Therapy-related myeloid neoplasms with different latencies: a detailed clinicopathologic analysis.

Therapy-related myeloid neoplasm (t-MN) arising in patients with prior cytotoxic treatments is considered a distinct entity due to its unfavorable prognosis. Latencies between the initial cytotoxic therapy and the occurrence of t-MNs vary but usually fall between 1 and 10 years. t-MNs with unusually short or long latencies are not well characterized. It is unclear if they are biologically similar to the ones with ordinary latencies and should be kept in the t-MN entity. We compiled a cohort of t-MN cases including short (<1 year), ordinary (1-10 years), and extended (>10 years) latencies from two tertiary medical centers. Both the t-MNs with ordinary and extended latencies showed high likelihood of high-risk genetic abnormalities and demonstrated no significant survival differences. But the t-MNs with extended latencies were more likely associated with history of multiple cancers (p = 0.007) and were younger at the time of cytotoxic treatments (p < 0.001) when compared to the t-MNs with ordinary latencies. The t-MN with short latencies appears to be a very rare and highly heterogeneous group. In summary, the genetic composition appears similar in the t-MNs with ordinary and extended latencies. However, the association between the t-MN with extended latencies and history of multiple cancers raises a possibility that cancer predisposition may contribute to the accumulation of genetic abnormalities in these patients. Investigation into potential germline mutations in the t-MN patients with extended latencies may provide important information for related family members.

Genomic landscape of Epstein-Barr virus-positive extranodal marginal zone lymphomas of mucosa-associated lymphoid tissue.

Epstein-Barr virus (EBV)-positive extranodal marginal zone lymphomas of mucosa-associated lymphoid tissue (MALT lymphomas) were initially described in solid organ transplant recipients, and, more recently, in other immunodeficiency settings. The overall prevalence of EBV-positive MALT lymphomas has not been established, and little is known with respect to their genomic characteristics. Eight EBV-positive MALT lymphomas were identified, including 1 case found after screening a series of 88 consecutive MALT lymphomas with EBER in situ hybridization (1%). The genomic landscape was assessed in 7 of the 8 cases with a targeted high throughput sequencing panel and array comparative genomic hybridization. Results were compared to published data for MALT lymphomas. Of the 8 cases, 6 occurred post-transplant, 1 in the setting of primary immunodeficiency, and 1 case was age-related. Single pathogenic/likely pathogenic mutations were identified in 4 of 7 cases, including mutations in IRF8, BRAF, TNFAIP3, and SMARCA4. Other than TNFAIP3, these genes are mutated in <3% of EBV-negative MALT lymphomas. Copy number abnormalities were identified in 6 of 7 cases with a median of 6 gains and 2 losses per case, including 4 cases with gains in regions encompassing several IRF family or interacting genes (IRF2BP2, IRF2, and IRF4). There was no evidence of trisomies of chromosomes 3 or 18. In summary, EBV-positive MALT lymphomas are rare and, like other MALT lymphomas, are usually genetically non-complex. Conversely, while EBV-negative MALT lymphomas typically show mutational abnormalities in the NF-κB pathway, other than the 1 TNFAIP3-mutated case, no other NF-κB pathway mutations were identified in the EBV-positive cases. EBV-positive MALT lymphomas often have either mutations or copy number abnormalities in IRF family or interacting genes, suggesting that this pathway may play a role in these lymphomas.

Clinicopathologic Characterization of Hypocellular Acute Myeloid Leukemia (AML) Showed Fewer Genetic Abnormalities Involving Cell Proliferation and NPM1 When Compared With Nonhypocellular AML.

OBJECTIVES: Hypocellular acute myeloid leukemia (AML) is uncommon. Despite the prognostic and therapeutic importance of mutational analysis, the mutational landscape of hypocellular AML is not well understood. METHODS: We identified 25 patients with hypocellular AML, and 141 patients with nonhypocellular AML were identified as a control group. We applied next-generation sequencing for the first time to profile this entity. RESULTS: The hypocellular AML patients were older than those with nonhypocellular AML (P = .037). At diagnosis, hypocellular AML had lower leukocyte counts (P = .012), higher hemoglobin (P = .003), and lower blast counts in the peripheral blood (P < .001) and bone marrow (P = .003). Hypocellular AML was less likely to have mutations involving cell proliferation (P = .027) and NPM1 (P = .022) compared with nonhypocellular AML. Hypocellular AML showed a high incidence of spliceosomal mutations and myelodysplastic syndrome-defining chromosome abnormalities (65%), but the incidence was not significantly different from that in nonhypocellular AML. There was no significant survival difference between hypocellular and nonhypocellular AML. CONCLUSIONS: To our knowledge, this study is the first to demonstrate hypocellular AML showed fewer genetic alterations involving cell proliferation and NPM1 when compared directly with nonhypocellular AML; this finding likely contributes to the low marrow cellularity in at least a portion of the patients with hypocellular AML.

