Finke, Christy M.

DNMT3A mutations are seen in ∼5% of patients with chronic myelomonocytic leukemia (CMML) and thus far, have had an indeterminate prognostic impact on survival. We carried out this study to assess the prognostic impact of DNMT3A mutations on a larger informative cohort of CMML patients (n = 261). DNMT3A mutations were seen in 6% (n = 16); 56% (n = 9) male, with a median age of 64 years. Eighty‐one % of DNMT3A mutations were missense, with the Arg882 mutational hot spot accounting for 63% of all changes. Five (31%) patients had an abnormal karyotype whereas concurrent gene mutations (SF3B1/SRSF2/U2AF1−56%, TET2−50%, and ASXL1−25%) were seen in all patients. Apart from a higher frequency of SF3B1 (P = 0.0001) and PTPN11 (P = 0.005) mutations and a lower frequency of SRSF2 (P = 0.004) mutations, there were no significant differences between DNMT3A mutated patients and their wildtype counterparts. In univariate analysis, survival was shorter in DNMT3A mutated (median 8 months) versus wildtype (median 27 months) patients (P = 0.0007; HR 2.9, 95% CI 1.5–5.7); with other variables of significance including lower hemoglobin (P = 0.002), higher leukocyte count (P = 0.0009), higher monocyte count (P = 0.0012), circulating blast % (P = 0.001), circulating immature myeloid cells (P = 0.01), bone marrow blast % (P = 0.045), abnormal karyotype (P = 0.02), and ASXL1 (P = 0.01) mutations. In a multivariable model that included the aforementioned variables, when both DNMT3A and ASXL1 mutations were added, only DNMT3A (P < 0.0001) and ASXL1 (P = 0.004) mutations remained significant. DNMT3A mutations were also predictive of a shortened leukemia‐free survival. These findings warrant inclusion of DNMT3A mutations in molecularly integrated CMML prognostic models. Am. J. Hematol. 92:56–61, 2017. © 2016 Wiley Periodicals, Inc.

In routine practice, the World Health Organization classification of systemic mastocytosis (SM) is also the de facto prognostic system; a core value is distinguishing indolent (ISM) from advanced SM (includes aggressive SM [ASM], SM with associated hematological neoplasm [SM‐AHN] and mast cell leukemia [MCL]). We sequenced 27 genes in 150 SM patients to identify mutations that could be integrated into a clinical‐molecular prognostic model for survival. Forty four patients (29%) had ISM, 25 (17%) ASM, 80 (53%) SM‐AHN and 1 (0.7%) MCL; overall KITD816V prevalence was 75%. In 87 patients, 148 non‐KIT mutations were detected; the most frequently mutated genes were TET2 (29%), ASXL1 (17%), and CBL (11%), with significantly higher mutation frequency in SM‐AHN > ASM > ISM (P < 0.0001). In advanced SM, ASXL1 and RUNX1 mutations were associated with inferior survival. In multivariate analysis, age > 60 years (HR = 2.4), hemoglobin < 10 g/dL or transfusion‐dependence (HR = 1.7), platelet count < 150 × 109/L (HR = 3.2), serum albumin < 3.5 g/dL (HR = 2.6), and ASXL1 mutation (HR = 2.3) were associated with inferior survival. A mutation‐augmented prognostic scoring system (MAPSS) based on these parameters stratified advanced SM patients into high‐, intermediate‐, and low‐risk groups with median survival of 5, 21 and 86 months, respectively (P < 0.0001). These data should optimize risk‐stratification and treatment selection for advanced SM patients. Am. J. Hematol. 91:888–893, 2016. © 2016 Wiley Periodicals, Inc.

About 85% of patients with essential thrombocythemia (ET) harbor one of three driver mutations: JAK2, calreticulin (CALR), and MPL; the remaining ( ∼15%) are wild type for all three mutations and are referred to as being “triple negative.” Furthermore, CALR mutations in ET are structurally classified as type 1/type 1‐like or type 2/type 2‐like variants. The objective of the current study was to examine the impact of CALR mutation variant stratified driver mutational status on overall (OS), myelofibrosis‐free (MFFS), thrombosis‐free, and leukemia‐free survival (LFS) in ET; 495 patients (median age 58 years; 61% females) with ET were fully annotated for the their driver mutational status: 321 (65%) harbored JAK2, 109 (22%) CALR, and 12 (2%) MPL mutations and 11% were triple‐negative. Among the 109 CALR‐mutated cases, 52% were classified as type 1/type 1‐like and 48% as type 2/type 2‐like. In univariate analysis, triple‐negative patients displayed the best and MPL mutated the worst OS (P = 0.007); however, the difference in OS was no longer apparent on multivariable analysis that included age and sex as covariates (P = 0.5). LFS was also similar among the different mutational groups (P = 0.6) whereas MFFS was significantly shorter in MPL‐mutated patients on both univariate and multivariable analyses (age‐adjusted P = 0.02; HR 7.9, 95% CI 2.0–31.5). Also in multivariable analysis that included thrombosis history, age, and cardiovascular risk factors, the presence of JAK2 or MPL mutations was independently associated with higher risk of thrombosis (P = 0.02; HR 1.9, 95% CI 1.1–3.4). In conclusion, driver mutational status in ET does not appear to influence overall or LFS, even after CALR variant stratification. However, the presence of MPL mutations might be associated with a higher risk of fibrotic transformation and the presence of JAK2/MPL mutations with higher risk of thrombosis. Am. J. Hematol. 91:503–506, 2016. © 2016 Wiley Periodicals, Inc.

