Myelodysplastic neoplasms
MDS with biallelic TP53 inactivation (multi-hit TP53)
Also called Myelodysplastic neoplasm with biallelic TP53 inactivation
If you or someone you love has just heard this diagnosis, start here. This guide explains what the condition is, how it is usually treated and where a transplant fits.
MDS with biallelic TP53 inactivation is a high-risk myelodysplastic neoplasm in which both copies of an important tumor-suppressor gene are affected. Donor transplantation may offer a chance of lasting disease control, but relapse remains a major concern.
Other names and abbreviations
MDS-biTP53, MDS with multi-hit TP53, myelodysplastic syndrome, MDS, MDS with mutated TP53, MDS/AML with mutated TP53, MDS with biallelic TP53 alteration, multi-hit TP53-mutated MDS
In short
- This is a high-risk type of MDS, a marrow cancer. Both copies of TP53, a gene that helps stop damaged cells from dividing, are affected.
- Treatment may include azacitidine or decitabine, supportive care and clinical trials. But the disease can be hard to control, and responses may not last.
- For some people, a donor stem cell transplant may offer lasting control. Even so, the chance of the disease coming back remains a major concern.
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Underlined words open a short explanation. See all terms
Where transplant fits
Allogeneic transplantationComing from another person. In an allogeneic, or donor, transplant, the stem cells come from a relative or an unrelated volunteer whose cells are a close enough match to the patient's. may offer lasting control for selected patients, but relapseWhen a disease comes back after a period of getting better. Relapsed disease has returned after treatment helped for a time. remains a major concern. Post-transplantA treatment that gives a patient healthy blood-forming stem cells through a vein. The cells travel to the bone marrow and replace faulty marrow or marrow damaged by treatment. They can come from the patient or a donor. medicines and other interventions are individualized; no preventive regimen is universally established for this subtype.
Treatment depends on the exact diagnosis, disease stage, prior treatment and the person’s health.
Some patients need a donor who is not a relative.
See if you can joinKey facts
- Who it affects
- This MDS subtype mainly affects adults and is also seen after prior cytotoxic therapy; a prior treatment history is not required for diagnosis.
- How common
- TP53 changes are found in about 7 to 11 in 100 people with MDS; about two-thirds of them have the multi-hit formPeople with MDS in published studies summarized in the WHO 5th-edition classification, 2022 Source: How common
- Cells used in a transplant
- Donated blood-forming cells for allogeneic transplantation. Marrow, peripheral blood or cord blood and donor type are selected for the patient and transplant approach.
- Where a donor fits
- Donor transplant option
The condition
What it is
Myelodysplastic neoplasmsA group of cancers in which the bone marrow does not make enough healthy blood cells and abnormal cells appear in the blood or marrow. Also called myelodysplastic syndromes (MDS). Sometimes they turn into acute myeloid leukemia., also called myelodysplastic syndromes (MDS), are cancers of blood-forming stem cellsYoung cells that can grow into every type of blood cell: red cells that carry oxygen, white cells that fight infection and platelets that help blood clot. They are found in the bone marrow and the bloodstream.. Abnormal development means the marrowThe soft, spongy tissue in the center of most bones. Red bone marrow holds the blood-forming stem cells that make red blood cells, white blood cells and platelets. does not reliably produce enough working blood cells. MDS can cause serious problems without ever progressing to acute myeloidHaving to do with the bone marrow, or with certain blood-forming cells made there. Also called myelogenous. Acute myeloid leukemia (AML) is a fast-growing cancer that starts in these cells. leukemia (AML).
TP53 helps prevent damaged cells from continuing to divide. “Biallelic” means that both copies in the abnormal clone are inactivated, through mutations and/or loss of normal gene material. This is more specific than finding any TP53 mutation. In the WHO classification, this category takes priority over some other genetically defined MDS names.
Marked as affected: blood stem cells, red blood cells, platelets and granulocytes.
