Systemic mastocytosis is a rare blood cancer in which abnormal mast cells (a type of white blood cell) build up in your skin and other organs. You might get a variety of symptoms, including itchy skin, a bellyache, rapid heartbeat, lightheadedness, anemia, and other problems. There's no cure, but treatments can help you manage the condition.
Mast cell disorders
These are conditions in which mast cell function leads to various symptoms. Mast cells are part of your immune system. They help fight off illness, play a role in allergic reactions, and heal wounds.
Systemic mastocytosis is a type of mast cell disorder. In it, extra abnormal mast cells gather in different parts of your body, such as your skin, bone marrow, bones, and digestive tract.
Certain triggers set off these mast cells and lead them to release chemicals. For example, your body may release histamines, which cause flushing of your face, neck, and chest, along with itching, hives, and other symptoms.
If you have a serious episode, systemic mastocytosis can affect how your organs work. In some cases, mast cells may cause an allergic reaction called anaphylaxis, which can be life-threatening. If that happens to you, you'll need to get medical help right away and use an epinephrine auto-injector.
Consider reaching out to family and friends for support as you manage this disease. They can help you deal with the emotions and stress that come with the challenges of a long-term condition like systemic mastocytosis.
Systemic Mastocytosis Causes
Systemic mastocytosis doesn't usually run in families. A random change (mutation) in the KIT gene shows up in mast cells in people with systemic mastocytosis. This gene helps program a protein that's in charge of how cells grow. It also plays a role in the way mast cells develop and survive.
Signs of systemic mastocytosis can show up at any age, but it usually happens when you're an adult. You're most likely to get a diagnosis when you're in your 40s or 50s.
If you have systemic mastocytosis, certain triggers cause mast cells to send out chemicals and cause symptoms. They aren't the same for everyone, but common triggers include:
- Alcohol
- Spicy foods
- Changes in temperature
- Insect stings
- Stress or anxiety
- Surgery
- Vaccines
- Certain medicines, such as aspirin, opioids, and nonsteroidal anti-inflammatory drugs (NSAIDs)
It's also possible to get symptoms without any triggers.
Symptoms of Systemic Mastocytosis
How you feel may depend on the type of systemic mastocytosis you have and where mast cells have built up in your body. Symptoms include:
- Itching, flushing, or hives
- Stomach pain or diarrhea
- Feeling sick or throwing up
- Pain in your bones or muscles
- Anemia or bleeding disorders
- Depression, anxiety, or mood changes
- Trouble concentrating
- Swollen lymph nodes, liver, or spleen
- Headache
- Lightheadedness or fainting
Types of Systemic Mastocytosis
There are five main types of systemic mastocytosis. They vary in how serious they are and what symptoms they cause.
Indolent systemic mastocytosis (ISM)
Indolent systemic mastocytosis (ISM) is the most common and least serious type. You'll likely have skin symptoms. Your liver, spleen, and digestive tract may also be affected. Symptoms are usually mild and develop over several years. As your abnormal mast cells increase, your condition may get worse over time. But the risk of progression to more severe types is low.
Smoldering systemic mastocytosis
Smoldering systemic mastocytosis has milder symptoms than ISM. But more abnormal mast cells grow in your liver and spleen, which can cause those organs to become enlarged. There's a greater risk of progression to a more severe disease.
Systemic mastocytosis with an associated hematologic nonmast cell lineage disorder (SH-AHNMD)
In this case, you have another blood or bone marrow disorder along with your systemic mastocytosis. Blood disorders include myeloproliferative neoplasms and myelodysplastic syndrome. This type is serious. It impacts your organs.
Aggressive systemic mastocytosis (ASM)
Abnormal mast cells can grow into your bones in this rare, severe type of mastocytosis. That weakens your bones and makes them likely to break. You'll have major symptoms, including organ dysfunction and damage.
