Ketterling, Rhett P.

AbstractTrisomies of odd numbered chromosomes are seen in nearly half of patients with multiple myeloma (MM) and typically correlate with a hyperdiploid state and better overall survival (OS). We compared DNA ploidy of monoclonal plasma cells (as a surrogate for the presence of trisomies) assessed simultaneously by PCPRO (plasma cell proliferative index), a novel method that estimates DNA index by multi‐parametric flow cytometry to fluorescence in situ hybridization (FISH) in 1703 patients with plasma cell disorders. The distribution of ploidy was hyperdiploid: 759 (45%), diploid 765 (45%), hypodiploid: 71 (4%), tetraploid/near‐tetraploid: 108 (6%). FISH identified trisomies in 82% (621/756) of patients with hyperdiploidy by PCPRO and no trisomy by FISH was observed in 88% (730/834) of patients without hyperdiploidy. 95% (795/834) of patients without hyperdiploidy on PCPRO had one or less trisomy by FISH. Sensitivity and specificity of PCPRO for detecting hyperdiploidy was 86% (621/725) and 84% (730/865), respectively. Sensitivity increased to 94% (579/618) for patients with more than one trisomy. Newly diagnosed MM patients with hyperdiploidy on PCPRO (147/275) had better OS compared to nonhyperdiploid patients (median not reached vs 59 months, P = 0.008) and better progression free survival (median: 33 vs 23 months, P = 0.03). Within the hyperdiploidy group, patients with high‐hyperdiploidy (DNA index: 1.19‐1.50) versus those with low‐hyperdiploidy (DNA index: 1.05‐1.18) had superior OS (3 year OS of 88% vs 68% P = 0.03). Ploidy assessment by flow cytometry can provide rapid, valuable prognostic information and also reduces the number of copy number FISH probes required and hence the cost of FISH.

Abstract JAK2 mutations in myeloproliferative neoplasms (MPNs) are associated with the germline GGCC (46/1) haplotype. In 2010, we reported an association between shortened survival in primary myelofibrosis (PMF) and nullizygosity for the JAK2 46/1 haplotype. In the current study, we have increased the number of informative cases from 130 to 414 (median age 63 years; 63% males), in order to revisit with the phenotypic and prognostic relevance of the JAK2 46/1 haplotype in PMF. JAK2 46/1 haplotype was documented in 69% of the study patients, including 25% in homozygous and 44% in heterozygous state. Driver mutation frequency in patients homozygous/heterozygous/nullizygous for the 46/1 haplotype was 78%/60%/56% JAK2, 10%/20%/18% type 1‐like CALR, 3%/2%/5% type 2‐like CALR, 4%/8%/7% MPL, and 6%/10%/14% triple‐negative (P = .02). In univariate analysis, nullizygosity for the JAK2 46/1 haplotype was associated with inferior overall survival (HR 1.5, 95% CI 1.1‐1.9), most pronounced in JAK2 (P <.001), as opposed to CALR/MPL mutated (P = .48) or triple‐negative cases (P = .27). Multivariable analysis that included karyotype, driver mutational status and high‐molecular risk mutations confirmed the independent prognostic contribution of nullizygosity for the 46/1 haplotype (P = .02; HR 1.4, 95% CI 1.1‐1.8). Nullizygosity for 46/1 also remained significant in the context of the genetically‐inspired GIPSS risk model (P = .04), but not in the context of the integrated genetics‐clinical MIPSS70+ version 2.0 model (P = .4). Leukemia‐free survival was not affected by the 46/1 haplotype (P = .6). The current study confirms the association of nullizygosity for the JAK2 GGCC (46/1) haplotype with inferior survival in JAK2‐mutated PMF.

AbstractIn the last decade, several prognostic models for primary myelofibrosis (PMF) have been introduced and shown to be effective in predicting overall survival. The main objective for this study was to identify clinical and genetic markers of very long (20+ years) survival in PMF. A total of 1282 patients with PMF were considered (median age 65 years, range 19‐92; 63% males); 26 (2%) patients (median age 51 years, range 28‐71; 38% males) survived their disease for at least 20 years (long‐lived patients) and 626 (49%) patients (median age 68 years, range 27‐92; 66% males) died within 5 years of their diagnosis (short‐lived patients). Multivariable logistic regression analysis identified 7 variables that were associated with survival beyond 20 years: age ≤ 70 years (P = .002); female sex (P = .03); hemoglobin level ≥ 10 g/dL for women and ≥ 11 g/dL for men (P = .03), leukocyte count ≤25 × 109/L (P = .009), platelet count ≥100 × 109/L (P = .002), circulating blasts <2% (P = .03) and absence of constitutional symptoms (P = .04). Five‐year mortality was independently predicted by high‐molecular risk mutations (P < .001); unfavorable or very high risk karyotype (P < .001); absence of type 1/like CALR mutation (P < .001); age > 70 years (P < .001); constitutional symptoms (P < .001); hemoglobin level < 10 g/dL for women and < 11 g/dL for men (P < .001); leukocyte count >25 × 109/L (P = .004); and circulating blasts ≥2% (P = .001). This study suggests that genetic risk factors in PMF are associated with early mortality while survival beyond 20 years could be predicted by easily accessible clinical variables, including age, sex, blood counts, and symptoms.

