Curtis A. Hanson

DIPSS Plus: A Refined Dynamic International Prognostic Scoring System for Primary Myelofibrosis That Incorporates Prognostic Information From Karyotype, Platelet Count, and Transfusion Status

PURPOSE The Dynamic International Prognostic Scoring System (DIPSS) for primary myelofibrosis (PMF) uses five risk factors to predict survival: age older than 65 years, hemoglobin lower than 10 g/dL, leukocytes higher than 25 × 10(9)/L, circulating blasts ≥ 1%, and constitutional symptoms. The main objective of this study was to refine DIPSS by incorporating prognostic information from karyotype, platelet count, and transfusion status. PATIENTS AND METHODS Mayo Clinic databases for PMF were used to identify patients with available bone marrow histologic and cytogenetic information. RESULTS Seven hundred ninety-three consecutive patients were selected and divided into two groups based on whether or not their referral occurred within (n = 428; training set) or after (n = 365; test set) 1 year of diagnosis. Multivariable analysis identified DIPSS, unfavorable karyotype, platelets lower than 100 × 10(9)/L, and transfusion need as independent predictors of inferior survival. Hazard ratio (HR)-weighted adverse points were assigned to these variables to develop a composite prognostic model using the training set. The model was subsequently validated in the test set, and its application to all 793 patients resulted in median survivals of 185, 78, 35, and 16 months for low, intermediate-1 (HR, 2.2; 95% CI, 1.4 to 3.6), intermediate-2 (HR, 4.9; 95% CI, 3.2 to 7.7), and high-risk groups (HR, 10.7; 95% CI, 6.8 to 16.9), respectively (P < .001). Leukemia-free survival was predicted by the presence of thrombocytopenia or unfavorable karyotype (10-year risk of 31% v 12%; HR, 3.3; 95% CI, 1.9 to 5.6). CONCLUSION DIPSS plus effectively combines prognostic information from DIPSS, karyotype, platelet count, and transfusion status to predict overall survival in PMF. In addition, unfavorable karyotype or thrombocytopenia predicts inferior leukemia-free survival.

TET2 mutations and their clinical correlates in polycythemia vera, essential thrombocythemia and myelofibrosis

High-throughput DNA sequence analysis was used to screen for TET2 mutations in bone marrow-derived DNA from 239 patients with BCR-ABL-negative myeloproliferative neoplasms (MPNs). Thirty-two mutations (19 frameshift, 10 nonsense, 3 missense; mostly involving exons 4 and 12) were identified for an overall mutational frequency of ∼13%. Specific diagnoses included polycythemia vera (PV; n=89), essential thrombocythemia (ET; n=57), primary myelofibrosis (PMF; n=60), post-PV MF (n=14), post-ET MF (n=7) and blast phase PV/ET/MF (n=12); the corresponding mutational frequencies were ∼16, 5, 17, 14, 14 and 17% (P=0.50). Mutant TET2 was detected in ∼17 and ∼7% of JAK2V617F-positive and -negative cases, respectively (P=0.04). However, this apparent clustering of the two mutations was accounted for by an independent association between mutant TET2 and advanced age; mutational frequency was ∼23% in patients ⩾60 years old versus ∼4% in younger patients (P<0.0001). The presence of mutant TET2 did not affect survival, leukemic transformation or thrombosis in either PV or PMF; a correlation with hemoglobin <10 g per 100 ml in PMF was noted (P=0.05). We conclude that TET2 mutations occur in both JAK2V617F-positive and -negative MPN, are more prevalent in older patients, display similar frequencies across MPN subcategories and disease stages, and hold limited prognostic relevance.

Proposed criteria for the diagnosis of post-polycythemia vera and post-essential thrombocythemia myelofibrosis: a consensus statement from the international working group for myelofibrosis research and treatment

Proposed criteria for the diagnosis of post-polycythemia vera and post-essential thrombocythemia myelofibrosis: a consensus statement from the international working group for myelofibrosis research and treatment

Survival and Disease Progression in Essential Thrombocythemia Are Significantly Influenced by Accurate Morphologic Diagnosis: An International Study

