Spectrum of clonal hematopoiesis in VEXAS syndrome.

Vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic (VEXAS) syndrome is caused by somatic mutations in UBA1 (UBA1mut) and characterized by heterogenous systemic autoinflammation and progressive hematologic manifestations, meeting criteria for myelodysplastic syndrome (MDS) and plasma cell dyscrasias. The landscape of myeloid-related gene mutations leading to typical clonal hematopoiesis (CH) in these patients is unknown. Retrospectively, we screened 80 patients with VEXAS for CH in their peripheral blood (PB) and correlated the findings with clinical outcomes in 77 of them. UBA1mut were most common at hot spot p.M41 (median variant allele frequency [VAF] = 75%). Typical CH mutations cooccurred with UBA1mut in 60% of patients, mostly in DNMT3A and TET2, and were not associated with inflammatory or hematologic manifestations. In prospective single-cell proteogenomic sequencing (scDNA), UBA1mut was the dominant clone, present mostly in branched clonal trajectories. Based on integrated bulk and scDNA analyses, clonality in VEXAS followed 2 major patterns: with either typical CH preceding UBA1mut selection in a clone (pattern 1) or occurring as an UBA1mut subclone or in independent clones (pattern 2). VAF in the PB differed markedly between DNMT3A and TET2 clones (median VAF of 25% vs 1%). DNMT3A and TET2 clones associated with hierarchies representing patterns 1 and 2, respectively. Overall survival for all patients was 60% at 10 years. Transfusion-dependent anemia, moderate thrombocytopenia, and typical CH mutations, each correlated with poor outcome. In VEXAS, UBA1mut cells are the primary cause of systemic inflammation and marrow failure, being a new molecularly defined somatic entity associated with MDS. VEXAS-associated MDS is distinct from classical MDS in its presentation and clinical course.

Asxl1 loss cooperates with oncogenic Nras in mice to reprogram the immune microenvironment and drive leukemic transformation.

Mutations in chromatin regulator ASXL1 are frequently identified in myeloid malignancies, in particular ∼40% of patients with chronic myelomonocytic leukemia (CMML). ASXL1 mutations are associated with poor prognosis in CMML and significantly co-occur with NRAS mutations. Here, we show that concurrent ASXL1 and NRAS mutations defined a population of CMML patients who had shorter leukemia-free survival than those with ASXL1 mutation only. Corroborating this human data, Asxl1-/- accelerated CMML progression and promoted CMML transformation to acute myeloid leukemia (AML) in NrasG12D/+ mice. NrasG12D/+;Asxl1-/- (NA) leukemia cells displayed hyperactivation of MEK/ERK signaling, increased global levels of H3K27ac, upregulation of Flt3. Moreover, we find that NA-AML cells overexpressed all the major inhibitory immune checkpoint ligands: programmed death-ligand 1 (PD-L1)/PD-L2, CD155, and CD80/CD86. Among them, overexpression of PD-L1 and CD86 correlated with upregulation of AP-1 transcription factors (TFs) in NA-AML cells. An AP-1 inhibitor or short hairpin RNAs against AP-1 TF Jun decreased PD-L1 and CD86 expression in NA-AML cells. Once NA-AML cells were transplanted into syngeneic recipients, NA-derived T cells were not detectable. Host-derived wild-type T cells overexpressed programmed cell death protein 1 (PD-1) and T-cell immunoreceptor with immunoglobulin and ITIM domains (TIGIT) receptors, leading to a predominant exhausted T-cell phenotype. Combined inhibition of MEK and BET resulted in downregulation of Flt3 and AP-1 expression, partial restoration of the immune microenvironment, enhancement of CD8 T-cell cytotoxicity, and prolonged survival in NA-AML mice. Our study suggests that combined targeted therapy and immunotherapy may be beneficial for treating secondary AML with concurrent ASXL1 and NRAS mutations.

Prognostic relevance of clonal hematopoiesis in myeloid neoplastic transformation in patients with follicular lymphoma treated with radioimmunotherapy.

