What is the role of Next-Generation Sequencing (NGS) in evaluating dysplastic bone marrow?

From the Guidelines

Next-generation sequencing (NGS) is a crucial tool in evaluating dysplastic bone marrow, providing comprehensive genetic analysis that helps diagnose, classify, and manage myelodysplastic syndromes (MDS) and related disorders, as evident from the study by Tobiasson and Kittang 1. The role of NGS in MDS is multifaceted, including:

• Diagnostic purposes to discriminate between MDS and other diseases
• Classification, such as identifying SF3B1 mutation for ring sideroblast anaemia subgroups
• Identification of patients suitable for targeted therapy, like IDH1/2 inhibitors
• Prognostication, where specific mutations are associated with inferior or superior prognosis
• Monitoring patients for progression or treatment failure Key genes that can be detected by NGS in MDS include TET2, ASXL1, DNMT3A, SF3B1, SRSF2, and TP53, which may not be identifiable through conventional cytogenetic testing, as discussed in the study by Tobiasson and Kittang 1. NGS results provide prognostic information that helps stratify patients into risk categories, guiding treatment decisions between supportive care, hypomethylating agents like azacitidine or decitabine, immunomodulatory drugs, or consideration for stem cell transplantation, as mentioned in the study by Tobiasson and Kittang 1. The presence of certain mutations, like SF3B1, may predict response to specific therapies, while others, such as TP53 mutations, indicate poor prognosis and may warrant more aggressive treatment approaches, as highlighted in the study by Tobiasson and Kittang 1. For optimal clinical utility, NGS testing should be performed on bone marrow samples at diagnosis and interpreted in conjunction with morphologic, cytogenetic, and clinical findings by a multidisciplinary team, as recommended by Tobiasson and Kittang 1. Some of the key points to consider when using NGS in MDS include:
• The IPSS/IPSS-R scoring system is a cornerstone in risk assessment, but NGS data add a new dimension of complexity to the risk assessment
• Certain mutations, such as TP53, RUNX1, and U2AF1, are strongly associated with progressive disease
• NGS contributes most to clinical decision-making for patients considered to be low risk based on the risk scores
• The combination of complex karyotype and TP53 or RAS-pathway mutations in patients with MDS/MPN disease indicates a very poor prognosis even after SCT, as discussed in the study by Tobiasson and Kittang 1.

From the Research

Role of Next-Generation Sequencing (NGS) in Evaluating Dysplastic Bone Marrow

• NGS plays a significant role in evaluating dysplastic bone marrow by providing molecular profiling, which can predict outcomes and identify patients who are unlikely to benefit from certain treatments 2.
• The technology can detect mutations in genes such as TP53, ASXL1, TET2, DNMT3A, and SRSF2, which are commonly found in myelodysplastic syndromes (MDS) 2.
• NGS can also provide prognostic value and support a confident or tentative histopathological diagnosis in patients with cytopenia suspected of MDS 3.
• The use of NGS in routine diagnostics and management of patients with cytopenia has been shown to have a diagnostic impact and provide prognostic value 3.

Applications of NGS in Hematologic Neoplasms

• NGS can be used to analyze peripheral blood and bone marrow samples, providing a minimally invasive screening tool for hematologic neoplasms 4.
• The concordance between peripheral blood and bone marrow NGS results has been shown to be high, with a kappa coefficient of 0.794, indicating a reliable tool for mutational analysis 4.
• NGS can also be used to track the dynamics of donor-derived cell-free DNA, providing noninvasive allograft monitoring 5.
• The technology has been applied in various clinical settings, including histocompatibility and transplantation, to achieve unambiguous human leukocyte antigen genotyping and to detect minimal residual disease following allogeneic stem cell transplantation 5.

Limitations and Future Directions

• Despite the enthusiasm about NGS, there are limitations to consider, such as coverage and accuracy of <100%, resulting in missing variants and false positive findings 6.
• There is an urgent need to define standards for NGS with respect to run quality and variant interpretation, as well as mechanisms of quality control 6.
• Further studies are needed to fully explore the potential of NGS in evaluating dysplastic bone marrow and to establish its role in clinical practice 2, 3, 4, 5.