N. Boeckx MD, PhD

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)

Tyrosine kinase inhibitor discontinuation in patients with chronic myelogenous leukaemia: A retrospective study and review of the literature

ABSTRACT

BACKGROUND: Tyrosine kinase inhibitors (TKIs) have improved the survival of patients with chronic myeloid leukaemia (CML). TKIs can be successfully discontinued in some CML patients who have achieved a stable deep molecular response.

OBJECTIVE: The purpose of this article is twofold. On the one hand, this review provides an overview of current use and discontinuation of TKIs in patients with CML. On the other hand, we retrospectively investigated the use and possible discontinuation of TKIs in a specific patient population with CML at the University Hospital of Leuven.

METHODS: A literature search was carried out in May 2019 to identify all relevant articles. Articles were searched on PubMed, Embase, Web of Science and Cochrane Library. Additionally, the articles found in the reference list were used.

RESULTS: This review included ten articles (two on imatinib, four on dasatinib, four on nilotinib), with 970 patients. Treatment free remission (TFR) ratio varied from 41–68% after one year. One study published the results of TFR after three years. In UZ Leuven, the TFR ratio was 60% after 106 weeks.

CONCLUSION: Tyrosine kinase inhibitor (TKI) therapy can be safely terminated in selected patient groups. About half of the patients retain the molecular remission after discontinuation of TKI therapy.

(BELG J HEMATOL 2020;12(2):52-8)

P.16 Malignant invasion of the cerebrospinal fluid in patients with a haematological malignancy: a single center retrospective study

P.17 Feasibility of next generation flow for minimal residual disease in multiple myeloma on a BD FACS Lyric flowcytometer

P.40 Impact of the WPC channel of the Sysmex XN-9100 system in the reduction of false positive flags in paediatric samples

Management of severe aplastic anaemia

SUMMARY

Aplastic anaemia is a rare condition characterised by pancytopenia and bone marrow hypocellularity and caused by the immune-mediated destruction of the haematopoietic precursors. The early complications are related to cytopaenias with infections being the major cause of morbi-mortality. The main long-term issue is clonal evolution to myelodysplastic syndrome or acute leukaemia. The diagnosis relies on exclusion of other causes of pancytopenia and characteristic pathologic findings. Severity is stratified according to peripheral blood counts. Nowadays, the survival of treated patients reaches 80–90%. The treatment of the severe form of aplastic anaemia consists on haematopoietic stem cell transplantation in eligible patients and immunosuppressive therapy in non-transplant candidates. Supportive therapy is an option in frail and/or elderly patients. Here, we define and briefly review the pathogenesis of aplastic anaemia. We propose a diagnostic and therapeutic strategy based on existing literature and experts’ recommendations. We finally report three cases illustrating particular clinical associations with pregnancy, hepatitis and paroxysmal nocturnal haemoglobinuria.

(BELG J HEMATOL 2018;9(3):76–85)

PP02 Monocentric retrospective study of 138 therapy-related myeloid neoplasms