Pathology Residents as Testing Personnel in the Hematology Laboratory.

Context.—: Clinical laboratories and the training of pathology residents are tightly regulated environments. Compliance with regulatory requirements must be addressed when developing entrustable professional activities (EPAs) for pathology residents.

Acute purpura fulminans-a rare cause of skin necrosis: A single-institution clinicopathological experience.

Background: Purpura fulminans, an uncommon syndrome of intravascular thrombosis with hemorrhagic infarction of the skin, is often accompanied by disseminated intravascular coagulation (DIC) and multi-organ failure, and may ultimately lead to death.

Methods: Herein, we document 13 skin biopsies from 11 adult patients with the clinical diagnosis of sepsis and confirmed histopathologic diagnosis of intravascular thrombosis and/or DIC, compatible with acute infectious purpura fulminans (AIPF). Detailed history and clinical examination were performed, and the lesions were correlated with histopathologic findings.

Quantification of the Effectiveness of a Residency Program Using the Resident In-Service Examination.

This study describes a quantitative tool in the assessment of residency programs, in which national ranking of residents after the resident in-service examination in postgraduate year 4 is compared to that in postgraduate year 1. The relationship between training and changes in ranking, resident in-service examination results before and after training in specific areas are also compared. To illustrate the use of this novel approach, data from a large residency program were analyzed.

Thrombocytosis and STAT5 activation in chronic myelogenous leukaemia are not associated with JAK2 V617F or calreticulin mutations.

Aims: Marked thrombocytosis is uncommon in chronic myelogenous leukaemia (CML) but may be associated with mutation of JAK2 V617F, calreticulin (CALR) and/or phospho-STAT5 (p-STAT5) activation in other myeloproliferative neoplasms (MPNs), particularly essential thrombocythaemia (ET). We investigated the JAK2 V617F, CALR and STAT5 activation status in patients with CML and thrombocytosis (CML-T) that mimicked ET, trying to identify a common mechanism for thrombocytosis in MPN.

Methods: Blood and bone marrow morphological findings were reviewed from seven CML-T, four otherwise typical CML and one CML in blast phase.

The prognostic significance of an inv(3)(q21q26.2) in addition to a t(9;22)(q34;q11.2) in patients treated with tyrosine kinase inhibitors.

In chronic myelogenous leukemia, BCR-ABL1 positive detection of cytogenetic abnormalities in addition to the t(9;22) is thought to portend a poor prognosis; however, not all abnormalities associated with the t(9;22) have the same impact. Inv(3) defines a group of aggressive neoplasms with poor response to conventional treatment options. In this study, four cases with the t(9;22) and inv(3) treated with tyrosine kinase inhibitors (TKI) were investigated.

Concurrent juvenile myelomonocytic leukemia and T-lymphoblastic lymphoma with a shared missense mutation in NRAS.

Single cases of B- and T-lymphoblastic leukemia/lymphoma occurring after remission of JMML, and JMML occurring after remission of B-lymphoblastic leukemia have been reported in the literature. We present a unique case of a child with concurrent JMML and T-lymphoblastic lymphoma in which an identical missense mutation in NRAS was found in both the neoplastic JMML and T-LBL cells. JMML has been considered a stem cell disorder, and our case provides additional molecular evidence for a stem cell lesion underlying the two different disease phenotypes.

Validation of fluorescence in situ hybridization using an analyte-specific reagent for detection of abnormalities involving the mixed lineage leukemia gene.

Context: Fluorescence in situ hybridization (FISH) is a molecular cytogenetic assay that is commonly used in laboratory medicine. Most FISH assays are not approved by the US Food and Drug Administration but instead are laboratory-developed tests that use analyte-specific reagents. Although several guidelines exist for validation of FISH assays, few specific examples of FISH test validations are available in the literature.

Evaluation of chronic lymphocytic leukemia by oligonucleotide-based microarray analysis uncovers novel aberrations not detected by FISH or cytogenetic analysis.

Background: Cytogenetic evaluation is a key component of the diagnosis and prognosis of chronic lymphocytic leukemia (CLL). We performed oligonucleotide-based comparative genomic hybridization microarray analysis on 34 samples with CLL and known abnormal karyotypes previously determined by cytogenetics and/or fluorescence in situ hybridization (FISH).

Results: Using a custom designed microarray that targets >1800 genes involved in hematologic disease and other malignancies, we identified additional cryptic aberrations and novel findings in 59% of cases.

College of American Pathologists/American College of Medical Genetics proficiency testing for constitutional cytogenomic microarray analysis.

