# Results from a US modified Delphi consensus to define disease progression and disease modification in polycythemia Vera

## TL;DR

Experts used a modified Delphi method to define disease progression and modification in polycythemia vera, aiming to improve treatment strategies.

## Contribution

A consensus-based framework for defining disease progression and modification in polycythemia vera was developed.

## Key findings

- 39 out of 41 statements achieved consensus among specialists.
- Statements on response assessment and treatment selection had the highest agreement.
- The consensus aims to support better therapeutic strategies for polycythemia vera.

## Abstract

Within 15 years of diagnosis, around 15% of polycythemia vera (PV) cases progress to post-PV myelofibrosis, and around 3% transform to acute myeloid leukemia within 10 years. Risk factors for disease progression include advanced age and the presence of certain acquired myeloid-relevant mutations. A better understanding of what defines disease progression in PV is essential when evaluating treatment options that enable disease modification and improved patient outcomes. A modified-Delphi method was used to convene a virtual steering group (SG) of seven US-based clinical physicians specializing in the management and treatment of PV. The group generated 41 consensus statements across six main domains. A survey was developed from these statements and shared with a broader panel of specialists, using a four-point Likert scale. The results were analyzed to determine the level of agreement for each statement. The consensus threshold was set at 75% agreement. A total of 61 responses were received from hematologist-oncologists (n = 56), oncologists (n = 3), and hematologists (n = 2). On analysis, 39/41 (95%) statements achieved consensus agreement, and 2/41 (5%) failed to achieve consensus. Consensus statements related to response assessment adjudication, treatment selection, and disease progression scored the highest, with 92% consensus among the wider panel. Based on the consensus, the SG agreed on a set of recommendations for defining disease progression and disease modification in PV. These recommendations aim to improve understanding of the disease course to support the development of more effective therapeutic strategies.

The online version contains supplementary material available at 10.1007/s00277-025-06641-2.