Blood & Lymphoreticular

Acute myeloid leukemia: workup and induction overview

Clinical Overview and When to Suspect AML

— Median age at diagnosis ~68 years; incidence rises sharply after age 60

— Defined by ≥20% myeloid blasts in marrow or peripheral blood, OR presence of AML-defining genetic abnormalities regardless of blast count (t(8;21), inv(16)/t(16;16), t(15;17), and others per WHO/ICC 2022)

— New unexplained pancytopenia or bicytopenia, especially with circulating blasts

— Fatigue + easy bruising/petechiae + recurrent or atypical infection in an older adult

— Isolated leukocytosis with "left shift" that includes blasts (not just bands)

— Bleeding out of proportion to platelet count → think acute promyelocytic leukemia (APL) with DIC

— Gingival hypertrophy, leukemia cutis, or chloroma (myeloid sarcoma) → monocytic subtypes (FAB M4/M5)

— Hyperleukocytosis (WBC >50–100k) with dyspnea, confusion, priapism → leukostasis emergency

— Prior cytotoxic chemo (alkylators, topo II inhibitors), prior radiation → therapy-related AML

— Antecedent MDS, MPN, or aplastic anemia

— Down syndrome, Fanconi anemia, Li-Fraumeni, germline CEBPA/RUNX1/DDX41 mutations

— Benzene exposure, smoking

Acute myeloid leukemia (AML) = clonal proliferation of myeloid blasts with arrest of differentiation, leading to marrow failure and tissue infiltration

When to suspect AML in clinic or ED:

Predisposing risks that should heighten suspicion:

Board pearl: A patient presenting with pancytopenia + DIC + bleeding is APL until proven otherwise — start ATRA empirically before genetic confirmation because early death from hemorrhage is the main killer.

Step 3 management: First moves in suspected AML — CBC with manual differential and peripheral smear, coags (PT/PTT/fibrinogen/D-dimer), CMP, LDH, uric acid, phosphorus, calcium, type & screen, blood cultures if febrile, then urgent heme/onc consult and admission. Do not send the patient home pending outpatient workup.

Presentation Patterns and Key History

— Anemia → fatigue, exertional dyspnea, pallor, angina in older patients, lightheadedness

— Thrombocytopenia → petechiae, gum bleeding, epistaxis, menorrhagia, easy bruising, rarely intracranial hemorrhage

— Neutropenia → fever, recurrent sinopulmonary infections, perirectal pain, oral ulcers, sepsis without obvious source

— AML symptoms typically evolve over days to a few weeks

— Subacute fatigue over many months suggests MDS, CLL, or chronic anemia rather than de novo AML

— A patient with known MDS who deteriorates rapidly → suspect MDS transformation to AML

— Headache, visual changes, focal neuro deficits (CNS leukostasis or leukemic meningitis — more common in monocytic AML and APL)

— Dyspnea, hypoxia (pulmonary leukostasis)

— Bone pain, especially sternum, ribs, pelvis (marrow expansion)

— Abdominal fullness from hepatosplenomegaly (less prominent than in ALL/CML)

— Painless skin nodules (leukemia cutis) or testicular swelling (rare in AML, more in ALL)

— Prior chemo agent and dose timing (alkylators → 5–7 yr latency, topo II inhibitors → 1–3 yr)

— Occupational benzene, petroleum, pesticide exposure

— Tobacco history

— Family history of cytopenias, early MDS/AML, BMF syndromes → think germline predisposition (DDX41, RUNX1, CEBPA, GATA2)

Three classic symptom clusters, all reflecting marrow failure:

Tempo of illness — important Step 3 discriminator:

Symptoms of organ infiltration/leukostasis to ask about:

Targeted exposure and family history:

Key distinction: Bone pain + lymphadenopathy + hepatosplenomegaly + CNS symptoms in a young adult tilts toward ALL; isolated marrow failure + Auer rods + older age tilts toward AML.

Board pearl: Always ask about gum bleeding plus easy bruising in a patient who looks "too sick too fast" — this is the APL stem. Ordering ATRA before karyotype results is the right answer.

Step 3 management: Document baseline performance status (ECOG), comorbidities, and goals of care early — these drive whether the patient is a candidate for intensive induction vs. venetoclax-based therapy.

Physical Exam Findings and Hemodynamic Assessment

— Pallor of conjunctiva, palmar creases, nail beds

— Petechiae (non-blanching, pinpoint) on lower extremities, palate, buccal mucosa

— Ecchymoses out of proportion to trauma; wet purpura on oral mucosa = high bleeding risk

— Febrile, ill-appearing in neutropenic sepsis

— Gingival hyperplasia infiltrated by leukemic cells → monocytic AML (M4/M5) classic

— Retinal hemorrhages, Roth spots, papilledema (leukostasis or thrombocytopenia)

— Oral candidiasis, herpetic ulcers from neutropenia

— Lymphadenopathy uncommon in AML (more in ALL/CLL) — if prominent, reconsider diagnosis

— Mild hepatosplenomegaly possible but massive splenomegaly suggests CML or myelofibrosis

— Leukemia cutis — violaceous, non-tender papules/nodules, again favoring monocytic subtypes

— Sweet syndrome (acute febrile neutrophilic dermatosis) — tender erythematous plaques, paraneoplastic

— Chloroma/myeloid sarcoma — firm green-tinged subcutaneous mass; can be presenting feature

— Altered mentation, focal deficits, cranial neuropathies

— Tachypnea, hypoxia, diffuse crackles → pulmonary leukostasis (often radiographically subtle)

— Priapism in males with very high WBC

— Tachycardia from anemia or sepsis

— Hypotension → septic shock vs. hemorrhagic shock (especially APL with DIC)

— Check capillary refill, mentation, urine output before tumor lysis hydration

General appearance:

HEENT:

Lymph nodes / abdomen:

Skin:

Neuro and pulmonary — assess for leukostasis:

Hemodynamic assessment:

Board pearl: Gingival hyperplasia + leukemia cutis + monocytosis = monocytic AML; this subtype also has the highest risk of CNS involvement, so include lumbar puncture in workup if neuro symptoms are present (after platelets corrected).

