Acute myeloid leukaemia (AML)

Blood is made in the bone marrow by a hierarchy of stem and progenitor cells that mature, step by step, into red cells that carry oxygen, platelets that stop bleeding, and the many kinds of white cell that fight infection. In acute myeloid leukaemia, a cell partway along the myeloid branch of that hierarchy acquires genetic changes that lock it in an immature state and drive it to copy itself. The result is a marrow filling with identical, useless blasts — and a bloodstream progressively emptied of everything the marrow should have been making instead.

That mechanism explains almost everything about how AML behaves. It is called acute because untreated it progresses over weeks, not years: blasts double quickly, and the shortages they cause — of red cells, functioning white cells and platelets — become dangerous fast. It behaves like a liquid cancer rather than a lump: there is nothing to cut out, because the disease is everywhere the blood is, which is why surgery plays no role and chemotherapy has always been the foundation of treatment. And it is best understood as many diseases wearing one name: the specific genetic changes inside the blasts differ from patient to patient, and those differences — far more than age or symptoms — determine how the disease responds to chemotherapy and whether a transplant will be recommended.

AML is predominantly, though not exclusively, a disease of older adults, and it can arise out of the blue, evolve from prior marrow disorders such as myelodysplastic syndromes, or follow previous chemotherapy or radiotherapy given for another cancer. The distinction matters clinically: secondary and therapy-related AML tend to carry higher-risk genetics.

How treatment is organised shapes the experience as much as the drugs. AML care is inherently inpatient-heavy at the start — induction means weeks in hospital through the count nadir — and inherently team-based: haematologists, transplant physicians, microbiologists, transfusion services and specialist nurses run a single coordinated protocol. For families this means two practical things: the treating hospital matters (units that treat AML routinely run the fever protocols, the transfusion logistics and the trial portfolio that outcomes lean on), and the pace of information is front-loaded — the genetics that decide everything arrive within days, and the treatment plan often changes once between diagnosis and cycle one as results land. Neither is a sign of disorganisation; both are the disease’s standard shape.

One subtype deserves its own sentence. Acute promyelocytic leukaemia (APL) — defined by a specific chromosomal fusion — is a medical emergency at diagnosis because of bleeding risk, yet with modern targeted treatment it has become one of the most curable forms of adult leukaemia, usually without any transplant. It is the clearest illustration of why the genetic label on an AML matters more than the name.

AML announces itself through the shortages it creates, and the story is usually short — weeks of feeling progressively wrong, not months. The missing red cells cause the anaemia symptoms: tiredness out of proportion to activity, breathlessness climbing stairs, a pale complexion, sometimes pounding heartbeats or light-headedness. The missing functional white cells cause infections that keep coming back, respond slowly to antibiotics, or arrive unusually severely — a mouth ulcer that will not heal, a sore throat that lingers, fevers without an obvious source. The missing platelets cause the bleeding signs: bruises appearing without remembered knocks, tiny flat red-purple dots on the skin (petechiae), bleeding gums when brushing, nosebleeds that take too long to stop, and heavier periods.

Some features come from the blasts themselves rather than the shortages. Bone pain — often in the long bones or sternum — reflects a crowded marrow. Blasts can infiltrate the gums, making them swollen; the skin, causing firm purplish lumps; or, rarely, form solid deposits elsewhere. A very high blast count can thicken the blood enough to cause headaches, visual changes or breathlessness — leukostasis, one of the true emergencies of the disease. Loss of appetite, weight loss and drenching night sweats round out the picture.

None of these symptoms is specific to leukaemia, which is why the diagnosis is often first suspected not from a symptom but from a blood count taken to explain one. The practical message is about combinations and trajectories: tiredness plus bruising, infection plus petechiae, any of them worsening week on week, deserve a blood count promptly. Onset speed is itself a clue worth reporting: patients often date the change to within a fortnight — “I was fine at my birthday; by the wedding three weeks later I could not climb the stairs” — and that steep trajectory, so different from the slow drift of iron deficiency or the months of aplastic anaemia, moves AML up the differential before any test returns.

AML begins with acquired genetic damage in a single blood-forming cell — mutations and chromosomal rearrangements that arise during life and are not inherited in the ordinary case. Why a particular person’s cell acquires that damage usually has no identifiable answer; most people diagnosed with AML have no known exposure and nothing they could have done differently, a point worth stating plainly because self-blame is common and almost always misplaced.

The known contributors fall into a few groups. Prior marrow disease is the largest: myelodysplastic syndromes and some chronic marrow disorders can evolve into AML, which is why they are monitored long-term. Previous cancer treatment is the second: certain chemotherapy classes and radiotherapy can damage marrow stem cells, and therapy-related AML typically appears several years after the original treatment — a rare price of cures that, in the arithmetic of oncology, remain overwhelmingly worth it. High-dose ionising radiation is an established cause; prolonged occupational exposure to benzene is another, and is the reason industrial hygiene rules around solvents exist. Smoking is the one lifestyle exposure with consistent evidence of a modest risk increase.