Purpose: To evaluate the feasibility of administering a newly established proficiency test offered through the College of American Pathologists and the American College of Medical Genetics for genomic copy number assessment by microarray analysis, and to determine the reproducibility and concordance among laboratory results from this test.

Methods: Surveys were designed through the Cytogenetic Resource Committee of the two colleges to assess the ability of testing laboratories to process DNA samples provided and interpret results. Supplemental questions were asked with each Survey to determine laboratory practice trends.

Diagnostic yield of bone marrow and peripheral blood FISH panel testing in clinically suspected myelodysplastic syndromes and/or acute myeloid leukemia: a prospective analysis of 433 cases.

It is unclear how often and in what setting fluorescence in situ hybridization (FISH) panels for myelodysplastic syndrome (MDS)/acute myeloid leukemia (AML) provide additional information over metaphase cytogenetics alone. Furthermore, the usefulness of peripheral blood vs bone marrow FISH has also not been directly compared. We prospectively compared metaphase cytogenetics and FISH for -5/5q-, -7/7q-, +8, and 20q- in 433 cases of suspected MDS/AML.

Characterization of chromosome arm 20q abnormalities in myeloid malignancies using genome-wide single nucleotide polymorphism array analysis.

Deletion of the long arm of chromosome 20 is a common abnormality associated with myeloid malignancies. We characterized abnormalities of chromosome 20 as defined by metaphase cytogenetics (MC) in patients with myeloid neoplasms to define commonly deleted regions (CDR) and commonly retained regions (CRR) using genome-wide, high resolution single nucleotide polymorphism array (SNP-A) analysis. We reviewed the MC results of a cohort of 1,162 patients with myeloid malignancies, including myelodysplastic syndromes (MDS), MDS/myeloproliferative neoplasia (MDS/MPN), and acute myeloid leukemia (AML).

A rare trigger for macrophage activation syndrome.

Macrophage activation syndrome (MAS) is a disorder characterized by increased activation of mononuclear cells leading to phagocytosis of blood cell precursors in the bone marrow. We describe a case of MAS triggered by disseminated histoplasmosis occurring in a patient with Still's disease on long-term treatment with adalimumab.

FISH and SNP-A karyotyping in myelodysplastic syndromes: improving cytogenetic detection of del(5q), monosomy 7, del(7q), trisomy 8 and del(20q).

Cytogenetic aberrations identified by metaphase cytogenetics (MC) have important diagnostic, prognostic and therapeutic roles in myelodysplastic syndromes (MDS). Fluorescence in situ hybridization (FISH) complements MC by the ability to evaluate large numbers of both interphase and metaphase nuclei. However, clinically practical FISH strategies are limited to detection of known lesions.

Chromosomal lesions and uniparental disomy detected by SNP arrays in MDS, MDS/MPD, and MDS-derived AML.

Using metaphase cytogenetics (MC), chromosomal abnormalities are found in only a proportion of patients with myelodysplastic syndrome (MDS). We hypothesized that with new precise methods more cryptic karyotypic lesions can be uncovered that may show important clinical implications. We have applied 250K single nucleotide polymorphisms (SNP) arrays (SNP-A) to study chromosomal lesions in samples from 174 patients (94 MDS, 33 secondary acute myeloid leukemia [sAML], and 47 myelodysplastic/myeloproliferative disease [MDS/MPD]) and 76 controls.

Detection of cryptic chromosomal lesions including acquired segmental uniparental disomy in advanced and low-risk myelodysplastic syndromes.

Objectives: Using metaphase cytogenetics (MC), chromosomal defects can be detected in 40% to 60% of patients with myelodysplastic syndromes (MDS); cytogenetic results have a major impact on prognosis. We hypothesize that more precise methods of chromosomal analysis will detect new/additional cryptic lesions in a higher proportion of MDS patients.

Methods: We have applied single nucleotide polymorphism microarrays (SNP-A) to perform high-resolution karyotyping in MDS to determine gene copy number and detect loss of heterozygosity (LOH).

Severe TMD/AMKL with GATA1 mutation in a stillborn fetus with Down syndrome.

Background: A 34-year-old woman was referred for evaluation of a recent stillborn male fetus, gestational age 27 6/7 weeks, found to have congenital myeloid leukemia at autopsy. Autopsy findings included high weight for gestational age, hepatomegaly, and extensive intravascular leukemic infiltrates in the placenta, heart, liver, thymus, lung, kidneys, and brain. Genetic consultation and examination of photographs of the fetus revealed dysmorphic features.

Karyotypic identification of abnormal clones preceding morphological changes or occurring with no definite morphological features of myelodysplastic syndrome: a preliminary study.