Comparison of Aortitis Versus Noninflammatory Aortic Aneurysms Among Patients Who Undergo Open Aortic Aneurysm Repair.

OBJECTIVE: Distinguishing aortitis-induced aneurysms from noninflammatory aortic aneurysms is difficult and often incidentally diagnosed on histologic examination after surgical repair. This study was undertaken to examine surgically diagnosed aortitis and identify patient characteristics and imaging findings associated with the disease. METHODS: In this case-control study, cases had newly diagnosed, biopsy-proven noninfectious aortitis after open thoracic aortic aneurysm surgical repair. Five controls were matched with cases for year of surgery and lacked significant inflammation on surgical pathology analysis. Data on comorbidities, demographic characteristics, and laboratory and imaging abnormalities prior to surgery were collected. Associations between exposures and outcomes were evaluated using conditional logistic regression. Backward stepwise logistic regression was used to determine factors independently associated with aortitis. Odds ratios (ORs) with 95%confidence intervals (95%CIs) were calculated. RESULTS: The study included 262 patients (43 patients with aortitis and 219 controls). Patients with aortitis were older at the time of surgery, predominantly female, and less likely to have a history of coronary artery disease (CAD). Multivariable analysis revealed that aortitis was independently associated with an older age at the time of surgery (OR 1.08 [95%CI 1.03-1.13], P < 0.01), female sex (OR 2.36 [95%CI 1.01-5.51], P = 0.04), absence of CAD (OR 6.92 [95%CI 2.14-22.34], P = 0.04), a larger aneurysm diameter (OR 1.74 [95%CI 1.02-2.98], P = 0.04), and arterial wall thickening on imaging (OR 56.93 [95%CI 4.31-752.33], P < 0.01). CONCLUSION: Among patients who undergo open surgical repair of an aortic aneurysm, elderly women with no history of CAD who have evidence of other aortic or arterial wall thickening on imaging are more likely to have histologic evidence of aortitis. Patients with these characteristics may benefit from further rheumatologic evaluation.

Acute myeloid leukemia with isolated del(5q) is associated with IDH1/IDH2 mutations and better prognosis when compared to acute myeloid leukemia with complex karyotype including del(5q).

Myelodysplastic syndrome with isolated del(5q) is a well-recognized entity with a relatively favorable prognosis. Isolated del(5q) in acute myeloid leukemia is rare and acute myeloid leukemia cases with isolated del(5q) are not well characterized. Del(5q) has been shown to be a poor prognostic marker in acute myeloid leukemia based on multivariable analysis in large cohort studies, which contained mostly cases with del(5q) in the context of multiple chromosomal abnormalities. To further characterize acute myeloid leukemia with isolated del(5q), clinicopathologic characterization including mutation analysis was performed. During a 10-year period, we identified 12 cases of acute myeloid leukemia with isolated del(5q), 7 cases of acute myeloid leukemia with del(5q) plus one additional chromosome abnormality not involving chromosome 7, as well as two control groups composed of 124 cases of acute myeloid leukemia with complex karyotype including del(5q), and 40 cases of myelodysplastic syndrome with isolated del(5q). At diagnosis, cases of acute myeloid leukemia with isolated del(5q) had higher platelet counts (p = 0.044), hemoglobin (p = 0.011), and mean corpuscular volume (p = 0.017) compared with cases of acute myeloid leukemia with complex karyotype including del(5q). Acute myeloid leukemia with isolated del(5q) was less likely therapy-related (p = 0.037), more likely to have IDH1/IDH2 mutations (p = 0.009), and less likely to have TP53 mutations (p = 0.005) when compared to acute myeloid leukemia with complex karyotype including del(5q). Acute myeloid leukemia with isolated del(5q) also showed longer overall survival than acute myeloid leukemia with complex karyotype cases including del(5q) (p = 0.004). In summary, acute myeloid leukemia with isolated del(5q) appeared to show some distinct clinicopathologic and genomic features as compared to cases of acute myeloid leukemia with complex karyotype including del(5q).

Identification of Clinically Relevant Mycobacterial Species After Extended Incubation Times in the BACTEC MGIT System.