A small share of AML arises on inherited ground: familial predisposition syndromes — including those involving RUNX1, CEBPA, DDX41 and GATA2 genes, and marrow-failure conditions such as Fanconi anaemia — raise lifetime risk. They matter beyond curiosity: when a related donor is being considered for transplant, teams check that the donor does not silently carry the same predisposition. the honest sentence for most patients is the one that recurs across this platform’s cancer pages — nothing they did caused this, and nothing they could reasonably have done would have prevented it.

One modern nuance is clonal haematopoiesis: many healthy older adults carry small blood-cell clones with AML-associated mutations, found incidentally as genetic testing spreads. The overwhelming majority never develop leukaemia, and no intervention is currently advised beyond, in defined cases, periodic counts — but the finding explains some “out of nowhere” diagnoses and is why incidental mutation reports deserve a haematologist’s interpretation rather than a search engine’s.

Risk factors describe populations, not verdicts on individuals — most people with several risk factors never develop AML, and most people with AML had none. Age is the strongest: incidence rises steeply from mid-life, and the disease’s biology tends to be more adverse in older patients. A history of myelodysplastic syndrome or another clonal marrow disorder is the strongest medical antecedent. Previous chemotherapy — particularly alkylating agents and topoisomerase II inhibitors — and radiotherapy carry a recognised delayed risk. Long-term occupational benzene exposure and high-dose radiation exposure are established environmental factors. Smoking modestly raises risk. Inherited predisposition syndromes and Down syndrome account for a small but important minority, increasingly identified now that genetic testing at diagnosis is routine.

A cluster of risk questions patients raise deserve direct answers: mobile phones, power lines, deodorants and hair dye have no credible evidence linking them to AML; previous ordinary X-rays contribute negligibly; and stress, whatever its other costs, does not cause leukaemia. The list of real causes is short and mostly unmodifiable — which is frustrating for prevention, and liberating for guilt.

AML is not staged by spread the way solid cancers are — it is everywhere the blood is from day one. What replaces staging is genetic risk classification: the chromosomes and mutations inside the blasts sort the disease into groups that predict how well chemotherapy alone is likely to work. The European LeukemiaNet (ELN) framework, used worldwide, is the usual reference. The group a patient falls into is the single biggest factor in whether a transplant is recommended in first remission.

The suspicion usually starts with a full blood count showing anaemia, low platelets and a white cell count that may be high, normal or low — but with blasts visible when the blood film is examined under the microscope. Confirmation and profiling then happen together, because modern treatment cannot be chosen from the diagnosis alone.

A bone marrow biopsy is the central test: a needle sample from the back of the pelvis, taken under local anaesthetic, examined for the proportion of blasts and their appearance. Flow cytometry — immunophenotyping — reads the proteins on the blast surface and confirms the myeloid lineage. Cytogenetics examines the chromosomes for the translocations and losses that anchor risk classification, and molecular panels sequence a set of genes — NPM1, FLT3, CEBPA, TP53, IDH1, IDH2 and others — whose mutations refine risk further and, increasingly, unlock targeted drugs. The same technologies later measure remission depth: MRD testing can find one leukaemic cell among thousands of normal ones, and its result has become one of the most important inputs to the transplant decision.

Around the marrow tests sit the practical ones: blood chemistry and clotting (deranged clotting is an emergency clue to APL), virology screening before treatment, a heart function scan before anthracycline chemotherapy, and a lumbar puncture only when symptoms suggest the uncommon spread to spinal fluid. HLA typing — the tissue-typing test used to match transplant donors — is done early in every patient who could conceivably need a transplant, so that a donor search never starts from zero later. For anyone who may want children after treatment, fertility preservation is discussed before chemotherapy begins wherever the clinical urgency allows.

Reading the reports is a skill families acquire fast, and two translations help. First: “blasts” on a report are the disease’s unit of measurement — under five percent in a recovering marrow is the remission threshold, not zero, because healthy marrows contain a few. Second: the genetics report is not a verdict but a routing instruction — the same words (favourable, intermediate, adverse) that sound like fortunes are actually treatment assignments, each with its own protocol and its own statistics. Asking the team to walk through the FISH and molecular lines once, slowly, repays the twenty minutes many times over.

AML care runs on daily counts. These are the values patients hear most, what each measures, and why teams watch them.

