Maria Stefania De Propris

Chronic myeloid leukemia (CML) represents a paradigm of targeted therapy, driven by the BCR::ABL1 fusion kinase. Over the past four decades, therapeutic strategies have evolved from early molecular targeting approaches and interferon-α to tyrosine kinase inhibitors (TKIs), dramatically improving survival and transforming CML into a largely controllable disease. To provide a comprehensive overview of this evolution, we conducted a narrative literature search across the PubMed and Embase databases, selecting peer-reviewed articles, international guidelines, and landmark clinical trials based on their historical and clinical relevance. Through this expert-driven synthesis, focusing on key milestones in CML therapy, including antisense strategies, interferon-based treatment, first-, second-, and third-generation TKIs, and the development of allosteric inhibitors, this paper analyzes current management strategies, treatment-free remission (TFR), and emerging therapies. The introduction of imatinib established proof of principle for oncogene-targeted therapy, leading to sustained survival improvements. Second- and third-generation TKIs further enhanced response depth and addressed resistance, including the T315I mutation. More recently, the development of the allosteric inhibitor asciminib introduced a novel mechanism of action and expanded therapeutic options for pretreated patients. Furthermore, the achievement of deep molecular responses has enabled TFR in approximately 40–60% of selected patients, redefining treatment goals toward functional cure. Emerging agents, including next-generation ATP-competitive and allosteric inhibitors, are showing promising activity in resistant disease and may further improve outcomes. Thus, CML represents a unique model of translational oncology, demonstrating how mechanistic insight can drive therapeutic innovation. Future strategies will focus on increasing TFR rates, overcoming resistance, targeting leukemic stem cells, and improving global access to therapy and monitoring, with the ultimate aim of achieving functional cure in the majority of patients.

Background: Chronic myeloid leukemia (CML) is a paradigm of targeted therapy, driven by the BCR::ABL1 fusion kinase. Over the past four decades, therapeutic strategies have evolved from early molecular targeting approaches and interferon-α to tyrosine kinase inhibitors (TKIs), dramatically improving survival and transforming CML into a largely controllable disease. Methods: We performed a narrative review of the literature, focusing on key milestones in CML therapy, including antisense strategies, interferon-based treatment, first-, second-, and third-generation TKIs, and the development of allosteric inhibitors. Current management strategies, treatment-free remission (TFR), and emerging therapies were also analyzed. Results: The introduction of imatinib established proof of principle for oncogene-targeted therapy, leading to sustained survival improvements. Second- and third-generation TKIs further enhanced response depth and addressed resistance, including the T315I mutation. The development of the allosteric inhibitor asciminib introduced a novel mechanism of action and expanded therapeutic options for pretreated patients. Deep molecular responses have enabled TFR in approximately 40–60% of selected patients, redefining treatment goals toward functional cure. Emerging agents, including next-generation ATP-competitive and allosteric inhibitors, are showing promising activity in resistant disease and may further improve outcomes. Conclusions: CML represents a unique model of translational oncology, demonstrating how mechanistic insight can drive therapeutic innovation. Future strategies will focus on increasing TFR rates, overcoming resistance, targeting leukemic stem cells, and improving global access to therapy and monitoring, with the ultimate aim of achieving functional cure in the majority of patients.

Background: Discrimination between clonal and reactive cell proliferation is critical for the correct management of T-cell lymphocytosis. Multiparametric flow cytometry (MFC) represents a valuable tool, particularly because it allows to evaluate the T-cell receptor (TCR) Vβ repertoire to pinpoint eventual clonality in T-cell lymphocytosis. A restricted expansion of a single out of the 24 evaluable families or a “clonogram-off” pattern are highly suggestive of the presence of a clonal T-cell population. However, data available on the concordance between MFC TCR-Vβ repertoire and molecular analysis of TCR gene rearrangements, which is regarded as the gold standard for assessing T-cell clonality, are limited. Objective and methods: We performed a retrospective monocentric study including 307 patients referred to our center for lymphocytosis between 2003 and 2024. The aim of our study was to investigate the diagnostic accuracy of MFC TCR-Vβ repertoire analysis and to compare its performance with molecular analysis of TCR gene rearrangements, for the identification of T-cell clonality. Results: MFC TCR-Vβ repertoire analysis demonstrated a restricted expansion of a single Vβ family in 67.5% of cases, while clonality in the remaining 32.5% was inferred by a “clonogram-off” pattern. For 215 (70%) patients both MFC TCR-Vβ repertoire analysis and molecular analysis of TCR gene rearrangements were available, showing an absolute concordance (215 out of 215 cases, 100%) between the two methods. Conclusion: MFC TCR-Vβ repertoire analysis is a rapid, cheap, sensitive, and reliable tool to identify clonal T-cell lymphocytosis. It represents an absolute valid first-line diagnostic approach, and it should be included into the routinely laboratory work-up performed MFC analysis for peripheral lymphocytosis.

