Isolated anemia in patients with large granular lymphocytic leukemia (LGLL).

Patients with large granular lymphocytic leukemia (LGLL) frequently present with neutropenia. When present, anemia is usually accompanied by neutropenia and/or thrombocytopenia and isolated anemia is uncommon. We evaluated a cohort of 244 LGLL patients spanning 15 years and herein report the clinicopathologic features of 34 (14%) with isolated anemia. The patients with isolated anemia showed a significantly male predominance (p = 0.001), a lower level of hemoglobulin (p < 0.0001) and higher MCV (p = 0.017) and were less likely to have rheumatoid arthritis (p = 0.023) compared to the remaining 210 patients. Of the 34 LGLL patients with isolated anemia, 13 (38%) presented with pure red cell aplasia (PRCA), markedly decreased reticulocyte count and erythroid precursors, and more transfusion-dependence when compared to non-PRCA patients. There was no other significant clinicopathologic difference between PRCA and non-PRCA patients. 32 patients were followed for a median duration of 51 months (6-199). 24 patients were treated (11/11 PRCA and 13/21 non-PRCA patients, p < 0.02). The overall response rate to first-line therapy was 83% [8/11 (72.7%) for PRCA, 12/13 (92.3%) for non-PRCA], including 14 showing complete response and 6 showing partial response with a median response duration of 48 months (12-129). Half of non-PRCA patients who were observed experienced progressive anemia. During follow-up, no patients developed neutropenia; however, 5/27 (18.5%) patients developed thrombocytopenia. No significant difference in overall survival was noted between PRCA and non-PRCA patients. In summary, this study demonstrates the unique features of LGLL with isolated anemia and underscores the importance of recognizing LGLL as a potential cause of isolated anemia, which may benefit from disease-specific treatment. LGLL patients with PRCA were more likely to require treatment but demonstrated similar clinicopathologic features, therapeutic responses, and overall survival compared to isolated anemia without PRCA, suggesting PRCA and non-PRCA of T-LGLL belong to a common disease spectrum.

Clinical Heterogeneity of the VEXAS Syndrome: A Case Series.

The objective of this study is to describe the clinical features and outcomes of patients with the newly defined vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic (VEXAS) syndrome. Nine men with somatic mutations in the UBA1 gene were identified; the most frequent variant was p.Met41Thr (7 of 9, 78%). The median age at VEXAS diagnosis was 74 (67, 76.5) years, and patients had a median duration of symptoms for 4 years before diagnosis. Refractory constitutional symptoms (88%), ear and nose chondritis (55%), and inflammatory arthritis (55%) were common clinical features. Vasculitis was noted in 44%. All patients had significantly elevated inflammatory markers and macrocytic anemia. Thrombocytopenia was present in 66% at diagnosis of VEXAS. Eight patients had bone marrow biopsies performed. All bone marrows were hypercellular, and there was vacuolization of the erythroid (100%) or myeloid precursors (75%). Glucocorticoids attenuated symptoms at prednisone doses ≥20 mg per day, but no other immunosuppressive agent showed consistent long-term control of disease. One patient with coexisting plasma-cell myeloma received plasma-cell-directed therapy with improvement of the inflammatory response, which is a novel finding. In conclusion, VEXAS syndrome is a clinically heterogeneous, treatment-refractory inflammatory condition caused by somatic mutation of the UBA1 gene. Patients often present with overlapping rheumatologic manifestations and persistent hematologic abnormalities. As such, internists and subspecialists, including pathologists, should be aware of this condition to avert diagnostic delay, now that the etiology of this syndrome is known.

Spectrum of hematological malignancies, clonal evolution and outcomes in 144 Mayo Clinic patients with germline predisposition syndromes.