Objectives: Traditionally, for mycobacterial culture both solid and broth media are used and routinely held for 6 weeks minimum to optimize yield. We retrospectively reviewed all positive mycobacterial cultures over a 12-month period to assess growth kinetics of clinically relevant isolates. Methods: From January to December 2015, 658 positive mycobacteria cultures by solid (7H11 and 7H10 plates) and/or broth (BACTEC MGIT) media were identified and reviewed. Results: In broth-only cultures, 21 of 153 (13.7%) from 21 patients were positive after 28 days' incubation. Subsequent chart review revealed the following species: 11 Mycobacterium avium intracellulare complex (MAI), five Mycobacterium tuberculosis (MTB), and five other non-MTB/MAI mycobacteria. Two of the cases of MTB were first-time isolates, and 11.4% of MTB-positive cultures became positive after 4 weeks' incubation. Conclusions: These data provide strong evidence reaffirming that clinically meaningful results are frequently detected after extended incubation times by broth-only methods, including several MTB isolates.

Role of high-throughput sequencing in the diagnosis of cutaneous T-cell lymphoma.

AIMS: Substantial clinicopathological overlap exists between cutaneous T-cell lymphoma (CTCL) and benign conditions, leading to diagnostic difficulties. We sought to delineate the utility of high-throughput sequencing (HTS) across a spectrum of histological findings in CTCL and reactive mimics. METHODS: One hundred skin biopsies obtained for clinical concern for CTCL were identified, comprising 25 cases each from four histological categories: 'definitive CTCL', 'atypical lymphoid infiltrate, concerning for CTCL', 'atypical lymphoid infiltrate, favour reactive' or 'reactive lymphoid infiltrate'. T-cell receptor gamma chain gene (TRG) PCR and T-cell receptor beta chain gene HTS were performed on both skin biopsy and concurrently collected peripheral blood; most peripheral blood samples were also analysed by flow cytometry. RESULTS: Histologically defined CTCL specimens had significantly higher clonality scores and T-cell fractions via HTS than all other groups (all p<0.002 and p<0.03, respectively). HTS was more diagnostically specific than TRG PCR in skin (100% vs 88%), while diagnostic sensitivity (68% vs 72%) and accuracy (84% vs 80%) were similar. TRG PCR and flow cytometry performed on blood were the least diagnostically useful assays. Some identically sized peaks detected by TRG PCR in concurrent skin and peripheral blood specimens were non-identical by HTS analysis. CONCLUSIONS: HTS, by assessing both clonality and T-cell fractions in skin biopsies, is a powerful tool to aid in the diagnosis of CTCL. It is more specific than TRG PCR in distinguishing definitive CTCL from reactive and indeterminate histology. Identically sized peaks by TRG PCR, typically interpreted to be clonally related, are not always clonally identical by sequencing.

A reevaluation of erythroid predominance in Acute Myeloid Leukemia using the updated WHO 2016 Criteria.

The 2016 WHO update changed the diagnostic criteria for myeloid neoplasms with erythroid predominance, limiting the diagnosis of acute myeloid leukemia to cases with ≥20% blasts in the bone marrow or peripheral blood. Although acute myeloid leukemia with ≥50% erythroid cells has historically been presumed to represent acute myeloid leukemia with myelodysplasia-related changes, this hypothesis has never been systematically examined. We sought to investigate the clinicopathologic, cytogenetic, and molecular features of acute myeloid leukemia with erythroid predominance to subclassify cases as defined by the 2016 WHO. We retrospectively identified patients with ≥50% erythroid precursors and either ≥20% bone marrow blasts or ≥20% peripheral blood blasts at the time of initial diagnosis at seven major academic centers. Laboratory and clinical data were obtained. Patients were then reclassified according to 2016 WHO guidelines. A matched control group was also obtained. We identified 146 patients with acute myeloid leukemia with erythroid predominance (62% M, average age: 62 y, range: 5-93 y). Of these, 91 were acute myeloid leukemia with myelodysplasia-related changes, 20 (14%) were therapy-related myeloid neoplasm, 23 (16%) acute myeloid leukemia, not otherwise specified, and ten acute myeloid leukemia with recurrent cytogenetic/molecular abnormalities. The bone marrow blast count ranged from 9-41%. There was no difference in survival for patients with erythroid predominance compared to patients with acute myeloid leukemia without erythroid proliferations. In a multivariable analysis, cytogenetic risk was the only significant predictor of survival. We find a significantly lower rate of FLT3 and RAS pathway alterations in acute myeloid leukemia with erythroid predominance compared to controls. Our study is one of the first to apply the 2016 WHO guidelines for classification of acute myeloid leukemia. We find acute myeloid leukemia with erythroid predominance is a heterogeneous group and that erythroid richness has no impact on overall survival.