Background: Clonal mature B-cell lymphoproliferative disorders (B-LPDs) are a heterogeneous group of neoplasia characterized by the proliferation of mature B lymphocytes in the peripheral blood, bone marrow and/or lymphoid tissues. B-LPDs classification into different subtypes and their diagnosis are based on a multiparametric approach, however accurate diagnosis may be challenging, especially for cases of ambiguous interpretation. Multiparameter flow cytometry (MFC) represents an extensively used technique to detect the presence of different cellular lines in immunology and hematology. MFC results provide an essential contribution to B-LPDs diagnostic process, even more considering that panels are constantly integrating novel markers to improve diagnostic accuracy. Objectives: The aim was to evaluate the contributing role of MFC routinary studies analyzing the expression and the mean fluorescence intensity (MFI) of CD200, ROR1 and CD43 in various B-LPDs, to evaluate their usefulness in differential diagnosis of these diseases. Methods: We retrospectively evaluated a total of 2615 consecutive cases of newly samples (collected mostly from patients with lymphocytosis) analyzed by MFC carried out in B-LPDs diagnostic process referred to the Division of Hematology of ‘Sapienza’ University of Rome. We compared results of CD200, ROR1 and CD43 expression percentage and their MFI between different subtypes of B-LPDs. Results: In chronic lymphocytic leukemia (CLL) CD200, ROR1 and CD43 were always expressed with bright intensity. CLL samples presented CD200 expression and MFI [CD200%, mean: 100 (range, 24-100); positivity rate: 100%; MFI, mean = 168 (range, 10-1200)] and highly expressed statistically higher than mantle cell lymphoma (MCL) (p0.9). CD43 expression and MFI were significantly higher in CLL [CD43%, mean: 99 (range, 59-100); positivity rate: 100%; MFI, mean = 218 (range, 41-980)] than in MCL, vHCL, cHCL and all the others mature B-cell neoplasia (p<0.001). CD200 and CD43 expression and MFI were significantly higher in cHCL compared to vHCL. Among the others mature B-cell neoplasia, CD200 was variably expressed in follicular lymphoma (FL), marginal zone lymphoma (MZL), diffuse large B-cell lymphoma (DLBCL) and lymphoplasmacytic lymphoma (LPL). ROR1 and CD43 presented a very low expression percentage in this latter group, being mostly negative. Persistent polyclonal B-cell lymphocytosis (PPBL) resulted uniformly positive for CD200 and negative for ROR1 and CD43. Conclusions: Our data suggest that evaluation of CD200, ROR1 and CD43 antigens and their intensity of expression, along with commonly used markers in MFC routine panels for B-LPDs, might be extremely useful for a prompt diagnostic evaluation in the differential diagnosis of these diseases.

Background: B-lineage acute lymphoblastic leukemias (B-ALL) harboring the t(9;22)(q34;q11)/BCR::ABL1rearrangement, represent a category with previously dismal prognosis whose management and outcome dramatically changed thanks to the use of tyrosine kinase inhibitors (TKIs) usage and more recently full chemo-free approaches. The prompt identification of these cases represents an important clinical need. Objectives: We sought to identify an optimized cytofluorimetric diagnostic panel to predict the presence of Philadelphia chromosome (Ph) in B-ALLs cases by the introduction of CD146 in our multiparametric flow cytometry (MFC) panels. Methods: We prospectively evaluated a total of 245 cases of newly diagnosed B-ALLs with a CD146 positivity threshold >10% referred to the Division of Hematology of ‘Sapienza’ University of Rome. We compared results of CD146 expression percentage and its mean fluorescence intensity (MFI) between Ph+ ALLs, Ph-like ALLs and molecularly negative ALLs. Results: Seventy-nine of the 245 B-ALL cases (32%) did not present mutations at molecular testing, with 144/245 (59%) resulted Ph+ ALL and 19/245 (8%) Ph-like ALLs. Comparing the 3 groups we found that: Ph+ B-ALL were characterized by higher expression percentage of myeloid markers such as CD13, CD33 and CD66c and low expression of CD38; Ph+ B-ALL showed a higher CD146 expression percentage and MFI when compared with both molecular negative B-ALL and Ph-like ALLs; neither the mean percentage of CD146 expression neither CD146 MFI were statically different between molecular negative B-ALL and Ph-like ALLs. Conclusions: Our data demonstrate the association between CD146 expression and Ph+ B-ALLs. CD146 along with myeloid markers may help to identify a distinctive immunophenotypic pattern, useful for rapid identification in diagnostic routine of this subtype of B-ALLs that benefits from a specific therapeutic approach.

