The year 2021 was rich in innovations in regard to both malignant and benign hematological diseases, with the most relevant of which discussed below.

- In recent years, the prognosis of multiple myeloma has been greatly improved, yet the disease remains as yet incurable. Current strategies aim to achieve optimal disease control at diagnosis using four-drug regimens designed to delay relapse, while in relapsed patients, innovative alternatives like immunotherapy are being employed to effectively re-arm the immune system, and this represents a real hope for patients suffering from this chronic disease.

- The management of chronic myeloid leukemia is still evolving. Since 2001, tyrosine kinase inhibitors have revolutionized its prognosis, but they are also responsible for toxicities. One of the current therapeutic goals is to achieve a sufficiently deep and prolonged response, thereby enabling tyrosine kinase inhibitors to be discontinued and remission maintained.

- Myelofibrosis is a myeloproliferative neoplasm with poor prognosis. The only curative treatment available to date is peripheral stem cell allograft, which can be applied at least for some patients. New therapeutic agents are currently being investigated, which are highly promising not only on account of their efficacy on symptoms and splenomegaly, but also for their potential anti-fibrotic and reducing effect on the mutated clone. Certain agents are in clinical assays in combination with JAK2 inhibitors.

- Several recent studies have suggested that CAR-Ts were likely to emerge as the second-line treatment of choice for patients suffering from aggressive lymphomas, while secondarily reducing the number of autologous stem cell transplants.

- Patients with acute myeloid leukemia and TP53-mutated myelodysplastic syndromes still represent a challenging population to treat with low and only short-lived response rates. The advent of APR-246, which restores TP53 activity, is likely to increase the number of responders among these very high-risk patients.

- Beyond its well-known involvement in heparin thrombocytopenia, platelet factor 4 (PF4) plays a major role in the very rarely observed thrombosis with thrombocytopenia occurring in association with COVID-19 adenoviral vector vaccines. Inhibition of FXI is expected to emerge as a promising anticoagulation strategy with reduced bleeding risk, while induction of antithrombin deficiency by interfering RNA is likely to prevent bleeding in hemophilia A and B patients, either with and without inhibitors.

- Concerning the management of immune thrombocytopenic purpura, targeted therapies are currently being favored owing to their lower toxicity and individualized platelet count targets.

In 2021, a new wind of creativity and dynamism blew through the department owing to the arrival of two new medical staff members. In the special hematology laboratory, the diagnostic protocols in morphology and flow cytometry were reviewed, with the recommendations for the research and interpretation of schistocytes updated accordingly. The search for short telomere syndromes based on the Flow-Fish technique has taken off, with increasingly numerous clinical indications, including pulmonary fibrosis, bone marrow aplasia, and several others. The research outcomes are critical for both optimally managing patients and genetic counseling of families.

High-throughput sequencing (NGS) has been revolutionizing routine medical practice in hemato-oncology for several years now. This targeted sequencing has enabled the search for markers with diagnostic, prognostic, or therapeutic value, thereby opening the way to a more personalized medicine. The hematology molecular biology laboratory has kept on developing this technology. As a result, NGS can now be carried out there for all the hematological-oncological pathologies provided for in the RIZIV-INAMI agreement. Efforts are also being focused on further developing the RNA sequencing technique recommended since 1/1/2022 for two onco-hematological pathologies.

The HLA system plays a central role in human immunity, whereas it also constitutes a major obstacle to organ transplantation. The involvement of anti-HLA antibodies in early and late rejection is currently indisputable. Given this context, the leuko-platelet immunology laboratory implemented a new test for identifying clinically more relevant anti-HLA antibodies in order to facilitate graft allocation.

COVID-19 has not spared the hematological biology department, playing spoilsport at the Blood Bank. Indeed, not only were the transfusion needs of certain Sars-CoV-2-infected patients rather substantial, but the erythrocyte immunology laboratory was confronted with detecting virus-induced anti-erythrocyte autoantibodies, thereby interfering with routine tests while rendering the search for compatible blood at times even more complex.

One of the Transfusion Committee’s objectives in 2021 was to further develop "Patient Blood Management" (PBM) within the various departments at Cliniques universitaires Saint-Luc. The neonatology department was chosen to be the pilot department, with the intention to work on the second PBM pillar, meaning to minimize blood loss by reducing blood sampling in infants. A decision-making flowchart was established and presented to the pediatric medical and nursing teams prior to being implemented.

These different initiatives have been made possible only through the work of the different departmental teams, at all times seeking to fully respect the patient while offering them optimal care.