- Blood stem cell, Affected, In the bone marrow
- Myeloid line
- Red blood cells, Affected
- Platelets, Affected
- Granulocytes, Affected
- Monocytes
- Lymphoid line
- B cells
- Plasma cells, Develop from B cells
- T cells
- NK cells, Natural killer cells
- Myeloid line
What causes it
MDS usually develops through acquired genetic changes in blood-forming cells, and the underlying cause is often unknown. Age, previous chemotherapy or radiation, smoking and some chemical exposures can increase risk.
Inherited predisposition can contribute in a minority of patients. Personal and family history may prompt genetic evaluation, which can also affect the suitability of related donors. MDS is not contagious.
Symptoms and effects
Anemia can cause fatigue, breathlessness or difficulty with ordinary activities. Low neutrophilsA type of white blood cell that is one of the first to respond to germs such as bacteria. Low neutrophil levels raise the risk of serious infection. increase infection risk, and low plateletsTiny pieces of cells in the blood that help form clots to slow or stop bleeding. They are made in the bone marrow. Too few platelets can cause easy bruising and bleeding. can cause bruising or bleeding. Some people first learn about MDS through a routine blood test.
Blood counts, marrow findings and molecular tests help track the disease. The subtype name and the overall risk score answer different questions: prognosis depends on the combination of genetic findings, blast countYoung blood cells that have not finished developing. In leukemia and some related diseases, abnormal blasts build up in the marrow and blood and leave less room for healthy blood cells. Doctors count blasts to help identify the disease. and blood-cell shortages, not a single label.
Biallelic TP53 abnormalities are associated with an aggressive course and a higher risk of relapse, including after transplantation. These population-level findings guide careful planning; they cannot predict an individual’s course with certainty.
Diagnosis and treatment
How MDS with multi-hit TP53 is diagnosed
Like other MDS, it starts with blood tests. A complete blood count (CBC) and a blood smear show low counts and changes in the size and shape of cells. Blood tests also check vitamin B12 and folate levels, which are usually normal in MDS. A bone marrow test (aspiration and biopsy), from the hipbone or breastbone, shows the share of immature cells (blasts) and abnormal-looking cells. For this diagnosis, blasts must be under 20%.
The key step is genetic testing of blood or marrow. Gene sequencing (next-generation sequencing) looks for TP53 changes in the main parts of the gene. Chromosome tests, often a probe test called FISH or an array test, look for loss of the part of chromosome 17 that holds TP53. The diagnosis needs two or more TP53 changes, or one change plus loss of the other copy. More than 9 in 10 people with this type also have many chromosome changes (a complex karyotype).
A pathologist typically sends a biopsy report within about 10 days, and some test results may come in separate reports. If one TP53 change shows up at a high level, the team first rules out a change the person was born with before counting it as a sign that both copies are affected. When an inherited cause is suspected, the WHO says genetic counseling and a family history are part of the workup.
Another naming system, the International Consensus Classification, groups these cases a little differently, as MDS or MDS/AML with mutated TP53.
How it is treated
Treatment may use hypomethylating medicines such as azacitidine or decitabine, supportive care and clinical trialsA research study that tests how well a new medical approach works in people. Trials can test new ways to screen for, prevent, diagnose or treat a disease.. A response can improve blood counts or reduce disease, but controlling the clone can be difficult and responses may not last.
Allogeneic transplantation remains a potentially curative option for selected patients. Assessment considers disease burden and response, other genetic findings, fitness, available donors and what matters to the patient. High relapse risk is part of informed decision-making, not an automatic reason to exclude someone.
After transplant, monitoring may lead to changes in immunosuppressionTreatment that lowers the activity of the immune system. It can calm an immune attack on the body, as in aplastic anemia, or help keep the body from rejecting a transplant. It also makes infections harder to fight., donor lymphocyte treatmentWhite blood cells (lymphocytes) from the same donor, given some time after a donor transplant. They may kill cancer cells that are left. It is used for some cancers, such as chronic myeloid leukemia (CML) that has come back. or drug therapy in selected circumstances. Preventive drug treatment is being studied; a specific maintenance regimen is not universally proven or required for every person with TP53-altered MDS. Clinical trials are especially relevant.