Germline predisposition syndromes (GPS) result from constitutional aberrations in tumor suppressive and homeostatic genes, increasing risk for neoplasia in affected kindred. In this study, we present clinical and genomic data on 144 Mayo Clinic patients with GPS; 59 evaluated prospectively using an algorithm-based diagnostic approach in the setting of a dedicated GPS/ inherited bone marrow failure syndrome (IBMFS) clinic. Seventy-two (50%) patients had IBMFS (telomere biology disorders-32,Fanconi anemia-18, Diamond Blackfan Anemia - 11, congenital neutropenia-5, Schwachman-Diamond Syndrome-5 and Bloom Syndrome-1), 27 (19%) had GPS with antecedent thrombocytopenia (RUNX1-FPD-15, ANKRD26-6, ETV6-2, GATA1-1, MPL-3), 28 (19%) had GPS without antecedent thrombocytopenia (GATA2 haploinsufficiency-16, DDX41-10, CBL-1 and CEBPA-1) and 17 (12%) had general cancer predisposition syndromes (ataxia telangiectasia-7, heterozygous ATM variants-3, CHEK2-2, TP53-2, CDK2NA-1, NF1-1 and Nijmegen Breakage Syndrome-1). Homozygous and heterozygous ATM pathogenic variants were exclusively associated with lymphoproliferative disorders (LPD), while DDX41 GPS was associated with LPD and myeloid neoplasms. The use of somatic NGS-testing identified clonal evolution in GPS patients, with ASXL1, RAS pathway genes, SRSF2 and TET2 being most frequently mutated. Fifty-two (91%) of 59 prospectively identified GPS patients had a change in their management approach, including additional GPS-related screening in 42 (71%), referral for allogenic HSCT workup and screening of related donors in 16 (27%), medication initiation and selection of specific conditioning regimens in 14 (24%), and genetic counseling with specific intent of fertility preservation and preconceptual counseling in 10 (17%) patients; highlighting the importance of dedicated GPS screening, detection and management programs for patients with hematological neoplasms.

Genetic and Clinical Studies of Patients With Increased Multinucleated Megakaryocytes in Bone Marrow as an Isolated Finding: A Diagnostic Pitfall for Myelodysplastic Syndrome.

The presence of increased multinucleated megakaryocytes (aka osteoclast-like) is considered a dysplastic feature in myelodysplastic syndrome; however, its clinical significance in isolation is uncertain. Herein, we report the clinicopathologic and genetic features of 18 such cases of 40,539 bone marrow biopsies spanning 10 years. All 18 patients had ≥25% multinucleated megakaryocytes in otherwise normal bone marrow biopsies, which were evaluated for plasma cell neoplasms (n=9), lymphoma (n=4), or anemia/neutropenia (n=5). None of the 17 patients tested showed acquired cytogenetic abnormalities. Sixteen patients underwent targeted gene panel next-generation sequencing: 9 patients had no pathogenic mutations; 3 harbored a single pathogenic mutation with variant allele frequencies of 7.5%, 7.6%, and 10.7%, likely representing clonal hematopoiesis of indeterminate potential; 1 had 2 pathogenic mutations, 1 of which had a variant allele frequency >20%. Fourteen of 18 patients had a follow-up period >6 months (median: 36.5 mo, range: 7 to 110 mo) and no patients developed a new-onset cytopenia, a progressive cytopenia, or a myeloid neoplasm. The patient with 2 mutations had persistent anemia, worrisome for an emerging MDS. However, given the absence of thrombocytopenia, increased multinucleated megakaryocytes in this patient could be an unrelated incidental finding. Our study indicates that increased multinucleated megakaryocytes as an isolated finding is a rare phenomenon, and this sole morphologic finding is not diagnostic of myelodysplastic syndrome. Diagnostic approaches in the presence of increased multinucleated megakaryocytes are proposed based on different clinical and pathologic scenarios.

Pathologic Spectrum and Molecular Landscape of Myeloid Disorders Harboring SF3B1 Mutations.