Step 3 management: If WBC >50k with respiratory or neurologic symptoms → activate leukostasis protocol: IV fluids cautiously, urgent cytoreduction (hydroxyurea, leukapheresis), avoid pRBC transfusion until WBC reduced (raises viscosity), platelets are safe to transfuse.

Diagnostic Workup — Initial Labs, Smear, Imaging

— Anemia (normocytic), thrombocytopenia, WBC variable (low, normal, or markedly elevated)

— Circulating blasts often present; absence does not exclude AML

— Order manual smear review — auto-differentials misclassify blasts

— Auer rods (pink/red needle-like cytoplasmic inclusions) → pathognomonic for AML

— Faggot cells (bundles of Auer rods) → APL

— Pseudo-Pelger-Huët cells, dysplastic neutrophils → AML with myelodysplasia-related changes

— Monocytoid blasts with folded nuclei → monocytic lineage

— PT, aPTT, fibrinogen, D-dimer

— Fibrinogen <150 mg/dL + elevated D-dimer + bleeding = DIC, suspicious for APL

— Repeat coags every 6–12 hours in suspected APL until stable

— BMP, magnesium, phosphorus, calcium, uric acid, LDH

— Elevated LDH and uric acid reflect high turnover

— Baseline creatinine guides allopurinol vs. rasburicase choice

— Blood cultures ×2, urinalysis/culture, CXR, lactate

— Empiric broad-spectrum antipseudomonal antibiotics (cefepime, pip-tazo, or meropenem) within 1 hour for neutropenic fever (ANC <500 or expected to drop)

— CXR for infection, leukostasis, mediastinal mass (more in ALL)

— Echocardiogram before anthracycline (baseline LVEF — daunorubicin/idarubicin are cardiotoxic)

— CT head if neuro symptoms (rule out hemorrhage before LP)

— Type & crossmatch, viral serologies (HIV, HBV, HCV), pregnancy test, HLA typing if young/transplant candidate

CBC with manual differential — cornerstone:

Peripheral smear findings:

Coagulation panel — mandatory before any procedure:

Chemistry / tumor lysis labs:

Infection workup if febrile:

Imaging:

Pre-transfusion / pre-chemo labs:

Board pearl: Always check fibrinogen and D-dimer in any new acute leukemia — missing APL DIC kills patients in the first 48 hours.

CCS pearl: Order CBC w/ diff, smear, PT/PTT/fibrinogen/D-dimer, CMP, LDH, uric acid, blood cultures, CXR, echo, type & screen, and heme/onc consult at the same clock-tick — bundling orders advances simulated time efficiently.

Diagnostic Workup — Confirmatory Studies

— Send for morphology, flow cytometry, cytogenetics (karyotype), FISH, and molecular/NGS panel

— Diagnosis confirmed by ≥20% myeloid blasts, OR any of the AML-defining cytogenetic lesions regardless of blast %: t(15;17) PML-RARA, t(8;21) RUNX1-RUNX1T1, inv(16)/t(16;16) CBFB-MYH11, KMT2A rearrangements (per ICC/WHO)

— If marrow is "dry tap" (myelofibrosis), peripheral blood with high blast count + flow can suffice

— Myeloid markers: CD13, CD33, CD117, MPO

— Monocytic: CD14, CD64, CD11b, lysozyme

— Megakaryocytic (M7): CD41, CD61

— Distinguishes AML from ALL (CD19, CD10, TdT) and from mixed-phenotype acute leukemia

— Favorable: t(15;17), t(8;21), inv(16)/t(16;16), biallelic CEBPA, NPM1-mutated without FLT3-ITD

— Intermediate: normal karyotype with various combinations, FLT3-ITD with NPM1

— Adverse: complex karyotype (≥3 abnormalities), monosomy 5/7, del(5q), 17p abnormalities, TP53 mutation, ASXL1, RUNX1, FLT3-ITD without NPM1, KMT2A rearrangements (most)

— FLT3-ITD/TKD → midostaurin, quizartinib (ITD only)

— IDH1 → ivosidenib; IDH2 → enasidenib

— NPM1, CEBPA → prognostic, also drive MRD monitoring

— TP53 → poor response to standard induction; consider clinical trial

— FISH for t(15;17) or RT-PCR for PML-RARA transcript

— Do not wait for results before starting ATRA

— Only if CNS symptoms or high-risk subtype (monocytic, hyperleukocytosis); after platelet correction ≥50k

Bone marrow aspirate and biopsy — definitive test:

Flow cytometry / immunophenotype:

Cytogenetics — defines risk:

Molecular panel (NGS) — actionable mutations:

APL-specific confirmation:

Lumbar puncture:

Key distinction: APL = "promyelocytes with faggot Auer rods + DIC + t(15;17)" — treated with ATRA + arsenic trioxide (chemo-free in low/intermediate risk), survival >90%, completely different pathway from other AMLs.

Board pearl: A normal karyotype does not equal good prognosis — risk is driven by molecular profile (NPM1, FLT3, TP53, etc.). Always wait for NGS before finalizing risk category.

