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What is Systemic Mastocytosis?

Systemic mastocytosis is a rare disorder that happens when too many mast cells build up in parts of your body. Mast cells are a type of cell in your body’s connective tissue. These cells are part of your immune system and help fight disease and infection.

Systemic mastocytosis originates in the bone marrow, and can happen in the skin, liver, spleen, stomach, small intestine, or colon.

Systemic mastocytosis is considered a type of blood cancer with two main types.

Two Types of Systemic Mastocytosis

  1. Non-advanced systemic mastocytosis: This type includes indolent systemic mastocytosis (ISM) and smoldering systemic mastocytosis (SSM). This type is slow moving and in the early stages. Mast cells build up in the tissues and organs, but the buildup of cells does not cause problems in the organs.
  2. Advanced systemic mastocytosis (AdvSM): Mast cells build up in organs and tissues and cause problems in the organs they invade. ADvSM has three subtypes:
    1. Aggressive systemic mastocytosis (ASM)
    2. Systemic mastocytosis with associated hematologic neoplasm (SM-AHN)
    3. Mast cell leukemia (MCL)

Your doctor can answer any questions you may have about each type of systemic mastocytosis.

Common Signs & Symptoms of Systemic Mastocytosis

These are some common signs of systematic mastocytosis:

  • Allergic reaction that causes low blood pressure, hives, itching, flushed or pale skin, and swelling in the tongue or throat that can make it hard to breathe
  • Skin rashes, itching, hives, or flushing of the skin
  • Abdominal pain, diarrhea, nausea, or vomiting
  • Enlarged liver, spleen, or lymph nodes
  • Bone pain, and/or history of osteoporosis
  • Headaches, anxiety, brain fog
  • Anemia and bleeding disorders

Many other health problems can also cause these signs. If you have any of these signs, see your doctor as soon as possible.


Diagnosis of Systematic Mastocytosis

Doctors use these tests to diagnose systematic mastocytosis:

  • Physical exam and history: A health care provider examines your body for signs of disease. Your personal health habits, past illnesses, history of allergies to food or drugs, and symptoms of systemic mastocytosis guide the exam.
  • Laboratory tests: Your health care team tests your blood for evidence of mastocytosis and checks to see how well your organs are functioning.
  • Biopsies:
    1. Bone marrow biopsy: The health care provider removes a small sample of bone marrow to look for abnormal cells under a microscope.
    2. Biopsies of affected organs: The health care provider removes a small sample of the organs that may be affected by mastocytosis, such as skin, gastrointestinal tract, liver etc.
  • Imaging tests: Using CT scans, MRIs, and ultrasounds, your health care provider can create detailed images of internal organs.

Treatments for Systemic Mastocytosis

Huntsman Cancer Institute offers different types of treatment for systemic mastocytosis. The treatment each patient receives depends on the exact type of mastocytosis, the recommendations of the care team, and the patient’s goals of therapy.

These are the most common types of treatment:

  • Watchful waiting
  • Histamine blockers and mast cell stabilizers
  • Chemotherapy
  • Targeted therapy
  • Stem cell transplant
  • Bisphosphonate Therapy
  • Participation in Clinical Trials

Risk Factors

Anything that increases your chance of getting a disease is called a risk factor. Having a risk factor does not mean you are sure to get the disease. It means your chances are higher than the average person’s. Talk with your doctor to learn more about your risk.

Most cases of systemic mastocytosis are not hereditary, but it can sometimes be found within families.

Learn more about ways to prevent cancer and about family history and genetic counseling.

Our Experts

At Huntsman Cancer Institute, a team of experts work together to care for you. Our specialists review each patient’s case, coordinate treatment, and plan follow-up care. The Mastocytosis Program at Huntsman Cancer Institute has been designated as a Center of Excellence by the American Initiative in Mast Cell Diseases (AIM).

Your care team may include these specialists:

  • Hematologists (Blood specialist doctors), pain and palliative care doctors, dermatologists, and doctors from other specialties, as needed
  • Diagnostic specialists such as radiologists and pathologists
  • Pharmacists and nurses
  • Dietitians and social workers
  • Geneticists

Our care teams may also include advanced care nurses, and physician assistants. Everyone on your care team talks with each other to plan and give treatment. They can talk to you about any questions or concerns you have about systemic mastocytosis.

Find a Systemic Mastocytosis Doctor

Clinical Trials

For more information about available clinical trials, please call 801-587-4427.

Contact Us

Feel free to contact us with any questions or advice:

  • Physicians – Contact us for new patient referrals for advice on evaluating or managing systemic mastocytosis
  • Patients – Contact us for information about systemic mastocytosis and treatment recommendations or information about our multidisciplinary program approach
  • Others – Contact us for any information about systemic mastocytosis

For more information, please call:

Patient Coordinator


Clinical Trials