Allogeneic Stem Cell Transplantation In Philadelphia Negative Myeloproliferative Or Myelodysplastic/Myeloproliferative Neoplasms: A Retrospective Analysis From The Societe Française De Greffe De Moelle Et De Therapie Cellulaire (SFGM-TC)

Philadelphia negative myeloproliferative or myeloproliferative/myelodysplastic neoplasms may evolve towards secondary acute myeloid leukemia (AML). The prognosis of such secondary leukemia is very poor. At present, there are only a few reports assessing the outcome of adult patients with a philadelphia negative myeloproliferative or myeloproliferative/myelodysplastic neoplasm in blast phase (MPN-BP) who received allogeneic stem cell transplantation (allo-SCT).

in this retrospective study, inclusion criteria were: (i) adult patients with a MPN-BP (ii) who received first allo-SCT (iii) between 2000 and 2010 (iv) irrespective of the stem cell source or conditioning regimen. MPN with <20% blasts in blood/bone marrow and AML secondary to myelodysplastic syndromes were excluded from this analysis.

60 patients were included. MPN, AML and allo-SCT characteristics are described in table 1. Median age at allo-SCT was 57 (range, 30-68). Patients received allo-SCT in first complete remission (CR1), CR2 or in advanced disease in 22 (37%), 4 (7%) and 34(57%) of cases, respectively. Engraftment was achieved in 55 cases (92%). With a median follow-up of 31 months (range, 25-44), the 3-year overall survival (OS) and Leukemia-Free-Survival (LFS) were respectively 18% and 9%. The 3-year transplant-related mortality (TRM) was 24% whereas relapse incidence was 68%. The 3-year LFS of patients grafted in CR (n=26) was 18% whereas the 3-year LFS of patients allografted in advanced disease (n=34) was only 3% (p=0.008). In the CR group, the 3-year TRM was 24% whereas relapse incidence was 61%. Intermediate or good AML karyotype (3-year LFS of 33% versus 10% for adverse AML karyotype, p=0.03) and the absence of a previous thrombotic event (3-year LFS of 24% versus 0, p=0.02) were associated with an improved LFS in patients allografted in CR.

These results suggest that the outcome of patients with a MPN-BP is dismal despite allo-SCT due to a high relapse incidence even in patients transplanted in CR. Outside a clinical trial, allo-SCT should be mainly proposed to patients in CR. New strategies are mandatory to improve the outcome of patients in blast phase.

No relevant conflicts of interest to declare.