While novel radioisotope therapies continue to advance cancer care, reports of therapy-related myeloid neoplasms (t-MN) have generated concern. The prevalence and role of clonal hematopoiesis (CH) in this process remain to be defined. We hypothesized that: (i) CH is prevalent in relapsed follicular lymphoma and is associated with t-MN transformation, and (ii) radiation in the form of radioimmunotherapy (RIT) plays a role in clonal progression. In this retrospective cohort study, we evaluated the prevalence and prognostic impact of CH on clinical outcomes in 58 heavily pre-treated follicular lymphoma patients who received RIT. Patients had been given a median of four lines of therapy before RIT. The prevalence of CH prior to RIT was 46%, while it was 67% (P=0.15) during the course of RIT and subsequent therapies in the paired samples. Fourteen (24%) patients developed t-MN. Patients with t-MN had a higher variant allele fraction (38% vs. 15%; P=0.02) and clonal complexity (P=0.03) than those without. The spectrum of CH differed from that in age-related CH, with a high prevalence of DNA damage repair and response pathway mutations, absence of spliceosome mutations, and a paucity of signaling mutations. While there were no clear clinical associations between RIT and t-MN, or overall survival, patients with t-MN had a higher mutant clonal burden, along with extensive chromosomal abnormalities (median survival, afer t-MN diagnosis, 0.9 months). The baseline prevalence of CH was high, with an increase in prevalence on exposure to RIT and subsequent therapies. The high rates of t-MN with marked clonal complexities and extensive chromosomal damage underscore the importance of better identifying and studying genotoxic stressors accentuated by therapeutic modalities.

ASXL1/TET2 genotype-based risk stratification outperforms ASXL1 mutational impact and is independent of mutant variant allele fractions in chronic myelomonocytic leukemia.

Not available.

Clonal Hematopoiesis of Indeterminate Potential Is Associated With Coronary Microvascular Dysfunction In Early Nonobstructive Coronary Artery Disease.

BACKGROUND: Clonal hematopoiesis (CH) of indeterminate potential (CHIP) is a risk factor for cardiovascular disease. The relationship between CHIP and coronary microvascular dysfunction (CMD) is unknown. The current study examines the association between CHIP and CH with CMD and the potential relationships in risk for adverse cardiovascular outcomes. METHODS: In this retrospective observational study, targeted next-generation sequencing was performed for 177 participants with no coronary artery disease who presented with chest pain and underwent routine coronary functional angiogram. Patients with somatic mutations in leukemia-associated driver genes in hematopoietic stem and progenitor cells were examined; CHIP was considered at a variant allele fraction ≥2%; CH was considered at a variant allele fraction ≥1%. CMD was defined as coronary flow reserve to intracoronary adenosine of ≤2. Major adverse cardiovascular events considered were myocardial infarction, coronary revascularization, or stroke. RESULTS: A total of 177 participants were examined. Mean follow-up was 12±7 years. A total of 17 patients had CHIP and 28 had CH. Cases with CMD (n=19) were compared with controls with no CMD (n=158). Cases were 56±9 years, were 68% women, and had more CHIP (27%; P=0.028) and CH (42%; P=0.001) than controls. CMD was associated with independent risk for major adverse cardiovascular events (hazard ratio, 3.89 [95% CI, 1.21-12.56]; P=0.023), and 32% of this risk was mediated by CH. The risk mediated by CH was ≈0.5× as large as the direct effect of CMD on major adverse cardiovascular events. CONCLUSIONS: In humans, we observe patients with CMD are more likely to have CHIP, and nearly one-third of major adverse cardiovascular events in CMD are mediated by CH.

Clinical and molecular correlates of somatic and germline DDX41 variants in patients and families with myeloid neoplasms.

The diagnosis of germline predisposition to myeloid neoplasms (MN) secondary to DDX41 variants is currently hindered by the long latency period, variable family histories and the frequent occurrence of DDX41 variants of uncertain significance (VUS). We reviewed 4,524 consecutive patients who underwent targeted sequencing for suspected or known MN and analyzed the clinical impact and relevance of DDX41VUS in comparison to DDX41path variants. Among 107 patients (44 [0.9%] DDX41path and 63 DDX41VUS [1.4%; 11 patients with both DDX41path and DDX41VUS]), we identified 17 unique DDX41path and 45 DDX41VUS variants: 24 (23%) and 77 (72%) patients had proven and presumed germline DDX41 variants, respectively. The median age was similar between DDX41path and DDX41VUS (66 vs. 62 years; P=0.41). The median variant allele frequency (VAF) (47% vs. 48%; P=0.62), frequency of somatic myeloid co-mutations (34% vs 25%; P= 0.28), cytogenetic abnormalities (16% vs. 12%; P=>0.99) and family history of hematological malignancies (20% vs. 33%; P=0.59) were comparable between the two groups. Time to treatment in months (1.53 vs. 0.3; P=0.16) and proportion of patients progressing to acute myeloid leukemia (14% vs. 11%; P=0.68), were similar. The median overall survival in patients with high-risk myelodysplastic syndrome/acute myloid leukemia was 63.4 and 55.7 months in the context of DDX41path and DDX41VUS, respectively (P=0.93). Comparable molecular profiles and clinical outcomes among DDX41path and DDX41VUS patients highlights the need for a comprehensive DDX41 variant interrogation/classification system, to improve surveillance and management strategies in patients and families with germline DDX41 predisposition syndromes.