OBJECTIVES: SF3B1 mutations are the most common mutations in myelodysplastic syndromes (MDS). The International Working Group for the Prognosis of MDS (IWG-PM) recently proposed SF3B1-mutant MDS (SF3B1-mut-MDS) as a distinct disease subtype. We evaluated the spectrum and molecular landscape of SF3B1-mutated myeloid disorders and assessed the prognostication in MDS harboring SF3B1 mutations (MDS-SF3B1). METHODS: Cases were selected by retrospective review. Clinical course and laboratory and clinical findings were collected by chart review. SF3B1-mut-MDS was classified following IWG-PM criteria. RESULTS: SF3B1 mutations were identified in 75 of 955 patients, encompassing a full spectrum of myeloid disorders. In MDS-SF3B1, Revised International Prognostic Scoring System (IPSS-R) score greater than 3 and transcription factor (TF) comutations were adverse prognostic markers by both univariate and multivariate analyses. We confirmed the favorable outcome of IWG-PM-defined SF3B1-mut-MDS. Interestingly, it did not show sharp prognostic differentiation within MDS-SF3B1. CONCLUSIONS: SF3B1 mutations occur in the full spectrum of myeloid disorders. We independently validated the favorable prognostication of IWG-PM-defined SF3B1-mut-MDS. However it may not provide sharp prognostication within MDS-SF3B1 where IPSS-R and TF comutations were prognostic-informative. Larger cohort studies are warranted to verify these findings and refine MDS-SF3B1 prognostication.

Hemoglobin S/Hemoglobin Quebec-Chori Presenting as Sickle Cell Disease: A Case Report.

BACKGROUND: Sickle cell disease is a homozygous hemoglobinopathy with vaso-occlusive complications secondary to abnormal sickling of red blood cells under stressful conditions such as hypoxia. Children with sickle cell trait have a heterozygous genetic state, typically without symptoms. OBSERVATION: An 8-year-old boy diagnosed with sickle cell trait was found to have multiple complications consistent with sickle cell disease, including pain crises, osteomyelitis, and priapism. Over a 6-year period, he underwent routine laboratory evaluations without a definitive diagnosis. The diagnosis of a compound heterozygous state of hemoglobin S/hemoglobin Quebec-Chori was eventually made on the basis of mass spectrometry and confirmed with hemoglobin subunit beta gene sequencing. CONCLUSION: Expanding diagnostic evaluation in patients with abnormal clinical presentations is vital to making the correct diagnosis and hence earlier institution of appropriate management of rare hemoglobinopathies.

Secondary acquisition of BCR-ABL1 fusion in de novo GATA2-MECOM positive acute myeloid leukemia with subsequent emergence of a rare KMT2A-ASXL2 fusion.

Secondary acquisition of t(9;22)(q34;q11.2)/BCR-ABL1 fusion in the context of de novo acute myeloid leukemia (AML) with inv(3)(q21q26)/GATA2-MECOM rearrangement has been rarely reported. Furthermore, t(2;11)(p23;q23)/KMT2A-ASXL2 fusion has been rarely described with only a single case reported to date. We report a 45-year-old male with a diagnosis of de novo AML harboring GATA2-MECOM rearrangement in conjunction with a related subclone with concomitant inv(3) and t(9;22). The patient was treated with a tyrosine kinase inhibitor (TKI) which lead to disappearance of the inv(3)/t(9;22) subclone and subsequent expansion of the inv(3) ancestral clone. The patient was started on a 7+3 induction regimen with TKI but had persistent disease. He was placed on several additional treatment protocols and only achieved morphologic remission with a combination of fludarabine, cytarabine and filgrastim with TKI. Approximately 11.5 months after diagnosis the patient relapsed with the inv(3) clone predominating initially, followed by return of the inv(3)/t(9;22) subclone and the emergence of a second subclone with concomitant inv(3) and t(2;11)(p23;q23). Mate-pair sequencing was performed and identified a KMT2A-ASXL2 in-frame fusion, which was only recently described in a single case of therapy-related AML. For BCR-ABL1 positive AML, which generally carries a poor prognosis, treatment with TKIs has been proposed in combination with standard chemotherapy. In our case, treatment with TKI alone led to initial response of the BCR-ABL1 positive clone, but the ancestral clone quickly expanded and subsequent standard AML therapy may have led to further clonal evolution and re-emergence of the BCR-ABL1 clone in the absence of therapeutic selection.