Kinds of treatment described for MDS with biallelic TP53 inactivation (multi-hit TP53): supportive care, medicines, a donor stem cell transplant (for some people) and clinical trials.
After diagnosis, the options described here
Supportive care
Supportive care helps with the effects of low blood counts.
Medicines
Azacitidine or decitabine can improve blood counts or reduce disease, but responses may not last.
Donor stem cell transplant, For some people
For some people, a donor stem cell transplant may offer lasting control, though the chance of the disease coming back remains a concern.
What a transplant involvesClinical trials
Clinical trials are especially relevant for this type of MDS.
These are the kinds of treatment this page describes, not a plan. Which ones fit, in what order and whether they are combined differs from person to person.
When transplant specialists are usually consulted
NMDP and ASTCT guidance recommends high-resolution HLA typingA lab test that finds a person's tissue type (HLA markers). It starts with a blood draw or a cheek swab. Doctors compare a patient's results with those of relatives, registry donors and cord blood units. at diagnosis for MDS with a high IPSS-R score or adverse chromosome or gene features. Most people with this type qualify: the WHO notes that more than 9 in 10 have a complex karyotype and so are very high risk on the IPSS-R. Early typing lets testing of relatives and a donor search start sooner.
Read the guidanceWhat a transplant involves
- Step 1
: Finding a donor
Relatives are tested first to see whether their tissue type (HLA) matches. If none match, the team searches donor registries and cord blood banks.
- Step 2
: Conditioning
Chemotherapy, sometimes with radiation, prepares the body for the new cells.
- Step 3
: Transplant day, Day 0
The donor’s cells are given through a vein, like a transfusion.
- Step 4
: Engraftment
The new cells settle in the marrow and start making blood cells, usually within weeks.
- Step 5
: Recovery
The immune system rebuilds over months. The team watches for infection, graft-versus-host disease (donor immune cells attacking the body) and relapse.
Daily life and the donor’s role
Living with the condition and treatment
Repeated blood tests, clinic visits and sometimes marrow samples are part of care. Some people need regular transfusionsPutting blood, or parts of blood such as red cells or platelets, into a person's bloodstream through a vein. Some people with blood disorders need regular transfusions. or medicines to support blood production. The practical burden depends on the degree of anemia, infection risk, treatment schedule and other health conditions.
If transplant is considered, discussions include the chance of disease control, treatment-related risks, recovery support and personal goals. A donor search can take place while these decisions and other treatment continue.
The role of a blood stem cell donor
A donor can make a transplant possible, but a good match does not remove the high risk that comes with this subtype. Transplant plans take into account both the risks of the transplant itself and the chance that the disease comes back.
When allogeneic transplantation is selected, the graftThe blood-forming stem cells given to a patient in a transplant. In a donor transplant, the graft comes from the donor's bone marrow or blood, or from donated cord blood. comes from another person. A matched relative, an unrelated registry donor, a half-matchedHalf-matched. A haploidentical donor's tissue type (HLA) matches about half of the patient's. It may be a parent, child, brother or sister. Care teams may use one when a fully or closely matched donor is not available. relative or donated cord bloodBlood collected from a newborn baby's umbilical cord after birth. It contains many blood-forming stem cells, so donated cord blood can be used for a stem cell transplant. may be suitable. HLA compatibilityMarkers on most cells that make up a person's tissue type. Doctors test a patient's and donor's HLA to see how well they match. The more markers they share, the better the chance the body accepts the donor's cells., donor age and availability, patient health and the transplant approach all matter; no donor category is best for every person.
Highlighted here: a relative, an unrelated volunteer and donated cord blood.
The person’s own cells
Autologous transplant, no donor
Collected from the person before treatment, then given back.
A relative
Donor transplant (allogeneic)
A brother or sister may be a full match. Parents and children can be half-matched donors.
An unrelated volunteer
Donor transplant (allogeneic)
Found through a donor registry.
Donated cord blood
Donor transplant (allogeneic)
Collected from a baby’s umbilical cord after birth and stored in a public bank.
Some patients rely on a volunteer donor they have never met. Joining your country’s registry could make you that person for someone.