Untreated, AML’s complications are the shortages taken to their conclusion — overwhelming infection and serious bleeding — which is why treatment starts promptly once the profile is known. Two presentation emergencies deserve naming. Leukostasis, from a very high blast count thickening the circulation, can affect the brain and lungs and is treated urgently by bringing the count down. Disseminated intravascular coagulation — runaway clotting and bleeding at once — is characteristic of APL, and is the reason that subtype is treated as an emergency from the first suspicion. Tumour lysis syndrome, caused by the contents of rapidly dying blasts overwhelming the kidneys, belongs to the first days of therapy and is largely preventable with fluids and uric-acid-lowering drugs.

Most complications patients actually experience come during the treatment dips. Intensive chemotherapy empties the marrow before it recovers, so each course brings a window of very low counts: febrile neutropenia — fever with too few neutrophils — is the expected emergency of that window, managed with immediate antibiotics under protocols every haematology unit runs day and night. Transfusions of red cells and platelets bridge the gaps, and the numbers behind that sentence are worth knowing: platelet transfusions may run every few days at the nadir, red cells weekly, each preceded by compatibility checks that make reactions rare. Iron accumulates over many transfusions and is assessed after treatment ends. Mucositis, nausea, hair loss and profound fatigue are the common companions of induction. Longer-term, survivors carry the late risks of their cure: heart effects from anthracyclines, fertility impairment, and — for those transplanted — the distinct landscape of graft-versus-host disease and immunosuppression that the transplant pathway section introduces.

There is no diet, supplement or screening test that prevents AML, and a page that pretended otherwise would be selling something. The honest levers are few and mostly structural. Not smoking removes the one common lifestyle exposure with consistent evidence. Occupational protections around benzene and radiation exist precisely because of this disease, and using them properly matters more than anything an individual can buy. People previously treated with chemotherapy or radiotherapy, and people with myelodysplastic syndromes or known predisposition syndromes, benefit not from worry but from the follow-up they are already offered — therapy-related and secondary AML are the situations where scheduled blood counts genuinely catch disease early.

For everyone else, the realistic protection is early recognition: knowing that the combination of unexplained bruising, recurrent infection and mounting fatigue is a blood-count-today symptom cluster, not a wait-and-see one. AML found at a routine count, before complications, starts treatment from a stronger position — and the difference between weeks is real in a disease that moves at this speed.

AML treatment has a two-act structure. The first act aims at remission: clearing the marrow of visible leukaemia so that normal blood production returns. For patients fit for intensive treatment, that means induction chemotherapy — classically an anthracycline plus cytarabine, the “7+3” backbone used for decades — given in hospital across several weeks including the count-recovery period. Targeted drugs now join the backbone when the leukaemia’s genetics invite them: FLT3 inhibitors such as midostaurin for FLT3-mutated disease, and others in specific settings. For patients whose age or health rules out intensive induction, the combination of the BCL-2 inhibitor venetoclax with a hypomethylating agent (azacitidine or decitabine) has become a widely used, genuinely effective alternative — one of the larger practical advances of recent years. APL is treated on its own path — all-trans retinoic acid with arsenic trioxide — usually without conventional chemotherapy at all. A practical translation of “intensive versus non-intensive”: the choice is made on biological fitness — organ function, performance status, frailty measures — not birthdays, and it is revisited rather than fixed; some patients judged non-intensive at a crisis-laden diagnosis prove fit for more after stabilisation, and the venetoclax era has blurred the border by giving the “gentler” road genuinely disease-modifying force. Asking WHY a particular intensity was chosen, and what would change it, is a legitimate and clarifying question at any AML consultation.

The second act decides how to keep the remission, and this is where the risk groups earn their keep. Favourable-risk disease is usually consolidated with further cytarabine-based chemotherapy alone. Adverse-risk disease usually proceeds to an allogeneic stem cell transplant in first remission, because chemotherapy alone rarely holds it. Intermediate-risk disease is decided case by case, with MRD results, donor availability and fitness all weighing in. Throughout both acts runs supportive care — transfusions, infection prophylaxis and treatment, and increasingly maintenance drugs such as oral azacitidine for selected non-transplanted patients.

Relapsed or refractory disease is treated with re-induction or targeted agents — IDH inhibitors for IDH-mutated disease, FLT3 inhibitors such as gilteritinib, venetoclax combinations — with the near-universal goal of reaching a remission solid enough to carry into transplant, which at that point is the only established route to cure. Clinical trials are a mainstream option at every stage of AML, not a last resort, and asking about them is always legitimate.

