Disease characteristics and outcomes in younger adults with primary and secondary myelofibrosis.
Myelofibrosis (MF) is a rare haematopoietic disorder, commonly diagnosed in the 6th decade: less than 20% are diagnosed before the age of 50 years. In this retrospective study we included all patients given a diagnosis of World Health Organization-defined primary or secondary MF when aged ≤50 years. Forty-three patients with a median age of 43 years were included. Median follow up was 44 months. Twenty-two (51%) harboured the JAK2 V617F mutation, 18/43 (42%) CALR, 0/43 (0%) MPL mutations and 3/43 (7%) were 'Triple Negative' (TN). At the time of diagnosis, no significant differences existed in haematological and clinical phenotypes between JAK2, CALR and TN patients. The frequency of splenomegaly was greater (P = 0·047) in the JAK2-mutated group compared to CALR-mutated patients. In the whole cohort, the 5-year probability of developing anaemia, thrombocytopenia and marked leucocytosis was 24%, 10% and 13% respectively. Finally, the cumulative incidence of thrombotic events and progression to acute myeloid leukaemia was 1% and 0·5% patient-year respectively. No death was reported during the follow-up. These findings suggest that MF in younger patients may have a more indolent course when compared to older patients.
Department of Haematology, Guy's and St Thomas' NHS Foundation Trust, London, UK.|Department of Haematology, Geneva University Hospitals, Geneva, Switzerland.
Yan
Y
Beauverd
Department of Haematology, Guy's and St Thomas' NHS Foundation Trust, London, UK.
Samah
S
Alimam
Department of Haematology, Guy's and St Thomas' NHS Foundation Trust, London, UK.|Department of Haematological Medicine, King's College Hospital NHS Foundation Trust, London, UK.
Donal P
DP
McLornan
Department of Haematology, Guy's and St Thomas' NHS Foundation Trust, London, UK.
Deepti H
DH
Radia
Department of Haematology, Guy's and St Thomas' NHS Foundation Trust, London, UK. claire.harrison@gstt.nhs.uk.
Claire N
CN
Harrison
D059786:Abnormal Karyotype; D000328:Adult; D000740:Anemia / Q000175:diagnosis; D000970:Antineoplastic Agents / Q000627:therapeutic use; D015415:Biomarkers; D018450:Disease Progression; D005260:Female; D006801:Humans; D053614:Janus Kinase 2 / Q000235:genetics; D015470:Leukemia, Myeloid, Acute / Q000175:diagnosis / Q000209:etiology / Q000401:mortality; D007964:Leukocytosis / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D009154:Mutation; D063868:Patient Outcome Assessment; D010641:Phenotype; D055728:Primary Myelofibrosis / Q000175:diagnosis* / Q000209:etiology / Q000401:mortality* / Q000628:therapy; D011379:Prognosis; D047428:Protein Kinase Inhibitors / Q000627:therapeutic use; D013921:Thrombocytopenia / Q000175:diagnosis; D055815:Young Adult
D000970:Antineoplastic Agents; D015415:Biomarkers; D047428:Protein Kinase Inhibitors; D053614:Janus Kinase 2
CALR; JAK2; Myelofibrosis