Patnaik, Mrinal

AbstractThe World Health Organization (WHO) system lists five morphological categories of systemic mastocytosis (SM): indolent (ISM), smoldering, SM with an associated hematological neoplasm (SM‐AHN), aggressive (ASM) and mast cell leukemia (MCL). Recent studies have highlighted the prognostic importance of mutations in SM, including ASXL1, RUNX1, and SRSF2. In contrast, information on incidence of cytogenetic abnormalities in SM and their prognostic relevance, especially in the context of mutations, is limited. In the current study, we retrospectively reviewed the cytogenetic findings in 348 consecutive cases of SM (median age 59 years; 53% males); 41% constituted ISM, 45% SM‐AHN, 14% ASM and two cases of MCL. Karyotype was abnormal in 53 (15%) cases with incidences of 6% for ISM, 26% for SM‐AHN and 8% for ASM (P < .001); among SM‐AHN cases, abnormal karyotype incidences were 0% for SM‐AHN‐lymphoid and 28% for SM‐AHN‐myeloid (P < .001). Clinical correlative studies disclosed significant associations between abnormal karyotype and male sex (P = .002), age > 60 years (P = .04), thrombocytopenia (P < .001) and anemia (P < .001), but not with the presence of adverse mutations (P = .19). In univariate analysis, abnormal karyotype was associated with inferior survival (HR 3.0, 95% CI 2.0‐4.3), specifically confirmed for ASM (HR 4.9, 95% CI 1.1‐16.1) and SM‐AHN (HR 1.8, 95% CI 1.2‐2.7). Sample size adequacy allowed additional multivariable analysis in SM‐AHN‐myeloid, which disclosed independent prognostic contribution from adverse mutations (P = .003), anemia (P = .003) and thrombocytopenia (P = .001), but not from abnormal karyotype (P = .31). Our observations suggest that mutations are prognostically more relevant than karyotype in SM.

Abstract 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.

AbstractIn 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.

AbstractTo 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.

AbstractThe prognostic importance of genetic information in primary myelofibrosis (PMF) was recently highlighted in a study of over 1000 cytogenetically‐annotated patients; 5‐year survival rates were 8% for very high risk (VHR), 27% “unfavorable” and 45% “favorable” karyotype. The current study addresses the practice‐relevant question of whether or not allogeneic hematopoietic stem cell transplant (HCT) can overcome the detrimental survival effect of VHR or unfavorable karyotype. The study included 67 patients with PMF or secondary MF who received HCT at the Mayo Clinic and in whom pretransplant cytogenetic information was available. Dynamic international prognostic scoring system (DIPSS) risk distribution was 13% high, 66% intermediate‐2 and 21% intermediate‐1. Cytogenetic risk distribution was 11% VHR, 34% unfavorable and 55% favorable. At median post‐HCT follow‐up of 60 months for living patients (range 34‐170), 28 (42%) deaths were recorded. Five‐year survival was 62% and was not affected by VHR or unfavorable karyotype (P = .68). The salutary effect of HCT in patients with VHR or unfavorable karyotype was also apparent during analysis of a combined dataset that included a nontransplant cohort of 383 patients with PMF; multivariable analysis of the combined dataset (n = 450) resulted in HRs (95% CI) of 2.4 (1.6‐3.6) for absence of transplant, 3.3 (2.2‐4.8) for VHR karyotype, 1.6 (1.2‐2.1) for unfavorable karyotype, 2.9 (2.0‐4.2) for DIPSS high and 1.7 (1.4‐2.2) for DIPSS intermediate‐2. These observations were further confirmed by analysis of more stringently matched case‐control subset cohorts and provide the evidence for the therapeutic preference of HCT in cytogenetically high risk patients with MF.