PURPOSE The WHO diagnostic criteria underscore the role of bone marrow (BM) morphology in distinguishing essential thrombocythemia (ET) from early/prefibrotic primary myelofibrosis (PMF). This study examined the clinical relevance of such a distinction. METHODS Representatives from seven international centers of excellence for myeloproliferative neoplasms convened to create a clinicopathologic database of patients previously diagnosed as having ET (N = 1,104). Study eligibility criteria included availability of treatment-naive BM specimens obtained within 1 year of diagnosis. All bone marrows subsequently underwent a central re-review. RESULTS Diagnosis was confirmed as ET in 891 patients (81%) and was revised to early/prefibrotic PMF in 180 (16%); 33 patients were not evaluable. In early/prefibrotic PMF compared with ET, the 10-year survival rates (76% and 89%, respectively) and 15-year survival rates (59% and 80%, respectively), leukemic transformation rates at 10 years (5.8% and 0.7%, respectively) and 15 years (11.7% and 2.1%, respectively), and rates of progression to overt myelofibrosis at 10 years (12.3% and 0.8%, respectively) and 15 years (16.9% and 9.3%) were significantly worse. The respective death, leukemia, and overt myelofibrosis incidence rates per 100 patient-years for early/prefibrotic PMF compared with ET were 2.7% and 1.3% (relative risk [RR], 2.1; P < .001), 0.6% and 0.1% (RR, 5.2; P = .001), and 1% and 0.5% (RR, 2.0; P = .04). Multivariable analysis confirmed these findings and also identified age older than 60 years (hazard ratio [HR], 6.7), leukocyte count greater than 11 × 10(9)/L (HR, 2.01), anemia (HR, 2.95), and thrombosis history (HR, 2.81) as additional risk factors for survival. Thrombosis and JAK2V617F incidence rates were similar between the two groups. Survival in ET was similar to the sex- and age-standardized European population. CONCLUSION This study validates the clinical relevance of strict adherence to WHO criteria in the diagnosis of ET and provides important information on survival, disease complication rates, and prognostic factors in strictly WHO-defined ET and early/prefibrotic PMF.

Chromosome anomalies detected by interphase fluorescence in situ hybridization: correlation with significant biological features of B-cell chronic lymphocytic leukaemia

Summary. Fluorescence in situ hybridization (FISH) was used to detect 6q–, 11q–, +12, 13q–, 17p– and translocations involving 14q32 in interphase nuclei from blood and/or bone marrow from 113 patients with B‐cell chronic lymphocytic leukaemia (B‐CLL). A total of 87 patients (77%) had a FISH anomaly: 13q– × 1 was most frequent (64%) followed by 13q– × 2 (28%), +12 (25%), 11q– (15%), 17p– (8%) and 6q– (0%). FISH results for blood and bone marrow cells in 38 patients were similar. Purified CD5+/CD19+ cells from blood were studied in eight patients and results indicate that in some patients not all B cells have FISH anomalies. We used a defined set of hierarchical FISH risk categories to compare FISH results by stable versus progressive disease, age, sex, Rai stage, CD38+ expression and IgVH mutational status. Significant differences in FISH risk distributions were associated with Rai stage, disease status and CD38+, but not by age, sex or IgVH mutational status. To look for baseline factors associated with high‐risk disease, multivariate analysis of age, sex, Rai stage, CD38+ and disease status versus FISH risk category was performed. Importantly, only CD38+ was significantly associated with high‐risk FISH categories (+12, 11q– and 17p–) after adjustment for the effects of other variables.

Detection of mutant TET2 in myeloid malignancies other than myeloproliferative neoplasms: CMML, MDS, MDS/MPN and AML

Detection of mutant TET2 in myeloid malignancies other than myeloproliferative neoplasms: CMML, MDS, MDS/MPN and AML

Prevalence and clinicopathologic correlates of JAK2 exon 12 mutations in JAK2V617F-negative polycythemia vera

After accounting for misdiagnosis and treatment effect, allele-specific (AS)-PCR detects the JAK2V617F mutation in >95% of polycythemia vera (PV) patients. Using database inquiry, we identified 6 of a total 220 cases with PV that were JAK2V617F-negative (prevalence=3%). Of these, five cases (∼80%) were found to harbor one of the two JAK2 exon 12 mutations (F537-K539delinsL or N542-E543del) in bone marrow (BM) and/or peripheral blood cells. Similar screening of six additional cases – three each with idiopathic erythrocytosis (IE) or otherwise unexplained erythrocytosis (UE) – did not reveal either JAK2V617F or JAK2 exon 12 mutations. We found JAK2 exon 12 mutations in PV cases to be readily detected by both DNA sequencing and AS-PCR, regardless of whether BM or peripheral blood cells were used as the source for DNA. Although erythroid hyperplasia was the predominant histologic feature on BM examination, megakaryocyte abnormalities and reticulin fibrosis were noted in most PV patients harboring exon 12 mutations. However, similar BM morphologic changes can also be seen in some JAK2V617F-positive PV cases; therefore, distinct genotype–phenotype association cannot be established.