Supportive care is half the treatment and deserves naming: transfusion support runs throughout (many patients receive dozens of units across a course — one reason blood donation systems matter to this disease); infection defence is layered from protective isolation during nadirs through prophylactic antifungals to the fever protocol every unit drills; nausea control has improved beyond recognition; and growth-factor support shortens some neutropenic windows. Daily life inside a cycle has a rhythm patients learn — the treatment days, the dip, the recovery bloods, the brief home interval — and units increasingly publish that rhythm in advance so families can plan work and childcare around it. Nutrition, gentle activity even on the ward, and psychological support are prescribed alongside the chemotherapy because each measurably affects how patients tolerate it.

Central lines deserve their own paragraph because they surprise families: almost every intensively treated patient receives one — a PICC or tunnelled catheter — through which chemotherapy, transfusions, antibiotics and blood draws all run, sparing hundreds of needle punctures. Line care (dressings, flushes, the redness-and-fever rules) becomes part of household routine between cycles, and line infections, the main hazard, are exactly what the low-threshold fever protocol exists to catch.

An allogeneic stem cell transplant — a bone marrow transplant for leukaemia, in everyday language — replaces the patient’s blood-forming system with a donor’s; the stem cell transplant guide covers the procedure itself. Conditioning chemotherapy — sometimes with radiotherapy — clears the marrow, donor stem cells are infused like a transfusion, and over the following weeks they engraft and rebuild blood production. The cure mechanism is only partly the conditioning: the deeper effect is immunological, the graft-versus-leukaemia effect, in which the new immune system recognises residual leukaemic cells as foreign and eliminates them. That same recognition, aimed at healthy tissue, is graft-versus-host disease — the central risk that transplant medicine spends most of its effort preventing and treating.

Who is recommended a transplant follows from everything above: adverse-risk genetics in first remission, persistent measurable residual disease, and relapsed disease brought back into remission are the classic indications, always weighed against age, organ fitness and the availability of a suitable donor. Donors are matched by HLA tissue type: a fully matched sibling remains the classic first choice, but matched unrelated donors found through international registries, half-matched (haploidentical) family donors under modern protocols, and cord blood have widened access enormously — most patients who need a transplant can now find a workable donor. Reduced-intensity conditioning has extended the option to older patients who could not tolerate the full-strength version.

For patients considering treatment abroad, the honest framing is this: an AML transplant is not a procedure booked like a flight, but the final step of a pathway that starts with induction, risk profiling and donor search — much of which may happen at home. What a receiving centre needs is the complete file: diagnostic marrow reports, cytogenetics and molecular results, MRD status, treatment records and HLA typing of patient and any family donors. The platform’s role is to carry that file to a transplant team and let them judge; no page, including this one, can tell an individual that a transplant is right for them.

Outcomes in AML span an unusually wide range, and any single number would mislead — which is why this page gives none without its context. The spread is driven by the same factors that drive treatment: age and fitness, the genetic risk group, and the depth of remission achieved. Younger patients with favourable-risk genetics are cured by chemotherapy alone in a substantial majority of cases; APL, treated on modern targeted protocols, has outcomes good enough that it is discussed as a curable disease. Adverse-risk and relapsed disease are far harder, and it is precisely there that transplantation changes the arithmetic, converting many otherwise incurable situations into long-term remissions.

The field is also visibly moving. Venetoclax combinations have given older patients real remissions where supportive care was once the only offer; targeted inhibitors of FLT3 and IDH mutations have added options at diagnosis and relapse; MRD monitoring is steadily replacing one-size-fits-all rules with individually timed decisions. Published survival statistics, by their nature, describe patients treated years ago under earlier protocols — a reason for measured optimism when reading them, and a reason this page cites its sources rather than quoting figures that will age. For an individual, the meaningful prognosis is the one their own team gives after cytogenetics, molecular results and response to induction are in hand — usually within the first month of treatment.

Life after AML treatment has its own arc. Counts and energy rebuild over months, not weeks; immunity lags behind counts, so revaccination is scheduled and early crowd-avoidance advised; work returns in stages for most; and follow-up thins from weekly to monthly to a few visits a year, watching for the relapse signs listed above. Survivors of intensive chemotherapy carry defined late risks — cardiac follow-up after anthracyclines, fertility questions addressed before treatment — and transplanted patients follow the fuller survivorship path their transplant clinic runs. What most patients report wanting to hear, and what the data support saying, is that a completed treatment with a sustained remission returns most people to ordinary life: employment, family, travel, sport, in time.

Relapse surveillance, concretely: blood counts at every follow-up visit, with marrow examinations reserved for changes rather than routine in most protocols; molecularly monitorable subtypes (NPM1 prominently) increasingly add periodic PCR testing, which can see relapse building months before counts move — lead time that modern pre-emptive treatment strategies are learning to use. Follow-up frequency typically halves yearly from monthly beginnings, and most relapses, where they occur, declare within the first two years — the statistical basis of the milestone anniversaries patients rightly celebrate.