Cytogenetic and molecular studies in haematological malignancy
Karyotype, FISH, PCR and NGS: what each test finds, how to read the nomenclature and a variant allele fraction, the lesions that define and risk-stratify CML, APL, AML, MPN, CLL, lymphoma, myeloma and MDS, and the sample and interpretation traps.
Tier 2Medical sciences concept
Written with AI assistance and fact-checked against the sources below. For exam study, not clinical decisions. How notes are made
At a glance
- Four main tools: karyotype, FISH, PCR and next-generation sequencing (NGS). They answer different questions and are often all sent on one marrow.
- Genetics now defines many diseases (WHO 2022, ICC 2022), sets risk (ELN 2022 for AML, IMS/IMWG 2025 for myeloma) and picks targeted drugs (FLT3, BCR::ABL1, IDH, TP53 status in CLL).
- Send marrow or blood fresh, unfixed, in heparin (cytogenetics) or EDTA (molecular). A formalin-fixed trephine can still give FISH but not a karyotype.
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Sources
- Diagnosis and management of AML in adults: 2022 recommendations from an international expert panel on behalf of the ELNDöhner H et al., Blood 2022;140:1345-77, 2022
- Genetic risk classification for adults with AML receiving less-intensive therapies: the 2024 ELN recommendationsDöhner H et al., Blood 2024, 2024
- iwCLL guidelines for diagnosis, indications for treatment, response assessment, and supportive management of CLLHallek M et al., Blood 2018;131:2745-60, 2018 (no newer iwCLL edition found November 2026)
- The 5th edition of the World Health Organization Classification of Haematolymphoid Tumours: Myeloid and Histiocytic/Dendritic NeoplasmsKhoury JD et al., Leukemia 2022;36:1703-19, 2022
- The 5th edition of the World Health Organization Classification of Haematolymphoid Tumours: Lymphoid NeoplasmsAlaggio R et al., Leukemia 2022;36:1720-48, 2022
- International Consensus Classification of Myeloid Neoplasms and Acute LeukemiasArber DA et al., Blood 2022;140:1200-28, 2022
- International Myeloma Society/International Myeloma Working Group consensus recommendations on the definition of high-risk multiple myelomaAvet-Loiseau H et al., J Clin Oncol 2025;43:2739-51, 2025
- 2025 European LeukemiaNet recommendations for the management of chronic myeloid leukemiaApperley JF et al., Leukemia 2025;39:1797-1813, 2025
- Schedule of Pharmaceutical Benefits (midostaurin, gilteritinib, tyrosine kinase inhibitors)AU/NZAustralian Government Department of Health, Disability and Ageing
- Last updated
- 14 November 2026
What changed
- 14 November 2026 Turnstile bot check on sign-in and signed-out feedback