Background: Chimeric antigen receptor (CAR)-T cells represent a potentially curative strategy for patients with relapsed or refractory (R/R) B-cell malignancies. To elucidate a possible host immune activation following CAR-T-cell infusion, we investigated the effects of tisagenlecleucel administration on the patients’ immune populations in 25 patients with R/R diffuse large B-cell lymphoma (DLBCL) and B-lineage acute lymphoblastic leukemia (B-ALL). Methods: The modulation of CAR-T cells over time, the numeric changes, as well as the cytokine production capability of different lymphocyte populations and circulating cytokine levels, were analyzed. Results: Our results confirmed the ability of tisagenlecleucel to control the disease, with an overall response observed in 84.6% of DLBCL and in 91.7% of B-ALL patients at 1-month post-infusion, and showed that most patients who subsequently relapsed could undergo further treatment. Interestingly, we could document a significant increase in CD3⁺, CD4⁺, CD8⁺, and NK cells over time, as well as a decrease in Treg cells, and an increased IFNγ and TNFα production by T lymphocytes. Conclusions: Taken together, our results indicate that in patients with DLBCL and B-ALL, the administration of tisagenlecleucel is capable of inducing a marked and prolonged in vivo modulation/reshaping of the host immune system, both in children and adults.

Multiple myeloma (MM) is a plasma cell disorder that develops in the bone marrow (BM) and is characterized by uncontrolled proliferation and the ability to disseminate to different sites of the skeleton. Sialofucosylated structures, particularly Sialyl Lewis a/x (SLe^a/x), facilitate the homing of MM cells into the BM, leading to resistance to bortezomib in vivo. Platelets have been shown to play an important role in tumor metastasis. Platelets can bind to the surface of cancer cells, forming a “cloak” that protects them from the shear stress of the bloodstream and natural killer (NK) cell-mediated cytotoxicity. In this study, we showed that the presence of SLe^a/x induced a strong binding of MM cells to P-selectin, leading to specific and direct interactions with platelets, which could be inhibited by a P-selectin-blocking antibody. Importantly, platelets surrounded SLe^a/x-enriched MM cells, protecting them from NK cell-mediated cytotoxicity. The interactions between the platelets and MM cells were also detected in BM samples obtained from MM patients. Platelet binding to SLe^a/x-enriched MM cells was increased in patients with symptomatic disease and at relapse. These data suggest an important role of SLe^a/x and platelets in MM disease progression and resistance to therapy.

Flow cytometry is a highly sensitive and specific approach for discriminating between normal and clonal plasma cells in multiple myeloma. Uniform response criteria after treatment have been established by the International Myeloma Working Group and the EuroFlow Group; however, the way in which flow cytometry data are reported has suffered from no collaborative or multicentre efforts. This study, involving 8 expert laboratories and 12 clinical hematology units of the Lazio region in Italy, aims to produce a uniform and shared report among the various Centres. From the pre-analytical phase to sample processing, data acquisition, analysis, and evaluation of the potential limitations and pitfalls of the entire process, the study reaches a final conclusion shared by laboratories and clinicians according to the most updated principles and recommendations. The aim was to identify the necessary data to be included in the clinical report by using multiple-choice questionnaires at every single stage of the process. An agreement of more than 75% of the laboratories was considered mandatory for the data to be included in the report. By ensuring the operational autonomy of each laboratory, this study provides a clear report that limits subjective interpretations and highlights possible bias in the process, better supporting clinical decision-making.

The GIMEMA group investigated the efficacy, safety, and rates of discontinuations of the ibrutinib and rituximab regimen in previously untreated and unfit patients with chronic lymphocytic leukemia (CLL). Treatment consisted of ibrutinib, 420 mg daily, and until disease progression, and rituximab (375 mg/sqm, given weekly on week 1–4 of month 1 and day 1 of months 2–6). This study included 146 patients with a median age of 73 years, with IGHV unmutated in 56.9% and TP53 disrupted in 22.2%. The OR, CR, and 48-month PFS rates were 87%, 22.6%, and 77%, respectively. Responses with undetectable MRD were observed in 6.2% of all patients and 27% of CR patients. TP53 disruption (HR 2.47; p = 0.03) and B-symptoms (HR 2.91; p = 0.02) showed a significant and independent impact on PFS. The 48-month cumulative rates of treatment discontinuations due to disease progression (DP) or adverse events (AEs) were 5.6% and 29.1%, respectively. AEs leading more frequently to treatment discontinuation were atrial fibrillation in 8% of patients, infections in 8%, and non-skin cancers in 6%. Discontinuation rates due to AEs were higher in male patients (HR: 0.46; p = 0.05), patients aged ≥70 years (HR 5.43, p = 0.0017), and were managed at centers that enrolled p = 0.04). Patients who discontinued ibrutinib due to an AE showed a 24-month next treatment-free survival rate of 63%. In conclusion, ibrutinib and rituximab combination was an effective front-line treatment with sustained disease control in more than half of unfit patients with CLL. Careful monitoring is recommended to prevent and manage AEs in this patient population.

PNH is associated with abdominal vein thrombosis, which can cause splenomegaly and hypersplenism. The combination of thrombosis, splenomegaly, and thrombocytopenia (TST) is challenging because anticoagulants are indicated but thrombocytopenia may increase the bleeding risk. Splenectomy could alleviate thrombocytopenia and reduce portal pressure, but it can cause post-operative thromboses and opportunistic infections. We therefore sought to determine whether selective splenic artery embolization (SSAE) is a safe and effective alternative to splenectomy for TST in patients with PNH.