A study examined relapse in patients with myelofibrosis and blast-phase myeloproliferative neoplasms after allogeneic stem cell transplant. Among 47 patients treated between 2013 and 2024, 21% experienced recurrence, with 3- and 5-year relapse rates both at 35%. Molecular relapse typically appeared about six months after transplant and was often detected by declining donor chimerism.
Donor lymphocyte infusion (DLI) was used to treat early relapse, with over half of patients achieving molecular remission. Responses were better in patients with CALR type 1-like or MPL mutations, while those with JAK2 mutations had mixed results. More advanced hematologic relapse occurred in a smaller group and was linked to poor outcomes, especially in aggressive disease.
The findings highlight relapse as a major challenge but suggest early intervention with DLI and emerging targeted therapies may improve outcomes.