Bone marrow morphology is a strong discriminator between chronic eosinophilic leukemia, not otherwise specified and reactive idiopathic hypereosinophilic syndrome.

Chronic eosinophilic leukemia, not otherwise specified can be difficult to distinguish from idiopathic hypereosinophilic syndrome according to the current World Health Organization guideline. To examine whether the morphological features of bone marrow might aid in the differential diagnosis of these two entities, we studied a total of 139 patients with a diagnosis of chronic eosinophilic leukemia, not otherwise specified (n=17) or idiopathic hypereosinophilic syndrome (n=122). As a group, abnormal bone marrow morphological features, resembling myelodysplastic syndromes, myeloproliferative neoplasm or myelodysplastic/myeloproliferative neoplasm, were identified in 40/139 (27%) patients: 16 (94%) of those with chronic eosinophilic leukemia and 24 (20%) of those with hypereosinophilic syndrome. Abnormal bone marrow correlated with older age (P<0.001), constitutional symptoms (P<0.001), anemia (P=0.041), abnormal platelet count (P=0.002), organomegaly (P=0.008), elevated lactate dehydrogenase concentration (P=0.005), abnormal karyotype (P<0.001), as well as the presence of myeloid neoplasm-related mutations (P<0.001). Patients with abnormal bone marrow had shorter survival (48.1 months versus not reached, P<0.001), a finding which was independent of other confounding factors (P<0.001). The association between abnormal bone marrow and shorter survival was also observed in hypereosinophilic syndrome patients alone. In summary, most patients with chronic eosinophilic leukemia, not otherwise specified and a proportion of those with idiopathic hypereosinophilic syndrome show abnormal bone marrow features similar to the ones encountered in patients with myelodysplastic syndromes, myelodysplastic/myeloproliferative neoplasm or BCR-ABL1-negative myeloproliferative neoplasm. Among patients who are currently considered to have idiopathic hypereosinophilic syndrome, abnormal bone marrow is a strong indicator of clonal hematopoiesis. Similar to other myeloid neoplasms, bone marrow morphology should be one of the major criteria to distinguish patients with chronic eosinophilic leukemia, not otherwise specified or clonal hypereosinophilic syndrome from those with truly reactive idiopathic hypereosinophilic syndrome.

Corynebacterium propinquum endocarditis: a confounding presentation of a rare entity.

Infective endocarditis is rarely caused by Corynebacterium species. We report a unique case of Corynebacterium propinquum endocarditis in an otherwise healthy individual, and it is the first example of this organism causing culture-negative endocarditis. Conflicting clinical and microbiological data led to the use of sequencing to confirm the causative organism. This case illustrates C. propinquum as a cause of infective endocarditis, and it demonstrates the utility of ancillary molecular diagnostic techniques to identify etiologic agents in difficult cases of infective endocarditis.

Evidence for heightened hexokinase II immunoexpression in hepatocyte dysplasia and hepatocellular carcinoma.

BACKGROUND: Normal hepatocytes exhibit low-affinity hexokinase (glucokinase [HKIV]), but during oncogenesis, there is a switch from HKIV to HKII expression. The aims of this study were to compare the immunoexpression of HKII in non-dysplastic cirrhosis (NDC), liver cell change/dysplasia in cirrhosis (LCD), HCC, and normal liver control tissues, and to correlate HKII expression with clinical and histopathological parameters. DESIGN: Immunohistochemistry was performed on a liver cancer progression tissue array consisting of specimens from explants with cirrhosis, including 45 tissue samples with HCC, 108 without HCC, 143 with LCD, and 8 normal liver control tissues. HKII expression was quantified as positive pixel counts/square millimeter (ppc/mm(2)) by image analysis. RESULTS: There was a stepwise increase in HKII level from normal liver tissue to NDC, to LCD, and to HCC (p = 0.001). HKII levels were significantly higher in areas of LCD versus NDC (p ≤ 0.001), and in LCD and HCC versus NDC (p = 0.007). HKII levels were similar in LCD and HCC (p = 0.124). HKII levels were higher in grade 2-4 versus grade 1 HCCs (p = 0.044), and in pleomorphic versus non-pleomorphic HCC variants (p = 0.041). Higher levels of HKII expression in LCD and HCC versus NDC and in higher tumor grade remained significant in multivariate analysis. CONCLUSIONS: Higher levels of HKII immunoexpression in LDC and HCC compared with NDC suggest that upregulation of HKII occurs during the process of hepatocarcinogenesis in humans. In HCC, higher levels of HKII are associated with more aggressive histological features.