The significance of genetic mutations and their prognostic impact on patients with incidental finding of isolated del(20q) in bone marrow without morphologic evidence of a myeloid neoplasm.

Patients with a sole del(20q) chromosomal abnormality and without morphologic features of a myeloid neoplasm (MN) have shown variable clinical outcomes. To explore the potential risk stratification markers in this group of patients, we evaluated their genetic mutational landscape by a 35-gene MN-focused next-generation sequencing (NGS) panel and examined the association of mutations to progression of MNs. Our study included 56 patients over a 10-year period with isolated del(20q), of whom 23 (41.1%) harbored at least one mutation. With a median follow-up of 32.6 months (range: 0.1-159.1), 9 of 23 patients with mutation(s) progressed to MNs, while all 33 patients without mutations did not progress to MN. Kaplan-Meier survival analysis demonstrated the presence of mutation(s) as a significant risk factor for progression to MN (P < 0.0001). MN progression was strongly associated with the presence of non-DNMT3A/TET2/ASXL1 epigenetic modifiers and nonspliceosome mutations (P = 0.003). There was no significant difference among patients with and without MN progression with respect to the number of mutations, variant allele frequency, percentage of del(20q), and other clinical/laboratory variables. This study illustrates the underlying genetic heterogeneity and complexity of isolated del(20q), and underscores the prognostic value of NGS mutational analysis in these cases.

Correction to: Hybridization capture-based next-generation sequencing reliably detects FLT3 mutations and classifies FLT3-internal tandem duplication allelic ratio in acute myeloid leukemia: a comparative study to standard fragment analysis.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Hybridization capture-based next generation sequencing reliably detects FLT3 mutations and classifies FLT3-internal tandem duplication allelic ratio in acute myeloid leukemia: a comparative study to standard fragment analysis.

FLT3-internal tandem duplication occurs in 20-30% of acute myeloid leukemia and confers an adverse prognosis with its allelic ratio being a key risk stratifier. The US Food and Drug Administration recently approved FLT3 inhibitors midostaurin and gilteritinib in FLT3 mutation-positive acute myeloid leukemia. Historically, FLT3 was tested by fragment analysis, which has become the standard method endorsed by international guidelines. However, next generation sequencing is increasingly used at acute myeloid leukemia diagnosis given its ability to simultaneously evaluate multiple clinically informative markers. As FLT3-internal tandem duplication detection was known to be challenging by next generation sequencing and the results carry profound prognostic and therapeutic implications, it is important to thoroughly examine its performance in FLT3-internal tandem duplication detection and allelic ratio classification. In a comparative study with fragment analysis, we retrospectively reviewed our experience using a custom-designed, hybridization capture-based, targeted next generation sequencing panel. Among 7902 cases, FLT3-internal tandem duplication was detected in 335 with variable sizes (3-231 bp) and insertion sites. Fragment analysis was also performed in 402 cases, demonstrating 100% concordance in FLT3-internal tandem duplication detection. In 136 dual-tested, positive cases, 128/136 (94%) exhibited concordant high/low allelic ratio classifications. The remaining 6% showed borderline low allelic ratio by next generation sequencing. The two methods were concordant in FLT3-tyrosine kinase domain mutation detection at the hotspot D835/I836 targeted by fragment analysis. Furthermore, seven mutations which may benefit from FLT3 inhibitor therapy were detected by next generation sequencing, in regions not covered by fragment analysis. Our study demonstrates that using a hybridization capture-based chemistry and optimized bioinformatics pipeline, next generation sequencing can reliably detect FLT3-internal tandem duplication and classify its allelic ratio for acute myeloid leukemia risk stratification. Next generation sequencing also exhibits superior comprehensiveness in FLT3 mutation detection and may further improve personalized, targeted therapy in acute myeloid leukemia.