Risk Stratification and First-Line Management Logic

— Age alone is not the criterion — performance status, comorbidities (HCT-CI score), end-organ function, and patient preference matter

— "Fit" → intensive induction (7+3); "unfit" → venetoclax + azacitidine/decitabine or low-dose cytarabine

— Cardiac (LVEF <50%), renal, hepatic dysfunction shift toward less intensive therapy

— Favorable risk → chemotherapy consolidation (high-dose cytarabine) usually sufficient

— Intermediate or adverse risk → allogeneic stem cell transplant in first complete remission if fit and donor available

— TP53-mutated → poor outcomes with all current therapies → clinical trial

— Low/intermediate risk APL (WBC ≤10k): ATRA + arsenic trioxide, no cytotoxic chemo

— High-risk APL (WBC >10k): ATRA + arsenic ± anthracycline or gemtuzumab

— Cure rate >90% with appropriate therapy

— Central venous access (tunneled or PICC) once platelets corrected

— Echo for baseline LVEF

— Hepatitis B/C, HIV serologies

— Fertility preservation discussion in reproductive-age patients (sperm banking, oocyte preservation if time permits)

— HLA typing of patient and siblings if transplant candidate

— Dental and infection screening when feasible

— IV hydration (2–3 L/m²/day), allopurinol for lower-risk, rasburicase for high WBC, high LDH, or pre-existing renal dysfunction

— Monitor K, phos, Ca, uric acid, Cr q6–12h during induction

Fitness-for-induction assessment is the first decision branch:

ELN 2022 risk stratification (used to guide post-remission therapy):

APL pathway is entirely separate:

Pre-treatment essentials before starting induction:

Tumor lysis prophylaxis:

Step 3 management: The Step 3 stem often asks "next best step" once AML is confirmed → answer is usually risk-stratify with cytogenetics/molecular, start TLS prophylaxis, begin induction chemo, and HLA-type for transplant evaluation if intermediate/adverse risk.

Board pearl: t(15;17) = give ATRA now; FLT3-ITD = add midostaurin to 7+3; IDH1/2 mutation in older unfit patient = ivosidenib/enasidenib option; TP53 = trial or hypomethylating + venetoclax with realistic expectations.

Pharmacotherapy — Induction Regimens

— Cytarabine 100–200 mg/m²/day continuous infusion × 7 days

— Anthracycline: daunorubicin 60–90 mg/m²/day × 3 days OR idarubicin 12 mg/m²/day × 3 days

— Day 14 marrow assessment: if residual disease, give re-induction; if hypocellular, await count recovery

— Complete remission (CR) defined as <5% marrow blasts, ANC >1000, platelets >100k

— FLT3-mutated (ITD or TKD): add midostaurin 50 mg PO BID days 8–21

— CD33-positive favorable/intermediate risk: consider adding gemtuzumab ozogamicin (anti-CD33 ADC) — improves survival in CBF leukemias

— Therapy-related AML or AML with MDS-related changes: CPX-351 (liposomal daunorubicin + cytarabine) preferred over standard 7+3 in fit patients 60–75

— Venetoclax + azacitidine or venetoclax + decitabine — now standard for unfit/older patients; CR/CRi ~65%, median OS ~14.7 mo (VIALE-A)

— Venetoclax requires careful ramp-up with TLS prophylaxis (start 100 → 200 → 400 mg)

— Alternative: low-dose cytarabine + venetoclax; or hypomethylator monotherapy if frail

— IDH1: ivosidenib ± azacitidine; IDH2: enasidenib (relapsed setting primarily)

— ATRA 45 mg/m²/day + arsenic trioxide 0.15 mg/kg/day (low/intermediate risk)

— Monitor for differentiation (APL) syndrome: fever, dyspnea, weight gain, pulmonary infiltrates, hypotension → treat with dexamethasone 10 mg IV BID, hold ATRA only if severe

— QTc monitoring with arsenic; correct K and Mg aggressively

— Transfuse platelets <10k (or <20k with fever/bleeding); pRBC for Hgb <7–8

— Antifungal prophylaxis (posaconazole), antiviral (acyclovir), PJP prophylaxis with venetoclax

— Empiric antibiotics within 1 hour of neutropenic fever

Standard intensive induction: "7+3" for fit, non-APL AML:

Targeted additions based on mutations:

Less-intensive (unfit) induction:

APL induction — separate algorithm:

Supportive care during induction:

Board pearl: Differentiation syndrome in APL = give dexamethasone immediately, do not stop ATRA/ATO unless life-threatening — pulling ATRA risks DIC rebound.

Expanded Pharmacology and Post-Remission Therapy

— Favorable risk (CBF leukemias, NPM1+/FLT3−): high-dose cytarabine (HiDAC) 3 g/m² q12h on days 1, 3, 5 × 3–4 cycles

— Intermediate/adverse risk: proceed to allogeneic HSCT in CR1 if fit with donor

— FLT3-mutated: maintenance midostaurin post-consolidation; gilteritinib for relapsed/refractory FLT3-mutated AML

— Oral azacitidine (CC-486) maintenance prolongs survival in patients who achieved CR but cannot undergo transplant (QUAZAR)

— Cerebellar toxicity (ataxia, dysmetria) — check cerebellar exam before each dose; hold if abnormal, especially in patients >60 or with renal dysfunction

— Conjunctivitis → prophylactic corticosteroid eye drops

— Hand-foot syndrome, hepatotoxicity, myelosuppression

— Cumulative dose limits: daunorubicin ~550 mg/m², idarubicin ~150 mg/m²

— Baseline and surveillance echo; dexrazoxane considered in high-cumulative-dose settings

— Strong CYP3A inhibitors (azole antifungals like posaconazole, voriconazole) → reduce venetoclax dose by 50–75%

