Patients With Early Myelofibrosis Need Improved Prognostic Models, Study Says

The findings, say the researchers, highlight a need for prognostic models specific to patients with prefibrotic primary myelofibrosis (pre-PMF).

A study abstract presented at the European Hematology Association 2021 Virtual Congress is calling attention to a need for prognostic models specifically for patients with prefibrotic primary myelofibrosis (pre-PMF).1

The study data revealed that while the International Prognostic Scoring System (IPSS), the Dynamic IPSS (DIPSS), and DIPSS-plus were individually associated with survival in patients with overt-PMF, they were not for patients with pre-PMF.

In multivariate analysis, all 3 models were predictors of both progression-free survival (PFS) and overall survival (OS). However, following a subanalysis that accounted for histological stage, the models remained predictors of both survival measures in patients with overt-PMF but not the 47.8% of patients with pre-PMF.

“These findings identify a flaw in prognostic stratification applying the available scoring systems and alarms for the need of validated scores specifically for pre-PMF [patients],” explain the authors of the study abstract.

Pre-PMF was first recognized by the World Health Organization (WHO) in 2016 when the organization included distinct criteria for pre-PMF and overt-PMF, with criteria mainly relating to bone marrow morphology and fibrosis grade.2

Prior to the 2016 criteria, the 2008 WHO classification did not define the grade of fibrosis.

“In the recent years, prognostic models have been validated for primary myelofibrosis, initially based exclusively on clinical variables, namely the International Prognostic Scoring System and the Dynamic IPSS,” explained the authors. “Cytogenetics was incorporated in the most recent scores such as the DIPSS-plus. However, the applicability of PMF scoring systems in the recently recognized prefibrotic PMF has not been validated.”

The study collected data from 90 patients who received a PMF diagnosis between 2010 and 2019, with prognostic scores calculated based on the clinical and laboratory information collected at diagnosis. The patients were a median age of 68 years.

Across the patients, the overall PFS was 101.7 months and the overall OS was 124.6 months. Outside of the prognostic models, histological stage, increased lactate dehydrogenase, and splenomegaly were associated with both PFS and OS.

References

1. Gomes R, Duarte S, Afonso C, et al. IPSS, DIPSS and DIPSS-plus: predictive value for survival in primary myelofibrosis stages. Presented at: EHA2021 Virtual; June 9-17, 2021. Abstract EP1114.

2. Guglielmelli P, Pacilli A, Rotunno G, et al. Presentation and outcome of patients with 2016 WHO diagnosis of prefibrotic and overt primary myelofibrosis. Blood. 2017;129(24):3227-3236. doi:10.1182/blood-2017-01-761999