Abstract Systemic mastocytosis (SM) is a clinically heterogeneous disease with prognosis chiefly assigned based on World Health Organization (WHO) morphologic subclassification. We assessed the feasibility of developing contemporary risk models for SM based on clinical and integrated clinical-genetics information. Diagnosis of SM was per WHO criteria, and karyotype and next-generation sequencing data were available in a subset of the total 580 patients (median age, 55 years; range, 18-88 years) seen at the Mayo Clinic between 1968 and 2015. Morphologic subcategories were indolent/smoldering in 291 (50%) and “advanced” in 289 (50%): SM with an associated hematological neoplasm in 199, aggressive SM in 85, and mast cell leukemia in 5. Multivariable analysis of clinical variables identified age &gt;60 years, advanced SM, thrombocytopenia &lt;150 × 109/L, anemia below sex-adjusted normal, and increased alkaline phosphatase (ALP) as independent risk factors for survival; respective hazard ratios (HRs) 95% confidence intervals (95% CIs) were 2.5 (1.9-3.4), 2.7 (1.8-4.0), 2.5 (1.9-3.4), 2.2 (1.6-3.1), and 2.1 (1.5-3.0). In addition, ASXL1 (HR, 4.5; 95% CI, 2.6-7.6), RUNX1 (HR, 4.3; 95% CI, 1.3-10.8), and NRAS (HR, 5.0, 95% CI, 1.5-13.2) mutations were independently associated with inferior survival. Combined clinical, cytogenetic, and molecular risk factor analysis confirmed the independent prognostic contribution of adverse mutations (2.6, 1.6-4.4), advanced SM (4.0, 1.8-10.0), thrombocytopenia (2.8, 1.7-4.5), increased ALP (2.1, 1.2-4.0), and age &gt;60 years (2.2, 1.3-3.6). These data were subsequently used to develop clinical and hybrid clinical-molecular risk models. The current study advances 2 complementary risk models for SM and highlights the independent prognostic contribution of mutations.

To improve the outcome of relapsed/refractory acute myeloid leukemia (AML), a randomized phase II trial of three novel regimens was conducted. Ninety patients were enrolled and were in first relapse or were refractory to induction/re‐induction chemotherapy. They were randomized to the following regimens: carboplatin‐topotecan (CT), each by continuous infusion for 5 days; alvocidib (formerly flavopiridol), cytarabine, and mitoxantrone (FLAM) in a timed sequential regimen; or sirolimus combined with mitoxantrone, etoposide, and cytarabine (S‐MEC). The primary objective was attainment of a complete remission (CR). A Simon two‐stage design was used for each of the three arms. The median age of the patients in the FLAM arm was older at 62 years compared with 55 years for the CT arm and the S‐MEC arm. The overall response was 14% in the CT arm (5/35, 90% CI 7%‐35%), 28% in the FLAM arm (10/36, 90% CI, 16%‐43%), and 16% in the S‐MEC arm (3/19, 90% CI, 4%‐36%). There were nine treatment‐related deaths, seven of which occurred in the FLAM arm with four of these in elderly patients. We conclude that the FLAM regimen had an encouraging response rate and should be considered for further clinical development but should be used with caution in elderly patients.

AbstractObjectiveAcute myeloid leukemia (AML) can be subtyped based on recurrent cytogenetic and molecular genetic abnormalities with diagnostic and prognostic significance. Although cytogenetic characterization classically involves conventional chromosome and/or fluorescence in situ hybridization (FISH) assays, limitations of these techniques include poor resolution and the inability to precisely identify breakpoints.MethodWe evaluated whether an NGS‐based methodology that detects structural abnormalities and copy number changes using mate pair sequencing (MPseq) can enhance the diagnostic yield for patients with AML.ResultsUsing 68 known abnormal and 20 karyotypically normal AML samples, each recurrent primary AML‐specific abnormality previously identified in the abnormal samples was confirmed using MPseq. Importantly, in eight cases with abnormalities that could not be resolved by conventional cytogenetic studies, MPseq was utilized to molecularly define eight recurrent AML‐fusion events. In addition, MPseq uncovered two cryptic abnormalities that were missed by conventional cytogenetic studies. Thus, MPseq improved the diagnostic yield in the detection of AML‐specific structural rearrangements in 10/88 (11%) of cases analyzed.ConclusionUtilization of MPseq represents a precise, molecular‐based technique that can be used as an alternative to conventional cytogenetic studies for newly diagnosed AML patients with the potential to revolutionize the diagnosis of hematologic malignancies.