Join the registryFinding a donor and the outlook
How a donor is found
When a transplant from a donor is planned, the team usually tests brothers and sisters first. Each full sibling has about a one in four chance of being a full match.
Most patients do not have a matched relative. In the words of NMDP, the U.S. registry, “75% of patients don’t have a fully matched donor in their own family.” The team then searches registries of volunteer donors around the world and banks of donated cord blood. In some transplants, a half-matched parent, child or sibling can also be the donor.
8 of 8
All eight markers match. Doctors call this a full match.
8 of 8: the donor matches the patient at all eight markers, two each for HLA-A, HLA-B, HLA-C and HLA-DRB1.
7 of 8
One marker differs. Some transplants use a donor like this.
7 of 8: the donor matches at seven of the eight markers. One HLA-C marker differs.
Half-matched
One set, inherited together from one parent, matches. The rest may or may not.
Half-matched: the donor matches the four markers the patient inherited from one parent. The other four may or may not match.
- Matches
- Differs
- May or may not match
- Top row: from one parent. Bottom row: from the other.
- DR means HLA-DRB1
Doctors can look at up to 12 HLA markers, and usually aim to match 8 to 10 of them. This drawing shows the 8 that transplant guidelines count, and it reads each one as simply matching or not.
Matching depends on inherited tissue markers called HLA, so a patient is most likely to match someone who shares their ancestry. Every person who joins makes the search a little more likely to succeed, especially for patients from groups that are underrepresented on registries.
Looking ahead
Outlook for MDS with multi-hit TP53
This is one of the hardest types of MDS to treat. With both copies of TP53 affected, the abnormal cells tend to gather many chromosome changes. The disease is more likely to progress to acute myeloid leukemia (AML), and responses to azacitidine or decitabine are often short-lived. In a large international study, multi-hit TP53 predicted shorter survival even after other risk factors were counted.
A donor transplant is still the only treatment with a chance of lasting control. In a U.S. trial of people aged 50 to 75 with higher-risk MDS, people with a TP53 change who had a transplant were more likely to be alive 3 years later than those who did not. But relapse after transplant is common. A review that pooled eight studies of TP53-changed MDS found relapse in about 59 in 100 people after transplant. Clinical trials are an important option, before or after transplant.
These numbers are hard to read. They describe groups, not any one person. In the same review, about a third of people in the studies that reported it were alive without the disease getting worse 4 years after transplant. A care team can explain what the full set of results means in each case.
About these numbers. Each one says which group of people it comes from, and the place and years where the source gives them. It describes what happened across that group, not what will happen to any one person. And a figure measured among people who had a transplant is not the same as the number of people who need one.
- 8.7 months (2.5 years with a single TP53 change; 3.5 years with no TP53 change)Median survival, multi-hit TP53
253 people with multi-hit TP53 among 3,324 people with MDS or closely related conditions, tested at or near diagnosis before treatment, from 24 centers (International Working Group for Prognosis in MDS); published 2020
Read the source: Median survival, multi-hit TP53 - 20%Alive 3 years after joining the trial, multi-hit TP53
48 people aged 50 to 75 with higher-risk de novo MDS and multi-hit TP53 in the U.S. BMT CTN 1102 trial (enrolled 2014 to 2018); includes people who did and did not have a transplant; published 2023
Read the source: Alive 3 years after joining the trial, multi-hit TP53 - 23% vs 11%Alive at 3 years with any TP53 change: transplant vs no transplant
87 people aged 50 to 75 with higher-risk de novo MDS and a TP53 change in the same U.S. trial (enrolled 2014 to 2018); transplant counted from the time it happened; published 2023
Read the source: Alive at 3 years with any TP53 change: transplant vs no transplant
Median means half the group lived longer and half lived less long. Transplant figures describe people well enough to have one, not everyone with this type of MDS.
Common questions
What does multi-hit or biallelic TP53 mean in MDS?