— TLS risk highest at first dose escalation; monitor labs q6–8h during ramp

— Neutropenia management: G-CSF, dose interruption between cycles

— FLT3 mutated → gilteritinib

— IDH1 → ivosidenib; IDH2 → enasidenib

— CD33+ → gemtuzumab

— Re-induction with FLAG-IDA, MEC, or CLAG-M; allo-HSCT in CR2

— Best curative option for intermediate/adverse risk

— Matched related > matched unrelated > haploidentical/cord

— Complications: GVHD, CMV reactivation, veno-occlusive disease, infections

— Post-transplant maintenance sorafenib or gilteritinib in FLT3+ patients

Consolidation after CR — risk-adapted:

HiDAC toxicities — high-yield:

Anthracycline cardiotoxicity:

Venetoclax-specific issues:

Relapsed/refractory AML options:

Allogeneic HSCT essentials:

Step 3 management: A patient achieves CR1 with intermediate-risk AML and has a matched sibling — the answer is proceed to allogeneic HSCT in first remission, not additional chemotherapy cycles.

Board pearl: Before each HiDAC dose, document a normal cerebellar exam — finger-to-nose, heel-shin, gait. New ataxia means hold the next dose immediately.

Special Populations — Elderly and Renal/Hepatic Impairment

— Make up the majority of AML patients; outcomes worse due to adverse biology (more TP53, complex karyotype, prior MDS) and comorbidities

— Standard of care for unfit: venetoclax + azacitidine (or decitabine) — VIALE-A showed median OS 14.7 mo vs. 9.6 mo with aza alone

— Assess with geriatric tools: ECOG, HCT-CI, gait speed, IADLs

— Avoid 7+3 if ECOG ≥3, severe cardiac/renal/hepatic dysfunction, or patient preference favors quality of life

— Polypharmacy review — drug interactions with venetoclax (CYP3A) are critical

— Goals-of-care discussion early; many older patients prefer outpatient hypomethylator-based therapy

— Palliative care co-management improves quality of life and may improve survival

— Rasburicase preferred over allopurinol for TLS in pre-existing renal dysfunction or very high tumor burden

— Cytarabine: standard doses generally tolerated; HiDAC contraindicated if CrCl <60 in older adults (high cerebellar toxicity risk) — use reduced dose 1–1.5 g/m²

— Methotrexate (intrathecal) — adjust for renal function

— Avoid nephrotoxins (aminoglycosides, IV contrast, NSAIDs) during induction

— Anthracyclines: reduce dose if bilirubin >1.2 (daunorubicin 75% dose) or >3 (50% dose)

— Venetoclax: caution in severe hepatic impairment

— Monitor LFTs throughout induction; midostaurin and gilteritinib both can cause hepatotoxicity

— Baseline LVEF <50% → avoid anthracyclines; consider CPX-351 cautiously or non-anthracycline regimen

— Prior MI, severe CAD → coordinate with cardio-oncology

Older adults (≥75 or unfit ≥60):

Frailty considerations:

Renal impairment:

Hepatic impairment:

Cardiac comorbidity:

Key distinction: "Fit" 70-year-old with EF 60% and no comorbidities can receive 7+3 with potential cure; a "frail" 65-year-old with EF 35%, CKD stage 4 should receive venetoclax + hypomethylator with palliative intent.

Step 3 management: When the stem describes an 80-year-old with new AML, ECOG 2, mild CKD → answer is almost always venetoclax + azacitidine with rasburicase prophylaxis, not 7+3.

Special Populations — Pregnancy and Pediatric/Young Adult Considerations

— First trimester: anthracyclines and cytarabine are teratogenic — discuss therapeutic termination vs. delaying chemo (rarely safe)

— Second/third trimester: 7+3 can be given with relatively low fetal risk; idarubicin crosses placenta more readily than daunorubicin → daunorubicin preferred

— Avoid ATRA in first trimester (severe teratogen — retinoic acid embryopathy); can be used in 2nd/3rd

— Arsenic trioxide contraindicated throughout pregnancy

— Multidisciplinary team: heme/onc, MFM, neonatology

— Delivery planning: avoid delivery during neutropenic/thrombocytopenic nadir; allow ≥3 weeks between last chemo and delivery

— Chemotherapy contraindicates breastfeeding

— Contraception during and ≥6–12 months after therapy

— Discuss before induction — sperm banking is fast; oocyte/embryo cryopreservation requires 2 weeks (often not feasible if urgent induction needed)

— GnRH agonists during chemo — limited evidence, may consider in young women

— Different biology: more KMT2A rearrangements, t(8;21), inv(16); less TP53

— Generally treated on cooperative-group protocols (COG)

— Down syndrome–associated AML (especially <4 years, GATA1 mutation, M7 megakaryoblastic) has excellent prognosis with reduced-intensity therapy

— Transient abnormal myelopoiesis (TAM) in Down syndrome neonates — often self-resolves but 20–30% later develop AML

— Childhood cancer survivors with alkylator or topo II exposure

— Poor prognosis; transplant often required

AML in pregnancy — rare but high-stakes:

Postpartum / lactation:

Fertility preservation (all reproductive-age patients):

Pediatric and AYA AML:

Therapy-related AML in cancer survivors:

Board pearl: Down syndrome + young child + M7 AML + GATA1 mutation = paradoxically excellent outcome with reduced-dose chemo — opposite of adult AML.

Step 3 management: A 28-year-old woman with newly diagnosed AML — order pregnancy test, offer fertility preservation consultation before chemo, document the discussion. If pregnant in T2/T3, treat with daunorubicin-based 7+3, not idarubicin.

