Clinical Features, Gene Alterations, and Outcomes in Prefibrotic and Overt Primary and Secondary Myelofibrotic Patients

A comparative retrospective study of pre-fibrotic primary myelofibrosis versus overtly fibrotic stage in Qatar: clinicopathological, genetic landscape, risk stratification and survival data (2008-2021) - a single center experience

BACKGROUND

In MENA region, there is a lack of evidence on Primary Myelofibrosis (PMF), leading to its underrepresentation in medical literature. This study marks the first comprehensive report on PMF data in Qatar, presenting findings from a single-center study spanning 13 years (2008-2021).

METHODS

Clinicopathological data, genetic features, and disease progression parameters of pre-PMF and overt PMF subgroups were collected. Overall survival (OS), progression-free survival (PFS), DIPSS plus four categories and merged low and high-risk DIPSS scoring groups were assessed.

RESULTS

Pre-PMF patients showed higher hemoglobin (P < 0.001), and platelet counts (P < 0.05) but lower blast counts, LDH levels, constitutional symptoms (P < 0.0001), and splenomegaly (P < 0.010) than overt PMF patients. JAK2 V617F mutation was more common in pre-PMF (P = 0.059), while unfavorable karyotypes were exclusive to overt PMF (P = 0.028). Median overall survival was significantly longer at 276.9 months (IQR: 315.9, 276.9 months) to what was previously reported. Overt PMF patients predominantly fell into the higher DIPSS risk category (P < 0.001) and showed greater disease progression than pre-PMF (P < 0.0001). Complications including refractory anaemia (P < 0.001) and leukemic transformation (P = 0.043), increased notably in the high-risk group. Furthermore, 86.2% of high-risk patients required treatment versus 59.4% of the lower-risk group (P = 0.020).

CONCLUSIONS

To the best of our knowledge our research represents the first and largest published dataset on PMF in MENA region to be published. Merged DIPSS plus scoring came to be a pragmatic tool for defining high-risk patients who significantly differ in mortality, progression, need for treatment and leukemic transformation.

Genetic and immunologic features associated with thrombocytopenia progression and poor prognosis in patients with myelofibrosis

Introduction

Myelofibrosis, which includes primary myelofibrosis (PMF) and secondary myelofibrosis (SMF), can exhibit cytopenic features associated with poor outcomes; however, the underlying mechanisms are unclear. Moreover, characterized by its aggressive nature and limited therapeutic options, myelofibrosis poses a major clinical challenge in hematology. Therefore, in this study, we aimed to identify genetic and immunologic features associated with thrombocytopenia progression and poor prognosis.

Methods

The study involved 226 patients with PMF or SMF, who were categorized into three groups: platelet count ≥ 100 × 109/L (PLT ≥ 100 group; n = 131), progression to thrombocytopenia (PROG group; n = 64), and platelet count < 100 × 109/L (PLT < 100 group; n = 31).

Results

Survival analysis revealed 4-year overall survival rate of 57.7%, 89.4%, and 93.9% for the PLT < 100, PROG, and PLT ≥ 100 groups, respectively. Time-dependent covariate analysis of the PLT ≥ 100 and PROG groups revealed inferior overall survival rate of the PROG group. Multivariate analysis indicated that progression to thrombocytopenia and ASXL1 and IDH1 mutations were associated with poor overall survival. Flow cytometry revealed fewer CD45RA+CD4+ T cells in the PROG group than in the PLT ≥ 100 group. ASXL1 mutations were more prevalent in the PROG group than in the other groups, correlating with a reduced number of CD45RA+CD4+ T cells.

Discussion

ASXL1 mutation and low CD45RA+CD4+ T-cell counts correlated with progression to thrombocytopenia. Our findings underscore the clinical significance of thrombocytopenia dynamics in MF progression and prognosis, with implications for patient management and therapeutic interventions.

SOHO State of the Art Updates and Next Questions | Diagnosis, Outcomes, and Management of Prefibrotic Myelofibrosis

Prefibrotic primary myelofibrosis (prefibrotic PMF) is a myeloproliferative neoplasm with distinct characteristics comprising histopathological and clinico-biological parameters. It is classified as a subtype of primary myelofibrosis. In clinical practice, it is essential to correctly distinguish prefibrotic PMF from essential thrombocythemia especially but also overt PMF besides other myeloid neoplasms. Risk stratification and survival outcomes for prefibrotic PMF are worse than that of ET but better than that of overt PMF. Rates of progression to overt PMF and blast phase disease are also higher for prefibrotic PMF than ET. In this review we first discuss the historical context to the evolution of prefibrotic PMF as an entity, its presenting features and diagnostic criteria. We emphasize the differences between prefibrotic PMF, ET, and overt PMF with regards to presenting features and disease outcomes including thrombohemorrhagic events and progression to fibrotic and blast phase disease. Next, we discuss the risk stratification models and contextualize these in the setting of clinical management. We share our view of personalizing treatment to address unique patient needs in the context of currently available management options. Lastly, we discuss areas of critical need in clinical research and speculate on the possibility of future disease course modifying therapies in prefibrotic PMF.

Conventional Cytogenetic Analysis and Array CGH + SNP Identify Essential Thrombocythemia and Prefibrotic Primary Myelofibrosis Patients Who Are at Risk for Disease Progression

The Philadelphia chromosome-negative myeloproliferative neoplasms (Ph-MPNs) are a heterogeneous group of clonal hematopoietic malignancies that include polycythemia vera (PV), essential thrombocythemia (ET), and the prefibrotic form of primary myelofibrosis (prePMF). In this study, we retrospectively reviewed the karyotypes from conventional cytogenetics (CC) and array Comparative Genomic Hybridization + Single Nucleotide Polymorphism (aCGH + SNP) in patients with ET or prePMF to determine whether the combined analysis of both methodologies can identify patients who may be at a higher risk of disease progression. We performed a comprehensive genomic review on 169 patients with a clinical diagnosis of ET (154 patients) or prePMF (15 patients). Genomic alterations detected by CC or array-CGH + SNP were detected in 36% of patients. In patients who progressed, 68% had an abnormal genomic finding by either technology. There was a shorter progression-free survival (PFS) among patients who were cytogenetically abnormal or who were cytogenetically normal but had an abnormal aCGH + SNP result. Leveraging the ability to detect submicroscopic copy number alterations and regions of copy neutral-loss of heterozygosity, we identified a higher number of patients harboring genomic abnormalities than previously reported. These results underscore the importance of genomic analysis in prognostication and provide valuable information for clinical management and treatment decisions.