Morphology, cytogenetics and classification of MDS

Area of Science:

• Hematology
• Oncology
• Pathology

Background:

• Myelodysplastic syndromes (MDS) are heterogeneous bone marrow disorders.
• Diagnosis is challenging in early MDS, particularly with uncertain cytopenias or dysplasia.
• Cytomorphological, genetic, epigenetic, and immune factors influence MDS pathogenesis.

Purpose of the Study:

• To provide recommendations for stepwise diagnosis of MDS.
• To detail diagnostic criteria for dysplasia in all cell lineages.
• To discuss the role of cytogenetics, molecular abnormalities, and histopathology in MDS diagnosis and prognosis.

Main Methods:

• Review of diagnostic criteria and classification systems (FAB to WHO).
• Analysis of cytomorphological findings in peripheral blood and bone marrow.
• Evaluation of cytogenetic abnormalities, including FISH analysis and the IPSS-R scoring system.
• Discussion of histopathology's diagnostic and prognostic value.

Main Results:

• Early MDS diagnosis is difficult, requiring careful evaluation of dysplasia and cytopenias.
• Cytogenetic abnormalities are found in up to 70% of MDS patients, impacting diagnosis and prognosis.
• Histopathology is valuable in specific cases (hypoplasia, fibrosis, TP53 mutations).
• FISH analysis aids chromosome assessment and peripheral blood monitoring.

Conclusions:

• Accurate MDS diagnosis relies on integrating cytomorphology, genetics, and histopathology.
• The IPSS-R scoring system incorporates cytogenetic data for improved prognosis.
• Evolving classification systems aim to better capture MDS heterogeneity and dynamics.