The diagnosis of myelodysplastic syndrome (MDS) is difficult to establish based on morphologic features alone because dysplasia may not always be detectable and the presence of dysplasia is not itself evidence of clonal disorder. As a result, the detection of a clonal cytogenetic abnormality has a major role in difficult cases in regard to diagnosis and the recognition of morphological cytogenetic correlates. In an attempt to assess the frequency and characteristic type of abnormal clones when it is not clear whether or not a hematological condition is neoplastic, cytogenetics have been analyzed necessarily in 159 patients with unexplained cytopenia or suspected MDS.

High-resolution genomic arrays facilitate detection of novel cryptic chromosomal lesions in myelodysplastic syndromes.

Objective: Unbalanced chromosomal aberrations are common in myelodysplastic syndromes and have prognostic implications. An increased frequency of cytogenetic changes may reflect an inherent chromosomal instability due to failure of DNA repair. Therefore, it is likely that chromosomal defects in myelodysplastic syndromes may be more frequent than predicted by metaphase cytogenetics and new cryptic lesions may be revealed by precise analysis methods.

Refractory anemia with ringed sideroblasts associated with marked thrombocytosis (RARS-T), another myeloproliferative condition characterized by JAK2 V617F mutation.

JAK2 V617F mutation recently was identified as a pathogenic factor in typical chronic myeloproliferative diseases (CMPD). Some forms of myelodysplastic syndromes (MDS) show a significant overlap with CMPD (classified as MDS/MPD), but the diagnostic assignment may be challenging. We studied blood or bone marrow from 270 patients with MDS, MDS/MPD, and CMPD for the presence of JAK2 V617F mutation using polymerase chain reaction, sequencing, and melting curve analysis.

The Philadelphia chromosome as a secondary abnormality in inv(3)(q21q26) acute myeloid leukemia at diagnosis: confirmation of p190 BCR-ABL mRNA by real-time quantitative polymerase chain reaction.

The Philadelphia chromosome (Ph) as a secondary cytogenetic abnormality is a rare event. It is observed mostly as an additional, late-appearing cytogenetic change during the evolution of acute leukemia and its presentation as a secondary change at the onset of disease is much rarer. We describe here a patient with acute myelogenous leukemia (AML) who had Ph as a secondary chromosome abnormality at diagnosis.

Frequencies and characterization of cytogenetically unrelated clones in various hematologic malignancies: seven years of experiences in a single institution.

Cytogenetically unrelated clones are uncommon findings in hematologic disorders. In the present study, among the 1,110 various hematologic malignancies analyzed during the past seven years, 27 (2.4%) patients had karyotypically unrelated clones: 3.

Efficient identification of T-cell clones associated with graft-versus-host disease in target tissue allows for subsequent detection in peripheral blood.

Graft-versus-host disease (GVHD) causes severe morbidity and mortality in allogeneic haematopoietic stem cell transplantation (HSCT) because of destruction of recipient tissues by donor alloreactive T cells. We hypothesized that GVHD-specific T-cell clones are expanded within affected tissue of HSCT patients and can also be detected in blood at the time of active disease. A multiplex polymerase chain reaction (PCR) was used to amplify T-cell receptor (TCR) variable beta (VB) chain rearrangements in skin biopsies from eight allogeneic HSCT patients.

Detection of mature T-cell leukemias by flow cytometry using anti-T-cell receptor V beta antibodies.

A broad array of antibodies directed against the variable (V) region of the T-cell receptor (TCR) beta (V beta) chain has become available in a directly conjugated multicolor format that permits assessment of 19 of 25 V beta families, covering 70% of the normal circulating T-cell repertoire. These antibodies were used to detect expanded T-cell populations in 43 peripheral blood samples submitted for suspected T-cell malignancy. Of 43 samples, 27 were diagnosed as follows: T-cell large granular lymphocyte leukemia, 14 samples; Sézary syndrome, 4 samples; T-cell prolymphocytic leukemia, 5 samples; or T-cell non-Hodgkin lymphoma or T-cell lymphoproliferative disorder not otherwise specified, 4 samples.

Spectral karyotyping in patients with acute myeloid leukemia and a complex karyotype shows hidden aberrations, including recurrent overrepresentation of 21q, 11q, and 22q.

We used spectral karyotyping (SKY) to study 29 adults with acute myeloid leukemia and a complex karyotype containing one to nine abnormalities that were not fully identifiable by G-banding. SKY showed the origin of rings and unidentified material in unbalanced translocations in all cases and the origin of markers in most, allowing reinterpretation of 136 aberrations and discovery of three aberrations hidden in normal chromosomes. SKY confirmed 10 and refined the interpretation of three balanced aberrations recognized by G-banding and identified another nine balanced aberrations, including a novel translocation involving the RUNX1 gene.