Analysis of clonal B‐cell CD38 and immunoglobulin variable region sequence status in relation to clinical outcome for B‐chronic lymphocytic leukaemia

Recent reports suggest that the expression of germline (GL) Ig variable region heavy‐chain genes (VH) is a negative prognostic factor for B‐cell chronic lymphocytic leukaemia (B‐CLL) patients and that CLL B‐cell CD38 expression may be a surrogate marker of Ig VH gene status. Currently, however, the usefulness of this surrogate marker is controversial. Therefore, our goal was to study the ability of CD38 to act as a surrogate marker for Ig VH somatic mutation (SM), and to identify differences in overall survival (OS), progression‐free survival (PFS) and response in B‐CLL patients based on these two markers. We first assessed the relationship between CD38 expression and Ig VH status on 131 B‐CLL patients, including 66 patients enrolled in three North Central Cancer Treatment Group Trials. Although the mean percentages of CD38+ clonal B cells were significantly higher for patients classified as GL versus SM, CD38 was not a reliable marker for clonal B‐cell SM. Overall, GL patients exhibited significantly shorter OS and PFS times than SM patients. Despite the inability of clonal B‐cell CD38 expression to predict Ig VH mutation status, patients with ≥ 30% CD38+ cells did have shorter PFS and OS times than did CLL patients with < 30% CD38+ cells. Thus, the relationship between CD38 expression and Ig VH mutation status in B‐CLL is not straightforward. Nevertheless, analysis in a co‐operative group clinical trial setting suggests that both B‐cell markers alone or in combination may have clinical usefulness. These data strongly encourage the study of these biological markers as they relate to disease heterogeneity in B‐CLL.

Low JAK2V617F allele burden in primary myelofibrosis, compared to either a higher allele burden or unmutated status, is associated with inferior overall and leukemia-free survival

The clinical relevance of JAK2V617F allele burden in primary myelofibrosis (PMF) has not been previously studied. Bone marrow-derived DNA from 199 patients with PMF was subjected to qualitative (n=199) and quantitative (n=129) analysis for V617F. Mutational frequency was 58% and median mutant allele burden ratio in V617F-positive patients was 29% (range, 1–74%). Multivariable analysis identified older age, platelet count ⩾100 × 109 l−1 and peripheral blood blast percentage <3% as being associated with a positive mutational status. The mere presence of the mutation did not affect the incidence of thrombosis (P=0.78), overall survival (P=0.22) or leukemia-free survival (P=0.5). The 129 patients with allele burden information were divided into four groups: V617F-negative (n=53) and V617F-positive with mutant allele burden in the lower quartile (n=19), middle quartiles (n=38) or upper quartile (n=19) range. Kaplan–Meier plots revealed significantly shortened overall (P=0.0008) and leukemia-free (P=0.01) survival for the lower quartile, but not for upper quartile allele burden group; independent prognostic relevance was validated by multivariable analysis. We conclude that low V617F allele burden in PMF might indicate the presence of an overriding V617F-negative clone that confers a more aggressive disease phenotype.

Long-term survival and blast transformation in molecularly annotated essential thrombocythemia, polycythemia vera, and myelofibrosis

Janus kinase 2 (JAK2) mutations define polycythemia vera (PV). Calreticulin (CALR) and myeloproliferative leukemia virus oncogene (MPL) mutations are specific to JAK2-unmutated essential thrombocythemia (ET) and primary myelofibrosis (PMF). We examined the effect of these mutations on long-term disease outcome. One thousand five hundred eighty-one patients from the Mayo Clinic (n = 826) and Italy (n = 755) were studied. Fifty-eight percent of Mayo patients were followed until death; median survivals were 19.8 years in ET (n = 292), 13.5 PV (n = 267; hazard ratio [HR], 1.8; 95% confidence interval [CI], 1.4-2.2), and 5.9 PMF (n = 267; HR, 4.5; 95% CI, 3.5-5.7). The survival advantage of ET over PV was not affected by JAK2/CALR/MPL mutational status. Survival in ET was inferior to the age- and sex-matched US population (P < .001). In PMF (n = 428), but not in ET (n = 576), survival and blast transformation (BT) were significantly affected by mutational status; outcome was best in CALR-mutated and worst in triple-negative patients: median survival, 16 vs 2.3 years (HR, 5.1; 95% CI, 3.2-8.0) and BT, 6.5% vs 25% (HR, 7.6; 95% CI, 2.8-20.2), respectively. We conclude that life expectancy in morphologically defined ET is significantly reduced but remains superior to that of PV, regardless of mutational status. In PMF, JAK2/CALR/MPL mutational status is prognostically informative.