Patients with telomere biology disorders show context specific somatic mosaic states with high frequency of U2AF1 variants.

Somatic mosaic states in telomere biology disorders are characterized by somatic variants in the spliceosome and DNA damage response and repair pathways. A likely maladaptive response to short telomeres that may lead to increased hematological cancer.

Mutation-enhanced international prognostic systems for essential thrombocythaemia and polycythaemia vera.

Survival prediction in essential thrombocythaemia (ET) and polycythaemia vera (PV) is currently based on clinically-derived variables; we examined the possibility of integrating genetic information for predicting survival. To this end, 906 molecularly-annotated patients (416 Mayo Clinic; 490 University of Florence, Italy), including 502 ET and 404 PV, were recruited. Multivariable analysis identified spliceosome mutations to adversely affect overall (SF3B1, SRSF2 in ET and SRSF2 in PV) and myelofibrosis-free (U2AF1, SF3B1 in ET) survival; TP53 mutations predicted leukaemic transformation in ET; "adverse" mutations occurred in 51 (10%) ET and 8 (2%) PV patients. We confirmed the independent survival effect of adverse mutations [hazard ratio (HR) 2·4, 95% CI 1·6-3·5], age >60 years (6·6, 4·6-9·7), male sex (1·8, 1·3-2·4) and leukocytosis ≥11 × 109 /l (1·6, 1·1-2·2), in ET, and adverse mutations (7·8, 3·1-17·0), age >67 years (5·4, 3·6-8·1), leukocytosis ≥15 × 109 /l (2·8, 1·8-4·2) and thrombosis history (2·0, 1·4-2·9), in PV. HR-based risk point allocation allowed development of three-tiered mutation-enhanced international prognostic systems (MIPSS) which were validated in both cohorts and performance was shown to be superior to conventional scoring systems. Spliceosome mutations enhance survival prediction in ET and PV and identify patients at risk for fibrotic progression. TP53 mutations predict leukaemic transformation in ET.

The germline JAK2 GGCC (46/1) haplotype and survival among 414 molecularly-annotated patients with primary myelofibrosis.

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.

20+ Years and alive with primary myelofibrosis: Phenotypic signature of very long-lived patients.

In 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.

Suboptimal response rates to hypomethylating agent therapy in chronic myelomonocytic leukemia; a single institutional study of 121 patients.

Hypomethylating agents (HMA) are currently the only FDA approved therapy for patients with chronic myelomonocytic leukemia (CMML). In the current retrospective study, we assessed response rates as adjudicated by the IWG (International Working Group) MDS (myelodysplastic syndrome) and MDS/MPN myeloproliferative neoplasm overlap syndrome response criteria, in 121 CMML patients treated with Azacitidine (AZA, n = 56) and Decitabine (DAC, n = 65). The overall response rates were 41% by the IWG MDS (AZA- 45%, DAC-39%), and 56% by the IWG MDS/MPN (AZA-56%, DAC-58%) response criteria, with CR (complete remission) rates of <20% for both agents, by both criteria. There were no significant differences in response rates between proliferative and dysplastic CMML. Moreover, 29% of CMML patients in a CR with HMA progressed to AML (blast transformation), underscoring the limited impact of these agents on disease biology. Progression after HMA response was associated with a median overall-survival (OS) of 8 months, while median OS in patients with primary HMA failure was 4 months. Lower serum LDH levels (<250 Units/L) were associated with HMA responses by both criteria; while ASXL1 and TET2 mutational status had no impact. HMA treated patients had a longer median OS (31 vs 18 months; P = .01), in comparison to those treated with conventional care regimens (excluding observation only patients), without any differences between AZA vs DAC (P = .37). In conclusion, this study highlights the inadequacies of HMA therapy in CMML, retrospectively validates the IWG MDS/MPN response criteria and underscores the need for newer, rationally derived therapies.