TP53 is a gene that helps stop damaged cells from dividing. Each cell has two copies. In this type of MDS, both copies in the abnormal blood cells are damaged, through two or more changes (mutations) or one change plus loss of the other copy. That leaves those cells with no working p53 protein. Multi-hit and biallelic mean the same thing here. Since 2022, the WHO has named this a separate type of MDS because it behaves differently from MDS with a single TP53 change.
What is the life expectancy for MDS with a TP53 mutation?
It depends a lot on whether one or both copies are affected. In a large international study published in 2020, people with multi-hit TP53 had much shorter survival than people with a single TP53 change or none. The outlook section on this page gives the figures. They come from people tested before treatment. They cannot predict one person's course, and transplant can change the picture for some people.
Can a stem cell transplant cure TP53-mutated MDS?
It can for some people, but it is harder than in other types of MDS. A donor transplant (allogeneic transplant) is the only treatment with a chance of cure. A U.S. trial studied people aged 50 to 75 with higher-risk MDS and a TP53 change. More of those who had a transplant were alive at 3 years than those who did not. The outlook section on this page gives the figures. Relapse after transplant is common, and ways to lower that risk are being studied in clinical trials.
Is TP53-mutated MDS inherited?
Usually not. In MDS, TP53 changes are usually picked up during life in the abnormal blood-forming cells only. Rarely, a person is born with a TP53 change. This causes Li-Fraumeni syndrome, a rare condition that raises the risk of several cancers, including leukemias. The WHO lists it among inherited conditions that can lead to myeloid blood cancers such as MDS. An inherited cause also matters when choosing a related donor, because a relative may carry the same change.
Is a single TP53 mutation the same as multi-hit TP53?
No. The WHO separates one TP53 change from two or more hits. In a large international study, people with a single TP53 change, where the other copy still works, did about as well as people without TP53 changes. Multi-hit TP53 was linked with much shorter survival. In a U.S. trial limited to higher-risk MDS, though, survival at 3 years was similar for single and multi-hit TP53. So blast count, chromosome results and other findings still matter.
For your next appointment
MDS with biallelic TP53 inactivation (multi-hit TP53)
From the Jada Bascom Foundation disease library, jadabascomfoundation.org. Printed .
Questions to bring to your care team
- How many TP53 changes were found, and was loss of chromosome 17p (or of the other TP53 copy) checked?
- Could any of my TP53 change be inherited, and does that affect testing my relatives as donors?
- Is there a clinical trial for TP53-altered MDS that fits me, before or after transplant?
- If I have a transplant, how will you watch for relapse, and what would you do if early signs appear?
- What is the exact name of the diagnosis or subtype, and what does it mean for treatment?
- What is the goal of each treatment you are suggesting?
- Is a transplant being considered? Why now, or why not yet?
- Should brothers and sisters have HLA typing, and when does a donor search start?
- What happens if a fully matched donor is not found?
- Where can our family find support during treatment?
A one-page list to take to the next appointment, with room for notes.
Supporting someone with a diagnosisSupport for patients and families
These independent organizations offer information and support. JBF is not affiliated with them.