Etiologies of Extreme Thrombocytosis: A Contemporary Series.

OBJECTIVE: To describe the multifactorial etiologies of extreme thrombocytosis (EXT) in different care settings and the frequency of finding an occult malignancy. PATIENTS AND METHODS: We conducted a retrospective chart review at Mayo Clinic from January 1, 2011, through December 31, 2016. Adult patients who had at least 2 readings of platelet counts greater than 1000×109/L within 30 days of each other were included. We determined the causes of EXT on the basis of preset definitions of precipitating factors and identified the dominant causes on the basis of the trend of platelet counts. RESULTS: A total of 44,490 patients had thrombocytosis, and 305 patients (0.7%) had EXT. In 242 patients (79.3%), EXT was multifactorial. Surgical complications (54.1%) and hematologic malignancies (27.9%) were the 2 most dominant causes. Thirty-eight patients (12.5%) had new diagnoses of malignancies, mostly myeloproliferative neoplasms. In inpatients, surgical complications (71.9%), concurrent/previous splenectomy (50.5%), and infections (44.9%) were the most common causes, whereas hematologic malignancies (56.9%), iron deficiency (36.7%), and previous splenectomy (28.4%) were the most common causes in outpatients. Hematologic malignancy was 3.4 times more likely to be the cause of EXT in outpatients than in inpatients (56.9% vs 16.8%), and a new diagnosis of hematologic malignancy was 1.9 times more likely to be made in outpatients (15.6% vs 8.2%). Eighty-four percent of patients had resolution of EXT within 30 days. One patient died during the period of EXT. Nonsurgical patients with hematologic malignancies had the most prolonged period of EXT. CONCLUSION: Extreme thrombocytosis is a multifactorial hematologic condition, and its etiology differs substantially between inpatients and outpatients. Occult hematologic malignancies are uncommon in EXT when other major causes are present.

Hepatosplenic γδ T-cell lymphoma of two adolescents: Case report and retrospective literature review in children, adolescents, and young adults.

HSTCL is a highly aggressive malignancy with a poor prognosis. Case series and accounts have reported the use of different chemotherapy regimens with diverse patient outcomes. Most long-term survivors had undergone high-dose chemotherapy with autologous or allogeneic HCT. We describe two pediatric patients with HSTCL who were treated with chemotherapy followed by allogeneic HCT. Both patients are alive and in complete remission 2 and 8 years after therapy. Multiagent chemotherapy followed with allogeneic HCT seems to provide patients who have chemotherapy-sensitive disease a long-term disease-free survival.

Clinical and laboratory characteristics in congenital ANKRD26 mutation-associated thrombocytopenia: A detailed phenotypic study of a family.

The clinical and laboratory characteristics of patients with non-syndromic, autosomal dominant thrombocytopenia secondary to germ line ANKRD26 mutations appear to be heterogeneous. Except for a targeted molecular genotyping approach, there is no distinct clinical or laboratory phenotype that has been specifically associated with this particular gene mutation. Such heterogeneity could be due to variations in mutation and genetic background in different families. To understand the phenotypic heterogeneity, we thoroughly studied one affected family using the International Society for Thrombosis and Haemostasis bleeding assessment tool and both clinically validated standard and esoteric platelet testing (electron microscopy (EM) and flow cytometry). We found that decreased platelet aggregation with arachidonic acid and epinephrine agonists was common in affected family members. EM studies demonstrated persistent borderline low mean dense granules per platelet, decreased alpha granules and an increased canalicular network pattern in all affected members. Since these characteristics are subtle or non-pathognomonic, molecular testing for ANKRD26 mutation remains the most reliable test to render a diagnosis and should be considered when evaluating a patient or family with congenital thrombocytopenia, particularly if there is a history of myeloid neoplasms.