Complications and Adverse Outcomes

— Hyperuricemia, hyperkalemia, hyperphosphatemia, hypocalcemia, AKI

— Highest risk: high WBC, high LDH, bulky disease, venetoclax ramp-up

— Prevention: aggressive IV hydration, rasburicase for high risk, allopurinol for low/intermediate

— Manage hyperkalemia urgently; renal replacement if refractory

— ANC <500 + temp ≥38.3°C once or ≥38.0°C sustained 1 hour

— Empiric cefepime, piperacillin-tazobactam, or meropenem within 1 hour

— Add vancomycin for line infection, soft tissue, severe mucositis, hemodynamic instability

— Add antifungal (voriconazole, caspofungin, ambisome) if fever persists >4–7 days

— Galactomannan and beta-D-glucan for invasive aspergillosis surveillance

— Platelet transfusion threshold <10k prophylactic, <20k with fever/infection, <50k for procedures

— APL DIC: fibrinogen >150 mg/dL (cryoprecipitate), platelets >30–50k, FFP for elevated INR

— Intracranial hemorrhage is the leading early-death cause in APL

— Pulmonary infiltrates, hypoxia, mental status changes

— Cytoreduce with hydroxyurea ± leukapheresis; avoid pRBC transfusion until WBC down

— Initiate definitive induction concurrently

— Fever, dyspnea, weight gain, pleural/pericardial effusion, hypotension, AKI

— Treat: dexamethasone 10 mg IV BID × ≥3 days; continue ATRA/ATO unless life-threatening

— Anthracycline cardiotoxicity (acute arrhythmias, chronic cardiomyopathy)

— Cytarabine: cerebellar toxicity, conjunctivitis, pancreatitis, "ara-C syndrome" (fever, rash, myalgias)

— Mucositis, typhlitis (neutropenic enterocolitis — surgical emergency rarely)

— Venetoclax: profound neutropenia, TLS

— Secondary malignancies, infertility, chronic GVHD post-transplant

— Cardiomyopathy years after anthracyclines

Tumor lysis syndrome (TLS):

Neutropenic fever and sepsis:

Bleeding and DIC:

Leukostasis:

Differentiation syndrome (APL):

Chemotherapy-specific complications:

Late effects:

Board pearl: Right lower quadrant pain + fever + neutropenia + bowel wall thickening on CT = typhlitis (neutropenic enterocolitis) — manage with bowel rest, broad-spectrum antibiotics including anaerobic coverage, surgery only for perforation/necrosis.

When to Escalate Care — ICU, Consult, Inpatient Triage

— Risk of rapid decompensation from infection, bleeding, leukostasis, TLS

— Heme/onc consult on day of diagnosis

— Tertiary/transplant-capable center transfer for younger or transplant-eligible patients

— Hemodynamic instability or septic shock requiring vasopressors

— Respiratory failure (leukostasis, ARDS, pulmonary hemorrhage)

— Severe TLS with AKI requiring CRRT, refractory hyperkalemia

— Intracranial hemorrhage

— Severe differentiation syndrome with hypoxia/multi-organ involvement

— Major bleeding requiring massive transfusion

— Hematology/oncology — primary management

— Infectious disease — neutropenic fever, fungal infections

— Cardio-oncology — anthracycline candidacy, surveillance

— Reproductive endocrinology — fertility preservation

— Palliative care — symptom management, goals of care (early, not last-resort)

— Transfusion medicine — for refractory thrombocytopenia or alloimmunization

— Stem cell transplant team — for intermediate/adverse risk, fit candidates

— Community hospital → academic/NCI-designated center if not equipped for induction or transplant

— Ensure transfer occurs before clinical deterioration; do not wait for failure

— Direct admission to leukemia service preferred over ED handoff

— Address before initiating induction

— Document decision-maker, advance directives

— Revisit at key inflection points (CR vs. non-response, relapse, transplant decision)

All newly diagnosed AML patients require hospital admission — no outpatient workup:

ICU triggers:

Subspecialty consults — typical bundle:

Transfer of care considerations:

Code status and goals of care:

CCS pearl: On the CCS case, advancing time after orders is fine, but always change location to inpatient and call heme/onc consult in the first move; if WBC >100k with respiratory symptoms, change to ICU, initiate hydroxyurea + leukapheresis, then advance the clock in short intervals to catch deterioration.

Step 3 management: Persistent neutropenic fever despite 96 hours of broad-spectrum antibiotics → add empiric antifungal, obtain chest CT (halo sign, nodules → aspergillosis), send galactomannan, and broaden ID workup.

Key Differentials — Other Hematologic Malignancies

— Younger patients (peak childhood, second peak >50)

— Lymphadenopathy, hepatosplenomegaly, mediastinal mass (T-ALL), CNS involvement common

— Blasts express TdT, CD19, CD10 (B-ALL); CD3, CD7 (T-ALL); no MPO, no Auer rods

— Treatment includes CNS prophylaxis (intrathecal chemo) and prolonged maintenance — different paradigm from AML

— Philadelphia chromosome (BCR-ABL1) in ~25% of adult B-ALL → add TKI (imatinib, dasatinib, ponatinib)

— Blasts co-express myeloid and lymphoid markers

— Treated with ALL-like regimens often, transplant in CR1

— Prior chronic-phase CML with Philadelphia chromosome

— Massive splenomegaly, basophilia, marked leukocytosis with full spectrum of myeloid maturation

— Blast crisis: ≥20% blasts → resembles AML (myeloid blast crisis) or ALL (lymphoid blast crisis)

— Treat with TKI + induction-style chemo + transplant

— Cytopenias + dysplasia + <20% blasts

— Can transform to AML

— AML with myelodysplasia-related changes is a distinct WHO category — worse prognosis, often treated with CPX-351