Mast cell leukemia (MCL)
In some rare cases, systemic mastocytosis can turn into mast cell leukemia. This type is very rare and aggressive.
Getting a Diagnosis
Your doctor will ask about your health history and do a physical exam. Based on your symptoms, you may need more testing.
Questions for Your Doctor
It helps to write down a list of questions and take it with you to your doctor's appointment. Some questions you might want to ask are:
Systemic Mastocytosis Treatment
Your doctor will decide your treatment plan based on your symptoms, the organ that's affected, and the kind of systemic mastocytosis you have.
Medications for systemic mastocytosis symptoms
The treatments may include:
Antihistamines. These drugs may relieve skin reactions, such as flushing and itching, and digestive system symptoms.
Epinephrine. This hormone treats anaphylaxis. You should always carry this with you. Your doctor can teach you how to give it to yourself.
Proton pump inhibitors. These medicines curb stomach acid, which may ease digestion problems.
Mast cell stabilizers. These drugs, such as cromolyn sodium and ketotifen, block mast cells from releasing histamines.
Bisphosphonates. These – which can be taken by mouth or via IV – can help manage bone pain and osteoporosis.
Monoclonal antibodies. Doctors may use monoclonal antibodies such as omalizumab (Xolair) as an "off-label" treatment for systemic mastocytosis symptoms.
Steroids. They may help with skin, nasal, and respiratory symptoms and can be part of your treatment if you get anaphylaxis.
Other systemic mastocytosis treatments
You may get other treatments for systemic mastocytosis, including:
Targeted therapy. These drugs target a specific gene, protein, or tissue involved in the disease. For systemic mastocytosis, your doctor may suggest a tyrosine kinase inhibitor to block specific signaling proteins that cause cancer to grow and spread. You may need this kind of treatment if you have serious or life-threatening symptoms.
Chemotherapy. You may need this treatment if your systemic mastocytosis is fast-moving and you have significant damage to your organs. You take these drugs through an IV or by mouth. They kill cancer cells throughout your body.
Stem cell transplant or bone marrow transplant. In rare cases, your doctor may consider this treatment. During this surgery, your bone marrow cells are replaced with healthy bone marrow or stem cells. Doctors usually only recommend this for the most aggressive forms of systemic mastocytosis.
How to manage your triggers
You should steer clear of things that trigger you whenever possible – whether it's food, temperature, insects, fumes, stress, or something else in your environment.
"The easiest treatment is just to avoid," says hematologist Paul Hendrie, MD, PhD, of Fred Hutchinson Cancer Center and the University of Washington in Seattle.
That could mean small or major adjustments to your everyday life.
"It can be life-changing and occupation-changing," Hendrie says.
Manage your surroundings, including at work. For example, if fragrances trigger your symptoms, request that perfumes, air fresheners, or candles be removed from your workplace.
Some people are very aware of what triggers them, while others need to investigate.
Keep a record of when you have symptoms and what you've eaten or been exposed to beforehand to help determine your triggers.
Clinical trials for systemic mastocytosis
Clinical trials are how new treatments are developed for all kinds of conditions, including systemic mastocytosis. They help researchers learn more about conditions and treatments. Clinical trials also give you a chance to benefit from new treatments.
Ask your doctor about clinical trials that could be a fit for your symptoms and type of mastocytosis. Drugs in clinical trials may work as well as, or better than, approved medications and have fewer side effects, Hendrie says.
To find current trials, search ClinicalTrials.gov, a database managed by the National Library of Medicine.
Complications of Systemic Mastocytosis
Some complications of systemic mastocytosis include:
Anaphylaxis. This is a serious allergic reaction with symptoms like a rapid heartbeat, fainting, and shock. You may need a shot of epinephrine.
Blood disorders. People with systemic mastocytosis can develop anemia and poor blood clotting.
Osteoporosis and osteopenia. Systemic mastocytosis impacts your bones and bone marrow.
Organ failure. Too many mast cells in your organs can cause inflammation and damage.