PPP6R3-USP6 amplification: Novel oncogenic mechanism in malignant nodular fasciitis.

Nodular fasciitis (NF) is a clonal self-limited neoplastic proliferation characterized by rearrangements of the USP6 locus in most examples. To our knowledge well-documented malignant behavior has never been previously observed in NF. In this report we present an unusual case of NF with classical histologic features that showed a protracted clinical course characterized by multiple recurrences and eventual metastatic behavior over a period of 10 years. Molecular analyses revealed the presence and amplification of the novel PPPR6-USP6 gene fusion, which resulted in USP6 mRNA transcriptional upregulation. These findings further support the oncogenic role of the USP6 protease in mesenchymal neoplasia and expand the biologic potential of NF. © 2016 Wiley Periodicals, Inc.

Clinical course of patients with incidental finding of 20q- in the bone marrow without a morphologic evidence of myeloid neoplasm.

Deletion of the long arm of chromosome 20 (20q-) is a frequent finding in bone marrow karyotypes, mainly associated with myeloid neoplasms (MNs). Its clinical significance in the setting of normal bone marrow morphology is unclear. We described the clinical characteristics, cytogenetic findings, and outcome of 102 such patients seen at our institution from 2000-2014. Their median age was 66 years. The indication for bone marrow biopsy was either unexplained cytopenias (48%) or hematologic cancer staging/reevaluation (52%). In 88 (86%) patients, 20q- was an isolated finding. Thirty-nine (38%) patients previously received chemotherapy and 88 (86%) had cytopenias at the time of 20q- finding. After a median of 35 months, 12 (13%) patients developed MNs: 10 myelodysplastic syndromes, one acute myeloid leukemia and one myeloproliferative neoplasm. None of 14 patients with normal blood counts, but 7 of 35 (20%) with mild cytopenias, and 5 of 53 (9%) with moderate/severe cytopenias developed MNs. We did not find an association between the number of metaphases with 20q- and the development of MN. The incidental finding of 20q- in the bone marrow generally does not portend an early stage MN. Particularly, those without cytopenias at the time of diagnosis may have a good prognosis. Am. J. Hematol. 91:556-559, 2016. © 2016 Wiley Periodicals, Inc.

Impact of Alemtuzumab Therapy and Route of Administration in T-Prolymphocytic Leukemia: A Single-Center Experience.

OBJECTIVE: We conducted a single-center retrospective analysis to determine the impact of the anti-CD52 monoclonal antibody alemtuzumab including route of administration compared to non-alemtuzumab-containing regimens in T-prolymphocytic leukemia (T-PLL). PATIENTS AND METHODS: The study was a retrospective analysis of a consecutive cohort of adult patients diagnosed with T-PLL at Mayo Clinic Rochester from January 1, 1997, through September 30, 2014. RESULTS: A total of 41 patients were diagnosed with T-PLL per the World Health Organization 2008 classification. The median age was 66 years, and 23 (56%) were male. After a median follow-up of 18 months (range, 0.4-66.1 months), 32 patients (78%) had died, with a median overall survival of 16.9 months. Approximately half the cohort was treated with alemtuzumab, almost exclusively after 2004. Median survival for patients receiving intravenous alemtuzumab-based therapy was 40.5 versus 10.3 months for all other therapies (P = .0004). A significant survival difference between intravenous versus subcutaneous alemtuzumab administration of 40.5 versus 13.7 months was noted (P = .0014). Only 4 (14%) of 28 patients aged < 70 years underwent hematopoietic stem cell transplantation, with a median survival after transplantation of 4 months. CONCLUSION: In this large series of T-PLL patients treated at a single tertiary-care center, we confirmed the prior observation of the superiority of intravenous alemtuzumab over other therapies. Hematopoietic stem cell transplantation was feasible in a minority of potentially eligible patients. Early transplant referral should be considered for all eligible patients.