— Polycythemia vera, essential thrombocythemia, primary myelofibrosis

— Can transform to AML ("post-MPN AML") — historically very poor outcomes

— JAK2, CALR, MPL mutations

— Skin nodules, marrow involvement, CD4+CD56+CD123+

— Treated with tagraxofusp (anti-CD123) + transplant

Acute lymphoblastic leukemia (ALL):

Mixed-phenotype acute leukemia (MPAL):

Chronic myeloid leukemia (CML) in blast crisis:

Myelodysplastic syndrome (MDS):

Myeloproliferative neoplasms (MPN):

Blastic plasmacytoid dendritic cell neoplasm (BPDCN):

Key distinction: TdT + CD19 + CD10 = B-ALL; MPO + CD13/33 + Auer rods = AML; co-expression with strict criteria = MPAL.

Board pearl: A patient with known PV develops pancytopenia and circulating blasts — post-PV AML, dismal prognosis, transplant is the only curative option but outcomes remain poor.

Key Differentials — Non-Malignant Causes of Cytopenias and Blasts

— Pancytopenia with hypocellular marrow, no blasts, no dysplasia

— Causes: idiopathic, drugs (chloramphenicol, carbamazepine), viral (parvovirus, hepatitis), radiation

— Treatment: immunosuppression (ATG + cyclosporine) or transplant in young patients

— Can evolve to MDS/AML — long-term surveillance

— Pancytopenia with macrocytosis, hypersegmented neutrophils, high LDH, elevated indirect bilirubin

— Can mimic AML with marked anemia and bicytopenia

— Marrow shows megaloblastic changes, not blasts

— Resolves with vitamin replacement

— Can cause leukoerythroblastic smear with circulating immature cells ("left shift") — rarely true blasts >20%

— DIC may occur — distinguish from APL by absence of promyelocytes with Auer rods

— Treat infection; cytopenias improve

— Fever, splenomegaly, bicytopenia, ferritin >500 (often >10,000), hypertriglyceridemia, hypofibrinogenemia, hemophagocytosis in marrow

— Can be triggered by infection (EBV), malignancy, autoimmune

— Treat per HLH-94 protocol (etoposide, dexamethasone)

— Methotrexate, chemotherapy, sulfa drugs, propylthiouracil, clozapine

— Time course matches drug exposure; marrow shows hypocellularity without blasts

— Parvovirus B19 → pure red cell aplasia, "giant pronormoblasts"

— HIV, EBV, CMV can cause cytopenias

— Hepatitis-associated aplastic anemia

— Hemolysis, thrombosis, cytopenias — flow cytometry CD55/CD59 deficient

— Associated with aplastic anemia and AML evolution

Aplastic anemia:

Severe B12 or folate deficiency:

Severe sepsis / overwhelming infection:

Hemophagocytic lymphohistiocytosis (HLH):

Drug-induced bone marrow suppression:

Viral infections with marrow effect:

Paroxysmal nocturnal hemoglobinuria (PNH):

Key distinction: Pancytopenia + macrocytosis + hypersegmented neutrophils + low B12 mimics AML but the marrow shows megaloblastic erythropoiesis with <5% blasts — treat with B12, not chemotherapy. Always check B12/folate before bone marrow biopsy in elderly pancytopenia.

Secondary Prevention, Discharge Planning, Long-Term Surveillance

— Discharge after count recovery (ANC >500, platelets stable) and afebrile

— Central line care education or removal

— Medication reconciliation: continue prophylaxis until counts robust

— Anti-infective prophylaxis: acyclovir (HSV/VZV), posaconazole (mold-active antifungal), TMP-SMX or atovaquone for PJP if on venetoclax/HMAs or post-transplant

— Avoid live vaccines until immune recovery

— Re-admit for each HiDAC consolidation cycle (typically 5–7 day inpatient + count recovery monitoring)

— Track cumulative anthracycline dose

— HLA typing, donor search initiated at diagnosis

— Pre-transplant evaluation: PFTs, echo, dental, ID screening

— Conditioning regimen choice (myeloablative vs. reduced-intensity) based on age, fitness, disease status

— CBC monthly first year, then less frequently

— Bone marrow biopsy at end of consolidation and as clinically indicated

— Measurable residual disease (MRD) monitoring by flow or molecular (NPM1, CBF transcripts) — rising MRD predicts relapse

— Surveillance for late effects: cardiac (echo for anthracycline exposure), endocrine, second malignancies

— Nutritional counseling — neutropenic diet during therapy (limited evidence but standard)

— Hand hygiene, mask use during nadirs

— Smoking cessation, alcohol moderation

— Mental health screening — depression and anxiety are common

— Survivorship clinic referral after CR1

— Inactivated vaccines per CDC immunocompromised schedule

— Live vaccines (MMR, VZV) only after 24 months and off immunosuppression with no GVHD

Post-induction discharge planning:

Consolidation cycle scheduling:

Transplant preparation (if applicable):

Long-term monitoring after CR:

Lifestyle and supportive care:

Vaccinations (after immune recovery, typically ≥6–12 months post-transplant):

Step 3 management: AML patient 1 year post-7+3 + HiDAC consolidation, in CR — surveillance plan is CBC every 1–3 months, marrow biopsy if cytopenias recur or molecular MRD rises, echo every 1–2 years given anthracycline exposure, and routine cancer screening per age-appropriate guidelines.

Board pearl: Rising NPM1 or RUNX1-RUNX1T1 transcript by RT-PCR signals molecular relapse weeks to months before hematologic relapse — pre-emptive treatment improves outcomes.