A Pilot Study of the Telomerase Inhibitor Imetelstat for Myelofibrosis.

BACKGROUND: Current drugs for myeloproliferative neoplasm-associated myelofibrosis, including Janus kinase (JAK) inhibitors, do not induce complete or partial remissions. Imetelstat is a 13-mer lipid-conjugated oligonucleotide that targets the RNA template of human telomerase reverse transcriptase. METHODS: We sought to obtain preliminary information on the therapeutic activity and safety of imetelstat in patients with high-risk or intermediate-2-risk myelofibrosis. Imetelstat was administered as a 2-hour intravenous infusion (starting dose, 9.4 mg per kilogram of body weight) every 1 to 3 weeks. The primary end point was the overall response rate, and the secondary end points were adverse events, spleen response, and independence from red-cell transfusions. RESULTS: A total of 33 patients (median age, 67 years) met the eligibility criteria; 48% had received prior JAK inhibitor therapy. A complete or partial remission occurred in 7 patients (21%), with a median duration of response of 18 months (range, 13 to 20+) for complete responses and 10 months (range, 7 to 10+) for partial responses. Bone marrow fibrosis was reversed in all 4 patients who had a complete response, and a molecular response occurred in 3 of the 4 patients. Response rates were 27% among patients with a JAK2 mutation versus 0% among those without a JAK2 mutation (P=0.30) and 32% among patients without an ASXL1 mutation versus 0% among those with an ASXL1 mutation (P=0.07). The rate of complete response was 38% among patients with a mutation in SF3B1 or U2AF1 versus 4% among patients without a mutation in these genes (P=0.04). Responses did not correlate with baseline telomere length. Treatment-related adverse events included grade 4 thrombocytopenia (in 18% of patients), grade 4 neutropenia (in 12%), grade 3 anemia (in 30%), and grade 1 or 2 elevation in levels of total bilirubin (in 12%), alkaline phosphatase (in 21%), and aspartate aminotransferase (in 27%). CONCLUSIONS: Imetelstat was found to be active in patients with myelofibrosis but also had the potential to cause clinically significant myelosuppression. (Funded by Geron; ClinicalTrials.gov number, NCT01731951.).

Mutations and karyotype predict treatment response in myelodysplastic syndromes.

We examined the influence of mutations and karyotype on conventional treatment response, specifically hematological improvement in anemia, in primary myelodysplastic syndromes (MDS). Cytogenetic and next generation sequencing (NGS)-derived mutation information was available in 357 patients (median age 74 years; 70% males); the revised international prognostic scoring system risk distribution was very high in 11%, high 15%, intermediate 17%, low 40% and very low 16%. At least one mutation was detected in 81% of patients; most frequent were SF3B1 (32%), ASXL1 (27%), TET2 (24%) and U2AF1 (15%). At median follow-up of 24 months, treatment with hypomethylating agents (HMAs) was documented in 121 (34%) patients, lenalidomide (LEN) in 55 (15%), and erythropoiesis stimulating agents (ESAs) in 136 (38%). ASXL1 mutations adversely affected response to HMAs (27% vs 48%; P = 0.02) and LEN (9% vs 43%; P = 0.04), but not ESAs (P = 0.6). LEN response was also adversely affected by U2AF1 mutations (0% vs 42%; P = 0.02) and high risk karyotype (0% vs 41% in intermediate vs 47% in low risk; P = 0.01). Patients with SF3B1 mutations were more likely to respond to LEN (56% vs 27%; P = 0.04). Contrary to previous reports, we found no association between TET2 mutations and HMA treatment response (40% vs 41%; P = 0.9), even in the absence of ASXL1 mutations (P = 0.4).We conclude that ASXL1 mutations in MDS predict inferior response to treatment with both HMAs and LEN; response to LEN was also compromised by U2AF1 mutations and high risk karyotype; SF3B1 mutations identified patients likely to respond to LEN.

Splenectomy in patients with chronic myelomonocytic leukemia: Indications, histopathological findings and clinical outcomes in a single institutional series of thirty-nine patients.