Refractory anemia with ring sideroblasts and thrombocytosis (RARS‐T) shares overlapping features of myelodysplastic syndromes (MDS) and myeloproliferative neoplasms (MPN). RARS‐T is characterized by SF3B1 and JAK2 mutations and prognosis is considered to be better than MDS but not as good as MPN. The objective of the study was to identify predictors of survival in RARS‐T. We analyzed clinical and laboratory variables in 82 patients and applied a 27‐gene NGS assay to 48 marrow samples obtained at diagnosis. 94% of patients had ≥1 mutations; common mutations being: SF3B1 85%, JAK2 V617F 33%, ASXL1 29%, DNMT3A 13%, SETBP1 13% and TET2 10%. In a multivariable survival analysis ( n = 82), anemia ( P = 0.02) [HB< 10 gm/dl: HR 2.3, 95% CI 1.2–4.6] and abnormal karyotype ( P =.01) [HR 6.1, 95% CI 2.7‐13.8] were independently prognostic for inferior survival. In patients with NGS information ( n = 48), univariate analysis showed association between poor survival and presence of SETBP1 ( P = 0.04) or ASXL1 ( P = 0.08) mutations whereas the absence of these mutations ( ASXL1 wt/ SETBP1 wt) was favorable ( P = 0.04); the number of concurrent mutations did not provide additional prognostication ( P = 0.3). We developed a HR‐weighted prognostic model, with 2 points for an abnormal karyotype, 1 point for either ASXL1 and/or SETBP1 mutations, and 1 point for a HB level < 10 gm/dl, which effectively stratified patients into three risk categories; low (0 points), intermediate (1 point) and high (≥2 points), with median survivals of 80, 42 and 11 months respectively ( P = 0.01). In summary, we confirm the unique mutational landscape in RARS‐T and provide a novel mutation‐enhanced prognostic model. Am. J. Hematol. 91:492–498, 2016. © 2016 Wiley Periodicals, Inc.

Colony stimulating factor 3 receptor gene (CSF3R) mutations have recently been associated with chronic neutrophilic leukemia (CNL). Fourteen patients with CSF3R‐mutated CNL (median age 67 years; 57% males) were screened for additional mutations; 8 (57%) and 5 (38%) harbored an ASXL1 and/or SETBP1 mutation (two patients expressed both), respectively. Two patients developed blastic transformation, both SETBP1‐mutated and ASXL1‐unmutated, whereas two other cases evolved into chronic myelomonocytic leukemia (CMML), both ASXL1‐mutated and SETBP1‐unmutated. Median survival was 23.2 months (10 deaths documented). On multivariable analysis mutated ASXL1 (P = 0.009; HR 19.6, 95% CI 2.1–184.1) and thrombocytopenia (P = 0.005; HR 28.8, 95% CI 2.8–298.2) were independently predictive of shortened survival. This study provides information on the natural history of CSF3R‐mutated CNL and identifies mutant ASXL1 and thrombocytopenia as risk factors for survival. The study also suggests pathogenetic roles for SETBP1 and ASXL1 mutations in disease evolution into blast phase disease and CMML, respectively. Am. J. Hematol. 90:653–656, 2015. © 2015 Wiley Periodicals, Inc.

SummaryAmong 826 patients with primary myelofibrosis (PMF) and analysable metaphases on cytogenetic studies, 352 (42·6%) had abnormal karyotype, of which 240 (68·2%) were sole aberrations and 48 (13·6%) were complex; the most frequent abnormalities were 20q− (23·3%), 13q− (18·2%), +8 (11·1%), +9 (9·9%), chromosome 1q+ (9·7%) and −7/7q− (7·1%). Phenotypic correlates included: abnormal karyotype with anaemia (P = 0·02), leucopenia (P < 0·01) and thrombocytopenia (P < 0·01); complex karyotype with younger age (P = 0·04) and thrombocytopenia (P < 0·01); leucopenia with 20q−, +8 and −7/7q− and thrombocytopenia with 20q− and −7/7q−. Cytopenias were less likely to occur with 13q−. 476 patients were annotated for JAK2/CALR/MPL mutations; abnormal karyotype frequencies were 43% in JAK2, 42% CALR, 33% MPL mutated and 34% triple‐negative cases (P = 0·3). A proportion of patients were also screened for ASXL1, EZH2, IDH1, IDH2, SRSF2, U2AF1 and SF3B1 mutations; in all instances, mutational frequencies were higher in patients with normal karyotype, reaching significance for ASXL1 (P = 0·02) and U2AF1 (P = 0·01). 13q− was associated with mutant CALR (P = 0·03), +9 with mutant JAK2 (P = 0·02) and 20q− with mutant SRSF2 (P = 0·02). The current PMF study provides detailed cytogenetic information and correlations with mutations and clinical phenotype.