L. Michaux MD, PhD

Current advances in cytogenomics – Implementation of Optical Genome Mapping into diagnostic workflows for haematological neoplasms: A Belgian Cytogenomic Group for Haemato-Oncology (BCG-HO) position statement

SUMMARY

Genomic abnormalities play an increasingly important role in prognostication and classification of haematological malignancies (HM), as evidenced by their continual integration into updated classification and risk assessment models. Optical Genome Mapping (OGM) is a relatively new high-resolution technology that offers novel opportunities to assess chromosome abnormalities, increasing the detection yield of clinically relevant abnormalities and allowing rationalisation of diagnostic pathways by abrogating the need for multiple complementary tests. Furthermore, it could streamline laboratory’s technical pipelines, avoiding the need for multiple disease specific workflows. Given these findings, OGM is currently being implemented into the diagnostic workflow, as a first line test, by numerous laboratories worldwide and is being validated with view to implementation in many more, including Belgium. Here we propose recommendations for implementation of OGM testing in the routine diagnostic workup of HM.

(BELG J HEMATOL 2024;15(6):233–7)

FLT3 mutation in AML, which test for which patients?

SUMMARY

Genetic analysis of acute myeloid leukaemia (AML) has identified multiple genetic markers of prognostic significance that can be used for risk stratification of patients at diagnosis. Of these, mutations of the FMS-like tyrosine kinase 3 receptor gene (FLT3) are one of the most important. FLT3 mutations are found in 30% of AML cases overall. They are present in different AML entities and across the cytogenetic subgroups, the most common being in AML patients with a normal karyotype. They are generally considered poor prognostic indicators although the prognostic impact is influenced by the type of FLT3 mutation as well as the co-existence of other mutations and cytogenetic background. FLT3 encodes a tyrosine kinase receptor that can be targeted by tyrosine kinase inhibitors and their introduction into treatment protocols has significantly improved the prognosis of these patients with a prior dismal outcome. Given the poor prognosis, and availability of targeted treatment, FLT3 testing is recommended for all new AML cases at diagnosis with the results available within 72 hours for determination of treatment strategies. This short turnaround time (TAT) is challenging for diagnostic laboratories and affects the method of testing. Herein, we review the current recommendations for FLT3 testing in AML, discuss the different available methods for FLT3 mutation testing, and highlight considerations for AML clinicians when faced with AML patients at diagnosis or at a relapsing stage.

(BELG J HEMATOL 2022;13(2):59–64)

Advanced systemic mastocytosis: An uncommon cause of chronic diarrhoea and weight loss

SUMMARY

Introduction: Advanced systemic mastocytosis is a rare myeloproliferative disorder of mast cells, damaging the function of various organs and tissues. The diagnosis can be challenging due to its protean manifestations and rareness. Treatment options have improved over the last years. Currently, avapritinib, a novel tyrosine kinase inhibitor with activity against p.D816V mutated KIT, is under investigation.

Case: We report a case of a 64-year old man with chronic diarrhoea, fatigue, weight loss and ascites with hepatomegaly, developing an upper gastro-intestinal bleeding with multiple duodenal ulcers. Diagnostic work-up revealed hepatosplenomegaly and portal hypertension, a vertebral compression fracture and multiple ¹⁸F-FDG avid supra- and infradiaphragmatic lymph nodes and bone marrow. Based on the 2016 WHO criteria of systemic mastocytosis, and a concomitant chronic myelomonocytic leukaemia, the diagnosis of an aggressive systemic mastocytosis with an associated haematological neoplasm was made. The patient was consecutively treated with midostaurin, cladribine and avapritinib, the latter inducing a complete biochemical and molecular response.

Conclusion: This case illustrates the challenging clinical presentation of systemic mastocytosis. A deep response to avapritinib was observed despite prior use of midostaurin and cladribine, underlining its promise in advanced systemic mastocytosis.

(BELG J HEMATOL 2022;13(2):84–91)

EBV-induced double hit transformation of splenic (marginal zone) lymphoma, in a patient with a chronic Hepatitis B virus hepatitis

SUMMARY

We report a case of an EBV-induced large-cell transformation of a splenic marginal zone lymphoma in an 81-year-old female with a simultaneous finding of hepatitis B viral infection.

(BELG J HEMATOL 2021;12(6):275-9)

Practical management of multiple myeloma: Update 2020

SUMMARY

With the introduction of immunomodulatory drugs, proteasome inhibitors and anti-CD38 monoclonal anti-bodies, major improvements have been achieved in the treatment and outcome of multiple myeloma (MM). Different treatment combinations are now in use and other therapies are being developed. This rapidly changing therapeutic landscape urges for an update on practical guidelines. Based on an extensive review of the recent literature, we propose recommendations on myeloma management, to be used by haematologists as a reference for daily practice.

(BELG J HEMATOL 2020;11(8):357-75)

Practical management of multiple myeloma: Update 2020

SUMMARY

With the introduction of immunomodulatory drugs, proteasome inhibitors and anti-CD38 monoclonal antibodies, major improvements have been achieved in the treatment and outcome of multiple myeloma (MM). Different treatment combinations are now in use and other therapies are being developed. This rapidly changing therapeutic landscape urges for an update on practical guidelines. Based on an extensive review of the recent literature, we propose recommendations on myeloma management, to be used by haematologists as a reference for daily practice.

(BELG J HEMATOL 2020;11(7):286-304)

Diagnostic testing in myeloid malignancies by next-generation sequencing: recommendations from the Commission Personalised Medicine

SUMMARY

Molecular diagnostics have an increasing impact on diagnosis, risk stratification and targeted treatment in haemato-oncology. In the framework of a pilot study for the implementation of next-generation sequencing in the Belgian healthcare system, the Commission of Personalised Medicine was founded to give professional and evidence-based advice on the molecular analysis in haemato-oncology. This paper describes its recommendations for NGS analysis in myeloid malignancies. In addition, the minimally required set of genes that must be analysed is defined and algorithms for molecular workflow in myeloid malignancies are proposed.

(BELG J HEMATOL 2019;10(6):241–9)