In a 28-year period, 39 (7%) patients with chronic myelomonocytic leukemia (CMML) (median age 66 years, 64% male) underwent a splenectomy at our institution. Primary indications for splenectomy were refractory thrombocytopenia (36%), progressive spleen related symptoms (33%), emergent splenectomy for splenic rupture (21%), refractory anemia (8%), and prior to allogeneic stem cell transplant (3%). Eleven (28%) patients had anemia at the time of splenectomy, of which 3 (27%) were autoimmune. The median time to splenectomy from CMML diagnosis was 6 months (0-40); perioperative morbidity and mortality rates were 43% and 13%, while the median postsplenectomy survival was 25 months (11-38). Durable remission in spleen related symptoms, thrombocytopenia, complications from splenic rupture, and anemia were achieved in 85%, 50%, 62%, and 21% of patients, respectively. Perioperative morbidity (n = 30) included infections/sepsis in 6 (20%), intraabdominal bleeding in 4 (13%), venous thromboembolism (VTE) in 3 (10%), and acute lung injury in 2 (7%) patients. The median duration of hospital stay was 6 days (1-25), with 5 deaths occurring secondary to respiratory failure (n = 2), multiorgan dysfunction (n = 2) and hemorrhagic shock (n = 1). There was no difference in overall survival between CMML patients that underwent splenectomy, in comparison to those that did not. Unlike in myelofibrosis, portal hypertension was not an indication for splenectomy and no patients developed post-splenectomy thrombocytosis. In conclusion, apart from being a lifesaving emergent modality in the event of splenic rupture, splenectomy has an important palliative role in patients with CMML, with significant and durable improvements in spleen related symptoms and refractory cytopenias.

Therapy related-chronic myelomonocytic leukemia (CMML): Molecular, cytogenetic, and clinical distinctions from de novo CMML.

Therapy related myeloid neoplasms (t-MN) including therapy related myelodysplastic syndromes (t-MDS) and acute myeloid leukemia (t-AML) are associated with aggressive disease biologies and poor outcomes. In this large (n = 497) and informative (inclusive of molecular and cytogenetic information) chronic myelomonocytic leukemia (CMML) patient cohort, we demonstrate key biological insights and an independent prognostic impact for t-CMML. T-CMML was diagnosed in 9% of patients and occurred approximately 7 years after exposure to prior chemotherapy and/or radiation therapy. In comparison to de novo CMML, t-CMML patients had higher LDH levels, higher frequency of karyotypic abnormalities and had higher risk cytogenetic stratification. There were no differences in the distribution of gene mutations and unlike t-MDS/AML, balanced chromosomal translocations, abnormalities of chromosome 11q23 (1%) and Tp53 mutations (<2%) were uncommon. Molecularly integrated CMML prognostic models were not effective in risk stratifying t-CMML patients and responses to hypomethylating agents were dismal with no complete responses. Median overall (OS) and leukemia free survival (LFS) was shorter for t-CMML in comparison to d-CMML (Median OS 10.9 vs 26 months and median LFS 50 vs 127 months) and t-CMML independently and adversely impacted OS (P = .0001 HR 2.1 95% CI 1.4-3.0). This prognostic impact was retained in the context of the Mayo Molecular Model (P = .001, HR 2.4, 95% CI 1.5-3.7) and the GFM prognostic model (P < .0001, HR 2.15, 95% CI 1.5-3.7). In summary, we highlight the unique genetics and independent prognostic impact of t-CMML, warranting its inclusion as a separate entity in the classification schema for both CMML and t-MN.

Myeloproliferative neoplasms in the young: Mayo Clinic experience with 361 patients age 40 years or younger.

Between 1967 and 2017, 361 patients with myeloproliferative neoplasms (MPN), age ≤ 40 years, were seen at our institution, constituting 12% of all MPN patients (n = 3023) seen during the same time period; disease-specific incidences were 12% in polycythemia vera (PV; n = 79), 20% in essential thrombocythemia (ET; n = 219) and 5% in primary myelofibrosis (PMF; n = 63). Compared to their older counterparts, younger patients were more likely to present with low risk disease (P < .001) and display female preponderance in ET (P = .04), lower incidence of arterial events overall (P < .001), and higher incidence of venous thrombosis in PV (P = .01). Younger patients were also more likely to express CALR mutations, in ET and PMF, normal karyotype, in PV and PMF, and lower incidence of high molecular risk mutations in PMF (P significant in all instances). Over median follow-up of 11.3, 13, and 7.1 years for PV, ET, and PMF, leukemic transformations were respectively documented in 4%, 2%, and 10% (P values 0.1-0.9) while incidences of fibrotic progression in PV (22%) and ET (16%) were expectedly higher in young patients, because of their longer survival (P < .001). Median survival in young patients was 37 years for PV, 35 for ET and 20 for PMF; the corresponding values were 22, 22, and 8 years for ages 41-60 years and 10, 11, and 3 years for ages >60 years (P < .001). Young MPN patients comprise a unique disease subset defined by an attenuated-risk cytogenetic and mutational backdrop and conspicuously longer survival compared to their older counterparts, which requires assertion during patient counseling.

