Overview
Acute mast cell leukemia (also called acute MCL) is a very rare and aggressive form of blood cancer. It belongs to a group of diseases called systemic mastocytosis, where a type of immune cell called a mast cell grows out of control. In acute mast cell leukemia, abnormal mast cells multiply rapidly in the bone marrow and spill into the bloodstream in large numbers — making up at least 20% of all cells in the blood. This is what makes it 'acute,' meaning it progresses quickly and is life-threatening. Mast cells normally help the body fight infections and respond to allergies. When they become cancerous, they release chemicals that cause widespread problems throughout the body. Patients often experience severe allergic-like reactions, skin changes, bone pain, and organ damage. The liver, spleen, and lymph nodes are commonly affected. Blood counts become abnormal, leading to anemia, bleeding problems, and increased infection risk. Treatment is very challenging. Options include chemotherapy, targeted therapy with drugs like midostaurin (Rydapt), and in some cases stem cell transplantation. Because this disease is so rare and aggressive, treatment is usually managed at specialized cancer centers. Outcomes remain poor overall, but research into new therapies is ongoing.
Also known as:
Key symptoms:
Extreme tiredness and weakness (anemia)Unexplained weight lossFever without infectionNight sweatsBone painEnlarged spleen causing abdominal discomfort or fullnessEnlarged liverSkin rash or hive-like spots (urticaria pigmentosa)Easy bruising or unusual bleedingFrequent infectionsSevere allergic-like reactions (flushing, low blood pressure, hives)Nausea, vomiting, or diarrheaSwollen lymph nodes
Sporadic
Usually appears on its own, not inherited from a parent
Adult
Begins in adulthood (age 18 or older)
FDA & Trial Timeline
4 eventsEssen Biotech — PHASE1, PHASE2
Kite, A Gilead Company — PHASE2
Nkarta, Inc. — PHASE1
University of Michigan Rogel Cancer Center — PHASE1, PHASE2
Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.
Treatments
No FDA-approved treatments are currently listed for Acute mast cell leukemia.
1 clinical trialare actively recruiting — trials can provide access to cutting-edge therapies.
View clinical trials →Rare Disease Specialist
Treatment Centers
8 centersBaylor College of Medicine Rare Disease Center ↗
Baylor College of Medicine
📍 Houston, TX
🏥 NORDStanford Medicine Rare Disease Center ↗
Stanford Medicine
📍 Stanford, CA
🔬 UDNNIH Clinical Center Undiagnosed Diseases Program ↗
National Institutes of Health
📍 Bethesda, MD
🔬 UDNUCLA UDN Clinical Site ↗
UCLA Health
📍 Los Angeles, CA
🔬 UDNBaylor College of Medicine UDN Clinical Site ↗
Baylor College of Medicine
📍 Houston, TX
🔬 UDNHarvard/MGH UDN Clinical Site ↗
Massachusetts General Hospital
📍 Boston, MA
🏥 NORDMayo Clinic Center for Individualized Medicine ↗
Mayo Clinic
📍 Rochester, MN
👤 Mayo Clinic Center for Individualized Medicine
🏥 NORDUCLA Rare Disease Day Program ↗
UCLA Health
📍 Los Angeles, CA
Travel Grants
No travel grants are currently matched to Acute mast cell leukemia.
Community
No community posts yet. Be the first to share your experience with Acute mast cell leukemia.
Start the conversation →Latest news about Acute mast cell leukemia
Disease timeline:
New recruiting trial: Feasibility and Safety of Collecting and Combining Autologous Hematopoietic Stem Cells With Chimeric Antigen Receptor (CAR) T-Cell Therapy in Subjects With Relapsed/Refractory Hematological Malignancies
A new clinical trial is recruiting patients for Acute mast cell leukemia
New recruiting trial: Local Manufacture of CAR T-Cell Products for the Treatment of B-Cell Lymphoma and B-Acute Lymphoblastic Leukemia
A new clinical trial is recruiting patients for Acute mast cell leukemia
New recruiting trial: CLIC-2201 for the Treatment of Relapsed/Refractory B Cell Malignancies
A new clinical trial is recruiting patients for Acute mast cell leukemia
New recruiting trial: CAR T Cells in the Treatment of Refractory and Relapsed CD19+ B Cell Neoplasms
A new clinical trial is recruiting patients for Acute mast cell leukemia
New recruiting trial: Fourth-gen CAR T Cells Targeting CD19/CD22 for Highly Resistant B-cell Lymphoma/Leukemia (PMBCL/CNS-BCL).
A new clinical trial is recruiting patients for Acute mast cell leukemia
New recruiting trial: A Study of MGD024 in Patients With Relapsed or Refractory Hematologic Malignancies
A new clinical trial is recruiting patients for Acute mast cell leukemia
New recruiting trial: (Apex) Bezuclastinib in Patients With Advanced Systemic Mastocytosis
A new clinical trial is recruiting patients for Acute mast cell leukemia
Caregiver Resources
NORD Caregiver Resources
Support, advocacy, and financial assistance for caregivers of rare disease patients.
Mental Health Support
Rare disease caregiving can be isolating. Connect with counseling and peer support.
Family & Caregiver Grants
Financial assistance programs specifically for caregivers of rare disease patients.
Social Security Disability
Learn how rare disease patients may qualify for SSDI/SSI benefits.
Questions for your doctor
Bring these to your next appointment
- Q1.Do I have the KIT D816V mutation, and how does that affect my treatment options?,Am I a candidate for stem cell transplantation, and what would that process involve?,Should I be treated with midostaurin or avapritinib, and what are the expected benefits and side effects?,Are there any clinical trials I might be eligible for?,How will we know if the treatment is working, and what happens if it stops working?,What emergency plan should I have at home in case of a severe allergic reaction?,Should I be referred to a specialized mastocytosis or bone marrow transplant center?
Common questions about Acute mast cell leukemia
What is Acute mast cell leukemia?
Acute mast cell leukemia (also called acute MCL) is a very rare and aggressive form of blood cancer. It belongs to a group of diseases called systemic mastocytosis, where a type of immune cell called a mast cell grows out of control. In acute mast cell leukemia, abnormal mast cells multiply rapidly in the bone marrow and spill into the bloodstream in large numbers — making up at least 20% of all cells in the blood. This is what makes it 'acute,' meaning it progresses quickly and is life-threatening. Mast cells normally help the body fight infections and respond to allergies. When they become
How is Acute mast cell leukemia inherited?
Acute mast cell leukemia follows a sporadic inheritance pattern. Genetic counseling can help families understand recurrence risk and testing options.
At what age does Acute mast cell leukemia typically begin?
Typical onset of Acute mast cell leukemia is adult. Age of onset can vary across affected individuals.
Are there clinical trials for Acute mast cell leukemia?
Yes — 1 recruiting clinical trial is currently listed for Acute mast cell leukemia on UniteRare. See the clinical trials section on this page for phase, sponsor, and site details sourced from ClinicalTrials.gov.
Which specialists treat Acute mast cell leukemia?
25 specialists and care centers treating Acute mast cell leukemia are listed on UniteRare, sourced from ClinicalTrials.gov principal investigators, published research, and the NPPES NPI registry.