- MDS Foundation A global nonprofit offering MDS education, patient guides, patient forums and ways to connect with experts and other patients.Worldwide
- Aplastic Anemia and MDS International Foundation (AAMDSIF) Offers patient guides, a helpline, virtual support groups and a peer support network for people with MDS and related bone marrow diseases.United States
- MDS UK Patient Support Group A UK charity offering free membership, trusted information, online support meetings and one-to-one help for people with MDS or CMML and carers.United Kingdom
Sources and further reading
- Myelodysplastic Syndromes Treatment (PDQ), Health Professional Version
NCI, Accessed 2026-09-05 - Myelodysplastic Neoplasms/Syndromes (MDS)
EBMT Handbook / NCBI Bookshelf, Accessed 2026-09-05 - WHO fifth-edition classification: Myeloid and Histiocytic/Dendritic Neoplasms
WHO classification authors / Leukemia, Accessed 2026-09-05 - Indications for haematopoietic cell transplantation and CAR-T: 2025 EBMT practice recommendations
EBMT / Bone Marrow Transplantation, Accessed 2026-09-05 - Stem Cell and Bone Marrow Transplants for Cancer
NCI, Accessed 2026-09-05 - Donor and cord blood unit selection guidelines
NMDP / CIBMTR, Accessed 2026-09-05 - Comparison of the 2022 world health organization classification and international consensus classification in myelodysplastic syndromes/neoplasms
Blood Cancer Journal (via PMC), 2024-04-09; accessed 2026-09-26 - Join the registry
NMDP, Accessed 2026-09-24 - On modeling human leukocyte antigen-identical sibling match probability for allogeneic hematopoietic cell transplantation
Biology of Blood and Marrow Transplantation, March 2016 - Allogeneic Hematopoietic Cell Donor Selection: Contemporary Guidelines from the NMDP/CIBMTR
NMDP / CIBMTR, Transplantation and Cellular Therapy, 2025 - What is HLA? HLA basics, typing and matching
NMDP, Accessed 2026-09-26 - Matching with a patient
NMDP, Accessed 2026-09-26 - Implications of TP53 allelic state for genome stability, clinical presentation and outcomes in myelodysplastic syndromes
Nature Medicine (Bernard E, et al.), 2020; accessed 2026-09-26 - Allogeneic Hematopoietic Cell Transplantation Improves Outcome in Myelodysplastic Syndrome Across High-Risk Genetic Subgroups: Genetic Analysis of the Blood and Marrow Transplant Clinical Trials Network 1102 Study
Journal of Clinical Oncology (Versluis J, et al.), 2023; accessed 2026-09-26 - Biologic Assignment Trial of Reduced-Intensity Hematopoietic Cell Transplantation Based on Donor Availability in Patients 50-75 Years of Age With Advanced Myelodysplastic Syndrome
Journal of Clinical Oncology (Nakamura R, et al.; BMT CTN 1102), 2021; accessed 2026-09-26 - Outcomes with allogeneic hematopoietic stem cell transplantation in TP53-mutated myelodysplastic syndrome: A systematic review and meta-analysis
Critical Reviews in Oncology/Hematology (Shahzad M, et al.), 2024; accessed 2026-09-26 - Myelodysplastic syndromes (MDS): HCT consultation timing guidelines
NMDP, Accessed 2026-09-26 - Myelodysplastic Syndromes Treatment (PDQ), Patient Version
National Cancer Institute, Updated 2024-10-04; accessed 2026-09-26 - Pathology Reports (fact sheet)
National Cancer Institute, 2022-08-08; accessed 2026-09-26 - TP53 gene
MedlinePlus Genetics (NIH), Updated 2020-02-01; accessed 2026-09-26 - Li-Fraumeni syndrome
MedlinePlus Genetics (NIH), Updated 2020-06-01; accessed 2026-09-26 - Adult-onset hereditary myeloid malignancy and allogeneic stem cell transplantation
Frontiers in Oncology (Toya T, et al.), 2022; accessed 2026-09-26
This information explains a condition and its treatments. It cannot diagnose an illness or recommend treatment for an individual. Your care team can explain how the evidence applies to you. Written and source-checked by the Jada Bascom Foundation. Each page lists the published sources it draws on.
Ways to help
Someone may be waiting for a match.
Some people with MDS with biallelic TP53 inactivation (multi-hit TP53) are treated with a transplant from a donor. When no relative matches, that donor is often a stranger who joined a registry.
Join the registry
JBF points you to the official registry that serves your country. It explains who can join and what donation involves.
Help someone you love find a donor
If someone you love needs a donor, our family guide explains practical ways to help. A registration drive can add many potential donors at once, for them and for others.
Support this work
Gifts to the Jada Bascom Foundation support donor-awareness education like this page, community outreach, drive planning and referrals to official registries.
More in the library
Keep learning
Interactive storyWhy matching is hard: leukemiaHow leukemia affects blood production, when a donor transplant may help, and how inherited HLA markers shape the search for a suitable donor.Begin the storyPart of 2 diagnosis guides, each explaining how its subtypes fit together: Myelodysplastic syndromes (MDS) and Types of blood cancer.