Mutations and prognosis in myelodysplastic syndromes: karyotype-adjusted analysis of targeted sequencing in 300 consecutive cases and development of a genetic risk model.

To develop a genetic risk model for primary myelodysplastic syndromes (MDS), we queried the prognostic significance of next-generation sequencing (NGS)-derived mutations, in the context of the Mayo cytogenetic risk stratification, which includes high-risk (monosomal karyotype; MK), intermediate-risk (non-MK, classified as intermediate/poor/very poor, per the revised international prognostic scoring system; IPSS-R), and low-risk (classified as good/very good, per IPSS-R). Univariate analysis in 300 consecutive patients with primary MDS identified TP53, RUNX1, U2AF1, ASXL1, EZH2, and SRSF2 mutations as "unfavorable" and SF3B1 as "favorable" risk factors for survival; for the purposes of the current study, the absence of SF3B1 mutation was accordingly dubbed as an "adverse" mutation. Analysis adjusted for age and MK, based on our previous observation of significant clustering between MK and TP53 mutations, confirmed independent prognostic contribution from RUNX1, ASXL1, and SF3B1 mutations. Multivariable analysis that included age, the Mayo cytogenetics risk model and the number of adverse mutations resulted in HRs (95% CI) of 5.3 (2.5-10.3) for presence of three adverse mutations, 2.4 (1.6-3.7) for presence of two adverse mutations, 1.5 (1.02-2.2) for presence of one adverse mutation, 5.6 (3.4-9.1) for high-risk karyotype, 1.5 (1.1-2.2) for intermediate-risk karyotype and 2.4 (1.8-3.3) for age >70 years; HR-weighted risk point assignment generated a three-tiered genetic risk model: high (N = 65; 5-year survival 2%), intermediate (N = 100; 5-year survival 18%), and low (N = 135; 5-year survival 56%). The current study provides a practically simple risk model in MDS that is based on age, karyotype, and mutations only.

Driver mutations and prognosis in primary myelofibrosis: Mayo-Careggi MPN alliance study of 1,095 patients.

The 2013 discovery of calreticulin (CALR) mutations in myeloproliferative neoplasms was attended by their association with longer survival in primary myelofibrosis (PMF). Subsequent studies have suggested prognostic distinction between type 1/like and type 2/like CALR mutations and detrimental effect from triple-negative mutational status. Among 709 Mayo Clinic patients with PMF, 467 (66%) harbored JAK2, 112 (16%) CALR type 1/like, 24 (3.4%) CALR type 2/like, 38 (5.4%) MPL mutations and 68 (10%) were triple-negative. Survival was longer with type 1/like CALR, compared to JAK2 (HR 2.6, 95% CI 1.9-3.5), type 2/like CALR (HR 2.5, 95% CI 1.4-4.5), MPL (HR 1.8, 95% CI 1.1-2.9) and triple-negative mutational status (HR 2.4, 95% CI 1.6-3.6), but otherwise similar between the non-type 1/like CALR mutational states (P = .41). In multivariable analysis, the absence of type 1/like CALR (P < .001; HR 2, 95% CI 1.4-2.7), presence of ASXL1/SRSF2 mutations (P < .001; HR 1.9, 95% CI 1.5-2.4) and DIPSS-plus (P < .001) were each predictive of inferior survival. Furthermore, among 210 patients with ASXL1/SRSF2 mutations, survival was significantly longer in the presence vs. absence of type 1/like CALR mutations (median 5.8 vs. 2.9 years; P < .001). Triple-negative status did not disclose additional prognostic information for overall or leukemia-free survival. The observations regarding the prognostic distinction between CALR mutation variants were validated in an external cohort of 386 patients from the University of Florence Careggi hospital. We conclude that type 1/like CALR mutations in PMF not only predict superior survival, but also partially amend the detrimental effect of high molecular risk mutations.