Congenital adrenal hyperplasia

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Myelolipoma of Adrenal Gland? (Etiology)

• The exact cause and mechanism of Myelolipoma of Adrenal Gland formation is unknown
• They are known to occur against a background of endocrinal abnormalities such as Cushing syndrome, conn syndrome, and congenital adrenal hyperplasia

What are the Signs and Symptoms of Myelolipoma of Adrenal Gland?

The signs and symptoms of Myelolipoma of Adrenal Gland may include the following:

• Most tumors are small-sized and may not exhibit any signs and symptoms
• Presence of a slowly-enlarging painless mass may be noted
• Large tumors (size over 4 cm) can compress the surrounding structures or organs and give the sensation of an abdominal mass
• Abdominal pain and discomfort
• Bleeding can occur within large tumors; hemorrhage within the tumors can lead to tissue death (or infarction)
• Signs and symptoms of any associated or underlying disorder may be noted

How is Myelolipoma of Adrenal Gland Diagnosed?

A diagnosis of Myelolipoma of Adrenal Gland may involve the following tests and procedures:

• Complete physical exam with evaluation of medical history
• Ultrasound scan of the abdomen: It is a noninvasive procedure that uses high frequency sound waves to produce real-time images
• Plain X-ray of the abdomen
• CT or CAT scan with contrast of the abdomen may show a tumor mass. This radiological procedure creates detailed 3-dimensional images of structures inside the body
• MRI scans of the abdomen: Magnetic resonance imaging (MRI) uses a magnetic field to create high-quality pictures of certain parts of the body, such as tissues, muscles, nerves, and bones. These high-quality pictures may reveal the presence of the tumor
• Vascular angiographic studies of the tumor
• Exploratory laparoscopy (diagnostic laparoscopy) may be required, if gastrointestinal symptoms are present. In this procedure, the abdomen is examined using a minimally-invasive technique, and a tissue biopsy and tissue for culture obtained

Although the above modalities can be used to make an initial diagnosis, a tissue biopsy of the tumor is necessary to make a definitive diagnosis to begin treatment. The tissue for diagnosis can be procured in multiple different ways which include: 

• Fine needle aspiration (FNA) biopsy of the tumor: A FNA biopsy may not be helpful, because one may not be able to visualize the different morphological areas of the tumor. Hence, a FNA biopsy as a diagnostic tool has certain limitations, and an open surgical biopsy is preferred
• Core biopsy of the tumor 
• Open biopsy of the tumor

Tissue biopsy:

• A tissue biopsy of the tumor is performed and sent to a laboratory for a pathological examination. A pathologist examines the biopsy under a microscope. After putting together clinical findings, special studies on tissues (if needed) and with microscope findings, the pathologist arrives at a definitive diagnosis. Examination of the biopsy under a microscope by a pathologist is considered to be gold standard in arriving at a conclusive diagnosis
• Biopsy specimens are studied initially using Hematoxylin and Eosin staining. The pathologist then decides on additional studies depending on the clinical situation
• Sometimes, the pathologist may perform special studies, which may include immunohistochemical stains, molecular testing, and very rarely, electron microscopic studies to assist in the diagnosis

A differential diagnosis, to eliminate other tumor types is considered, before arriving at a definitive diagnosis. The following tumors may be considered:

• Retroperitoneal liposarcoma
• Adrenocortical carcinoma
• Angiomyolipoma of kidney

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Myelolipoma of Adrenal Gland?

The complications of Myelolipoma of Adrenal Gland are dependent upon the size of the tumor and may include:

• Stress and anxiety due to fear of abdominal cancer
• Adrenal gland dysfunction due to large-sized tumors
• If bleeding occurs in large tumors (that are over 4 cm in size) suddenly, it can cause retroperitoneal hemorrhage, which can result in large blood loss leading to severe shock. This is a potentially life-threatening complication requiring emergency care. In this situation, the signs and symptoms could be nausea, vomiting, back pain, sudden drop in blood pressure, and palpitations. This clinical condition is termed Wunderlich syndrome
• Damage to the muscles, vital nerves, and blood vessels, during surgery
• Post-surgical infection at the wound site is a potential complication

Research has not conclusively proven that myelolipoma can turn malignant.

How is Myelolipoma of Adrenal Gland Treated?

The treatment measures for Myelolipoma of Adrenal Gland may include the following:

• Majority of asymptomatic tumors are not surgically removed: The healthcare provider may recommend a ‘wait and watch’ approach for small-sized tumors (not more than 4 cm in size) presenting mild signs and symptoms, after a diagnosis of myelolipoma is established
• Pain medications for tumors causing pain
• Replacement of hormones (to improve hormonal balance) in case of severe adrenal gland dysfunction
• Surgical intervention with complete excision (laparoscopic adrenalectomy, if required) can result in a complete cure; typically, tumors over 7 cm in size or greater are surgically removed
• Treatment of the underlying or associated endocrine conditions, if any
• Post-operative care is important: A minimum activity level is ensured, until the surgical wound heals
• Follow-up care with regular screening may be recommended by the healthcare provider

How can Myelolipoma of Adrenal Gland be Prevented?

• Current medical research has not established a method of preventing Myelolipoma of Adrenal Gland
• Regular medical screening at periodic intervals with tests and physical examinations are recommended

What is the Prognosis of Myelolipoma of Adrenal Gland? (Outcomes/Resolutions)

• The prognosis of Myelolipoma of Adrenal Gland depends upon the size of the tumor and severity of the signs and symptoms. It also depends upon the overall health of the individual, and its association with any endocrine disorders
• Typically, individuals with small-sized tumors have a better prognosis than those with larger-sized tumors (over 4 cm in size). In most cases, the prognosis of small-sized tumors is excellent with surgical intervention or appropriate treatment, since these are typically benign

Additional and Relevant Useful Information for Myelolipoma of Adrenal Gland:

Myelolipoma can occur at various locations in the body, such as the kidney, mediastinum, gastrointestinal tract, and liver.