Follow-Up, Monitoring Parameters, Counseling

— CBC with differential daily

— Chemistry, magnesium, phosphorus daily; q6–12h during TLS risk

— Coags daily (more frequent in APL until DIC resolves)

— Fever curve, blood culture review

— Daily exam: mucositis grade, line site, abdominal exam (typhlitis), neuro exam (cerebellar, mental status)

— Strict I/O, daily weights

— Assesses early response

— Hypocellular with <5% residual blasts → await recovery

— Persistent disease (>10–15% blasts) → consider re-induction

— Marrow biopsy + flow + cytogenetics + MRD

— Complete remission: <5% blasts, ANC >1000, platelets >100k

— CRi (incomplete count recovery), MLFS (morphologic leukemia-free state) — partial responses with different prognostic weight

— Weekly for first month after discharge: CBC, CMP, exam

— Every 2 weeks during consolidation cycles, then monthly

— MRD assessment after each consolidation and pre-transplant if applicable

— Realistic prognosis discussion based on risk category

— Signs of relapse: fatigue, bleeding, fevers, bone pain

— Infection precautions during neutropenia at home (avoid sick contacts, crowds, raw/undercooked food per institutional guidance)

— Fertility implications and contraception

— Financial toxicity — social work and patient navigator referrals

— Support groups (LLS, Be The Match)

— Echo at end of therapy, then per cumulative anthracycline dose and symptoms

— Heart failure surveillance lifelong for patients with high cumulative anthracycline exposure

Inpatient monitoring during induction:

Day 14 marrow:

End-of-induction assessment (~day 28–35):

Outpatient follow-up after induction:

Counseling points for patient and family:

Cardio-oncology follow-up:

Key distinction: CR vs. CRi vs. MLFS — only true CR with full count recovery is associated with the best outcomes; CRi still allows proceeding to consolidation but with increased toxicity risk.

Step 3 management: A patient develops dyspnea 8 months post–7+3 with cumulative daunorubicin 360 mg/m² — order echo to evaluate for anthracycline cardiomyopathy and start GDMT (ACEi/ARB, beta-blocker) if EF reduced, with cardio-oncology referral.

Ethical, Legal, and Patient Safety Considerations

— Disclose realistic survival expectations by risk category (favorable ~60–70% cure with chemo ± transplant; adverse much lower)

— Discuss induction mortality (~5–10% in fit younger; up to 15–20% in older patients)

— Document discussion of alternatives, including palliative-only approach as a valid choice

— Use teach-back; involve interpreters for limited English proficiency

— Patients with leukostasis, sepsis, or severe encephalopathy may lack capacity

— Identify surrogate per state hierarchy; honor advance directives

— Reassess capacity as clinical state changes — capacity is decision-specific and dynamic

— Ethical obligation to offer fertility preservation discussion before chemotherapy for reproductive-age patients, even if urgent

— Document refusal or acceptance

— Special considerations for adolescents — assent + parental consent

— Early palliative care consultation improves outcomes and quality of life

— Avoid framing palliative care as "giving up"

— Re-address goals at relapse, refractory disease, and major decision points

— Highest-risk handoffs: ED to oncology floor, floor to ICU, hospital to home post-discharge, transfer to outside facility

— Use structured handoff (SBAR/IPASS) including current cytopenia trajectory, infection workup status, anticipated complications

— Discharge: ensure follow-up appointment scheduled, prescriptions filled (oral chemo, antimicrobials), patient understands return precautions

— Intrathecal vincristine = fatal (vincristine is IV only) — applies to ALL but a high-yield safety pearl in any leukemia context

— Right drug, right dose, right route — chemotherapy double-check protocols

— Tumor lysis prophylaxis omission → preventable AKI/death

— Therapy-related AML may warrant reporting to cancer registries; benzene exposure may trigger occupational health/OSHA reporting

— Disparities in access to transplant — refer early, advocate for insurance authorization

— Clinical trial offering is ethically encouraged, especially for adverse-risk and relapsed disease

Informed consent for induction:

Capacity and surrogate decision-making:

Fertility counseling:

Goals-of-care and palliative integration:

Transition-of-care safety:

Patient safety / never events:

Mandatory reporting:

Health systems and equity:

Board pearl: A 78-year-old with adverse-risk AML declines chemotherapy in favor of comfort-focused care — this is autonomous, informed refusal, and the correct response is to consult palliative care and respect the decision, not pursue ethics committee or attempt to override.

High-Yield Associations and Rapid-Fire Facts

— t(15;17) PML-RARA → APL, DIC, faggot cells, treat with ATRA + arsenic

— t(8;21) RUNX1-RUNX1T1 → CBF-AML, favorable, sometimes chloromas

— inv(16)/t(16;16) CBFB-MYH11 → favorable, eosinophilic component (M4eo)

— t(9;11) KMT2A-MLLT3 → monocytic, intermediate

— Complex karyotype / monosomy 5 or 7 / 17p del / TP53 → adverse

— Therapy-related: alkylators → 5q–/–7 with long latency; topo II inhibitors → 11q23 (KMT2A) short latency

— FLT3-ITD/TKD → midostaurin (newly diagnosed), gilteritinib (R/R), quizartinib (ITD)

— IDH1 → ivosidenib; IDH2 → enasidenib

— CD33 → gemtuzumab ozogamicin

— BCL2 dependence → venetoclax

— Auer rods = AML (any subtype but classic in M3)

