AbstractBetween 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.
Practice‐relevant demarcation of systemic mastocytosis associated with another hematologic neoplasm
AbstractTrabectedin is an FDA‐approved DNA minor groove binder that has activity against translocation‐associated sarcomas. Lurbinectedin is a next‐generation minor groove binder with preclinical activity against myeloid leukemia cells. A dose‐finding phase 1 clinical trial was performed in patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) with further assessment of safety and tolerability. Forty‐two patients with relapsed/refractory AML/MDS received lurbinectedin administered as a 1‐hour intravenous infusion in a 3 + 3 study design. Two dosing schedules were used: 3.5, 5, 7, or 6 mg on days 1 and 8 or 2, 3, 1, or 1.5 mg for 3 consecutive days on days 1 to 3. Three patients experienced dose‐limiting toxicities of rhabdomyolysis (grade 4), hyperbilirubinemia (grade 3), and oral herpes (grade 3) with the day 1 and 8 schedule. Otherwise, adverse events mainly consisted of gastrointestinal manifestations (n = 11), febrile neutropenia/infections (n = 4), pulmonary toxicity (n = 2), and renal failure (n = 2). The most common laboratory abnormalities observed were an increase in creatinine (93%) and anemia, neutropenia, and thrombocytopenia (100%). Overall, 33 of 42 patients (79%) had reduction in blasts in peripheral blood or bone marrow. One patient achieved a partial response and 2 patients a morphologic leukemia‐free state. Most (n = 30, 71%) were discontinued due to progressive disease. Early deaths occurred from disease‐related causes that were not attributable to lurbinectedin. Four patients with a chromosome 11q21‐23 abnormality had significantly greater bone marrow blast reduction than those without such abnormality, with decrease of 31 ± 14% (n = 4) vs 8 ± 8% (n = 16), respectively (P = .04). Overall, lurbinectedin was safe and tolerated using the schedules and dose levels tested. While no sustained remissions were observed, single‐agent lurbinectedin was transiently leukemia suppressive for some patients.
Cytogenetic abnormalities in systemic mastocytosis: WHO subcategory‐specific incidence and prognostic impact among 348 informative cases
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.
Mutations and karyotype predict treatment response in myelodysplastic syndromes
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.
Splenectomy in patients with chronic myelomonocytic leukemia: Indications, histopathological findings and clinical outcomes in a single institutional series of thirty‐nine patients
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.
Primary myelofibrosis: 2019 update on diagnosis, risk‐stratification and management
AbstractDisease overviewPrimary myelofibrosis (PMF) is a myeloproliferative neoplasm (MPN) characterized by stem cell‐derived clonal myeloproliferation that is often but not always accompanied by JAK2, CALR, or MPL mutations; additional disease features include bone marrow stromal reaction including reticulin fibrosis, abnormal cytokine expression, anemia, hepatosplenomegaly, extramedullary hematopoiesis (EMH), constitutional symptoms, cachexia, leukemic progression, and shortened survival.DiagnosisDiagnosis of PMF is based on bone marrow morphology. Presence of JAK2, CALR, or MPL mutation, expected in ∼ 90% of the patients, is supportive but not essential for diagnosis. The revised 2016 World Health Organization (WHO) classification system distinguishes “prefibrotic” from “overtly fibrotic” PMF; the former might mimic ET in its presentation and it is prognostically relevant to distinguish the two.Risk stratificationTwo new prognostic systems for PMF have recently been introduced: GIPSS (genetically inspired prognostic scoring system) and MIPSS70+ version 2.0 (mutation‐ and karyotype‐enhanced international prognostic scoring system). GIPSS is based exclusively on mutations and karyotype. MIPSS70+ version 2.0 utilizes both genetic and clinical risk factors. GIPSS features four and MIPSS70+ version 2.0 five risk categories. MIPSS70+ version 2.0 requires an online score calculator (http://www.mipss70score.it) while GIPPS offers a lower complexity prognostic tool.Risk‐adapted therapyObservation alone is advised for MIPSS70+ version 2.0 “low” and “very low” risk disease (estimated 10‐year survival 56%‐92%); allogeneic stem cell transplant is the preferred treatment of choice for “very high” and “high” risk disease (estimated 10‐year survival 0‐13%); treatment‐requiring patients with intermediate‐risk disease (estimated 10‐year survival 30%) are best served by participating in clinical trials. All other treatment approaches, including the use of JAK2 inhibitors, are mostly palliative and should not be used in the absence of clear treatment indications. Conventional treatment for anemia includes androgens, prednisone, thalidomide and danazol, for symptomatic splenomegaly hydroxyurea and ruxolitinib and for constitutional symptoms ruxolitinib. Splenectomy is considered for drug‐refractory splenomegaly and involved field radiotherapy for nonhepatosplenic EMH and extremity bone pain.
Cytogenetic findings in WHO‐defined polycythaemia vera and their prognostic relevance