Peptic ulcer disease. Frequent stomach irritation can cause ulcers in your digestive tract.
The right treatment can help you avoid and lessen complications. Your doctor will monitor you regularly, using blood and urine samples and bone density tests.
Taking Care of Yourself
When you have systemic mastocytosis, it's important to take care of yourself and be proactive.
"I tell people to be proactive about their diagnosis," Hendrie says. "People should be proactive about their medical care, both routine and emergency."
Make sure all your doctors and care providers know about your systemic mastocytosis — especially if you may be having surgery — since your anesthesia drugs could be affected.
"Patients should avoid triggers where they can and be prepared to deal with events when they happen," Hendrie says.
Here are some tips.
What to Expect
How your disease develops depends a lot on the type of systemic mastocytosis you have. ISM, for instance, is the mildest kind. Your symptoms may slowly get worse.
The more serious types, such as ASM and MCL, move more rapidly. For ASM, you may need treatment for problems such as bone loss. If you have MCL, which is a rare type, you may get blood disorders, including leukemia.
Whatever type you have, after your diagnosis, you'll go to regular follow-up appointments with your doctor. They'll track your disease and check that your treatments are working.
Getting Support
When you're managing a condition like systemic mastocytosis, you may sometimes feel like you're on an emotional roller coaster. If that's the case with you, it's OK to look beyond your circle of family and friends to get the backing you need.
A support group can be a huge help, as you'll get to talk to other people who understand what you're going through. These groups meet in person, on the telephone, or online.
To find a group, you can ask your doctor, social worker, or other people with systemic mastocytosis. Or you can go to the websites of The Mastocytosis Society, RareConnect, and Mast Cell Action.
Caring for your mental and emotional health
If you find that the challenges of managing your disease are making you depressed or anxious, talk to your doctor. They can put you in touch with mental health professionals who are experts in treating these problems.
Systemic mastocytosis can affect you emotionally and sometimes cognitively, causing mental fogginess, Hendrie says. Some treatments can have similar side effects.
"Even if it's related to your mastocytosis, that doesn't mean that you shouldn't try to address it," he says. "Different people respond to different modalities of treatment."
Individual counseling with a therapist or talking to a support group could help. Try meditation. Regular walking or other exercise might make you feel better. And medication can help with severe depression or anxiety.
Takeaways
Living with systemic mastocytosis will require changes. Knowing and avoiding your triggers and finding the right medication will make things easier and your symptoms more manageable. Your doctor will help you develop a plan and monitor your condition. Be prepared. Always carry an epinephrine auto-injector.
Systemic Mastocytosis FAQs
Here are some frequently asked questions about systemic mastocytosis.
What are some common triggers for systemic mastocytosis symptoms?
They vary from person to person. But they may include alcohol, insect stings, changes in temperature, spicy food, stress, and some meds.
Will systemic mastocytosis shorten my life?
It depends on the type of systemic mastocytosis you have. The most common and milder type, ISM, typically doesn't affect how long you'll live. But more aggressive types, such as ASM, can shorten your life expectancy. Proper treatment makes a difference. Talk to your doctor and follow their guidance.
Is there a cure for systemic mastocytosis?
Some rare types of systemic mastocytosis can be cured with a stem cell transplant. But there's no known cure for most types. There are treatments and lifestyle choices that may help you manage symptoms and complications.
Who gets systemic mastocytosis?
You can start to have symptoms of systemic mastocytosis at any age, but it usually happens after adolescence.
This condition is rare. It affects about 13 of every 100,000 people. It's usually not inherited but is caused by a mutation in your cells after conception.
What else can be mistaken for systemic mastocytosis?
Similar symptoms come from many other disorders, including:
- Carcinoid syndrome, a rare condition linked to neuroendocrine tumors
- Vipoma or gastrinoma, types of endocrine tumors in your pancreas
- Chronic urticaria, hives that come back and last a long time