— Faggot cells = APL

— Cup-like nuclei = NPM1-mutated AML, often FLT3-ITD co-mutated

— Monoblasts with folded "kidney-shaped" nuclei = M5

— Down syndrome → M7 megakaryoblastic (children); also ALL

— Fanconi anemia → AML in young adults

— Bloom, Li-Fraumeni, ataxia-telangiectasia → various leukemias

— Germline DDX41, RUNX1, CEBPA, GATA2 → familial MDS/AML

— Cytarabine → cerebellar toxicity, conjunctivitis

— Anthracyclines → cardiotoxicity (DOX > daunorubicin > idarubicin > epirubicin > mitoxantrone in cumulative risk profile)

— ATRA → differentiation syndrome, pseudotumor cerebri

— Arsenic → QT prolongation, hepatotoxicity

— Venetoclax → TLS, profound neutropenia; CYP3A interactions

— Gemtuzumab → veno-occlusive disease

— APL → ATRA before genetics confirm

— Leukostasis → hydroxyurea + leukapheresis, avoid pRBC

— TLS → rasburicase, IVF

— Neutropenic fever → empiric antibiotics within 1 hour

Cytogenetic-clinical pairings:

Mutation-targeted therapy pairings:

Morphology pearls:

Syndrome associations:

Drug toxicities — rapid fire:

Emergencies / "act now":

Board pearl: NPM1 mutation without FLT3-ITD in normal-karyotype AML = favorable risk; NPM1 mutated with FLT3-ITD high allelic ratio = intermediate; FLT3-ITD without NPM1 = adverse. Same gene, different partners, different prognoses.

Board Question Stem Patterns

— "55-year-old with fatigue, gingival bleeding, petechiae; WBC 2.5, plt 18, fibrinogen 90, D-dimer elevated, INR 1.8. Smear shows promyelocytes with multiple Auer rods..."

— Answer: Start ATRA immediately, support with platelets, cryoprecipitate, FFP. Confirm with PML-RARA. Do NOT delay ATRA awaiting results.

— "Newly diagnosed AML, WBC 180k, dyspneic with hypoxia and confusion..."

— Answer: Hydroxyurea ± leukapheresis, IV hydration, AVOID pRBC transfusion, urgent induction. Distractor: "transfuse pRBC to Hgb 10" is wrong.

— Rising K, phos, uric acid, falling Ca, AKI during induction

— Answer: Rasburicase, aggressive IV fluids, monitor electrolytes q6h; hemodialysis if refractory

— "Patient receiving HiDAC develops new ataxia and dysmetria"

— Answer: Hold cytarabine immediately; do not give next dose. Distractor: "reduce dose" — wrong, must hold.

— "72-year-old with new AML, ECOG 1, EF 60%, no comorbidities, intermediate-risk cytogenetics"

— Answer: Intensive induction (7+3); consider HSCT in CR1

— Same stem with ECOG 3, EF 30%, CKD → venetoclax + azacitidine

— "Newly diagnosed AML with FLT3-ITD positive"

— Answer: 7+3 + midostaurin; consider transplant in CR1

— APL patient on day 5 of ATRA develops fever, dyspnea, weight gain, infiltrates

— Answer: Dexamethasone 10 mg IV BID; continue ATRA unless life-threatening

— Patient post-induction with fever, ANC 200

— Answer: Empiric cefepime (or pip-tazo/meropenem) within 1 hour; cultures first but do not delay antibiotics

— "Adverse-risk AML in CR1 with matched sibling"

— Answer: Allogeneic HSCT in CR1

— Pancytopenia + macrocytosis + hypersegs + low B12 → B12 deficiency, not AML

Pattern 1 — The APL stem:

Pattern 2 — The leukostasis stem:

Pattern 3 — The TLS stem:

Pattern 4 — The cerebellar toxicity stem:

Pattern 5 — The fit-vs-unfit choice:

Pattern 6 — Targeted therapy add-on:

Pattern 7 — Differentiation syndrome:

Pattern 8 — Neutropenic fever:

Pattern 9 — Post-CR planning:

Pattern 10 — Mimic recognition:

Step 3 management: The recurring theme — Step 3 stems test you on the immediate next action, then on the disposition and follow-up. Always think: stabilize → confirm → risk-stratify → treat → plan transitions.

One-Line Recap

AML is a marrow-failure emergency where the first 24 hours center on recognizing pancytopenia with blasts, ruling in or out APL by checking fibrinogen and the smear, starting tumor-lysis prophylaxis, and risk-stratifying with cytogenetics/molecular testing — because the choice between 7+3 (± midostaurin), venetoclax + azacitidine, or ATRA + arsenic, and the decision to pursue allogeneic transplant in CR1, all flow directly from those data.

Recognize: Pancytopenia + circulating blasts + Auer rods in an adult; check fibrinogen/D-dimer in everyone — APL kills early from DIC, and ATRA is empiric before genetics return.

Risk-stratify: ELN 2022 categories (favorable, intermediate, adverse) driven by cytogenetics + NPM1/FLT3/TP53/CEBPA/RUNX1/ASXL1 mutations; favorable goes to high-dose cytarabine consolidation, intermediate/adverse fit patients go to allo-HSCT in CR1.

Treat by fitness: Fit → 7+3 (add midostaurin for FLT3, gemtuzumab for CBF/CD33, CPX-351 for t-AML/AML-MRC); unfit → venetoclax + azacitidine as new standard. APL = ATRA + arsenic, chemo-free in low/intermediate risk, >90% cure.

Manage complications: Neutropenic fever → broad-spectrum antibiotics within 1 hour; leukostasis → hydroxyurea + leukapheresis, no pRBC; TLS → rasburicase + fluids; differentiation syndrome → dexamethasone, continue ATRA.

Board pearl: When the stem includes DIC + promyelocytes, give ATRA before the karyotype — this single decision saves the most lives on both the exam and in real practice.