Novel ELANE Mutation Associated with a Clinical Presentation of Cyclic Neutropenia.

OBJECTIVES: Congenital neutropenia, defined by absolute neutrophil count (ANC) 2.5x109/L in infants, includes a variety of genotypic alterations that manifest with chronic immunodeficiency and, as a result, presents in infancy with recurrent infections. The gene that encodes neutrophil elastase, ELANE, has pathological variants yielding two distinct phenotypes: severe congenital neutropenia (SCN) and cyclic neutropenia (CyN). While SCN exhibits persistent pathologic ANC values, CyN exhibits pathologic ANC values in a patterned fashion which can recur in 21-day intervals. Here, we describe a patient with a novel heterozygous ELANE deletion (c.224+(4_19)del16) presenting with clinical features consistent with CyN and a response to first-line therapy of granulocyte colony- stimulating factor.

What's in a Name? The Many Classifications of Acute Myeloid Leukemia with Dysplasia.

OBJECTIVES: Acute myeloid leukemia with myelodysplasia-related changes (AML-MRC) is a high-risk subtype of AML that has recently undergone significant reclassification. Proper classification requires the integration of clinical history and diagnostic studies including peripheral blood and bone marrow morphology, flow cytometry, cytogenetic and molecular studies. The latter have significant clinical and prognostic implications. We present a case of a 55-year-old male diagnosed with AML-MRC with a pathogenic variant in TP53 and amplification of KMT2A (MLL) without rearrangement. We discuss presentation, importance of diagnostic testing through multiple modalities, and the changes in classification and diagnostic criteria between the 2017 World Health Organization (WHO) revised 4th edition and the WHO 5th edition and International Consensus Classification (ICC).

Pediatric Myelodysplastic Syndrome with SF3B1 Mutation.

OBJECTIVES: Patients with Fanconi Anemia (FA) have an increased risk of developing myeloid malignancies, which often precede the diagnosis of FA. We describe a patient with non-specific clinical findings diagnosed with myelodysplastic syndrome (MDS) at 17 years of age. A pathogenic SF3B1 alteration was identified and prompted evaluation for a bone marrow failure syndrome. Chromosomal breakage testing demonstrated an increase in breakage and radial formation; a targeted FA molecular panel identified variants of unknown significance in FANCB and FANCM. To date, reports of pediatric patients, with or without a co-morbid diagnosis of FA, diagnosed with MDS with SF3B1 alteration are rare. We describe a patient with FA diagnosed with MDS with ring sideroblasts and multilineage dysplasia (MDS-RS-MLD, WHO revised 4th edition) with an associated SF3B1 alteration and discuss the new classifications of this entity. In addition, as the knowledge around FA grows, so too does the knowledge about genes associated with FA. We present a novel variant of unknown significance in FANCB, to add to the growing body of literature about genetic alterations identified in individuals with a clinical picture most in keeping with FA.

Myelodysplastic Syndrome with Excess Blasts 2 (MDS-EB-2): A Historical Overview and Review of Forthcoming Classifications.

OBJECTIVES: Myelodysplastic syndrome with excess blasts-2 (MDS-EB-2) primarily affects adults older than 50 years and confers a worse prognosis with a higher risk of transformation to acute myeloid leukemia (AML) compared to myelodysplastic syndrome (MDS) and MDS with excess blasts-1 (MDS-EB-1). In ordering diagnostic studies for MDS, cytogenetic and genomic studies are vital as they have significant clinical and prognostic implications for the patient. We present a case of a 71-year-old male diagnosed with MDS-EB-2 with a pathogenic loss-of-function TP53 variant and discuss presentation, pathogenesis, and the importance of thorough diagnostic testing through multiple modalities to accurately diagnose and subtype MDS. In addition, we explore a historical overview of the diagnostic criteria of MDS-EB-2 and how it has changed over time from the World Health Organization (WHO) 4th edition in 2008, the WHO revised 4th edition in 2017, and the upcoming WHO 5th edition and International Consensus Classification (ICC) for 2022.

Acute Myeloid Leukemia with Myelodysplasia-Related Changes Presenting as Vitamin B12 Deficiency: A Cautionary Tale.

OBJECTIVES: Acute myeloid leukemia may present with significant dysmyelopoiesis within the peripheral blood smear and bone marrow aspirate. In the setting of Vitamin B12 deficiency, proliferation of a clonal population of malignant cells can become impaired, masking an underlying myelodysplastic or leukemic process. Typically, the cautionary tale warns against diagnosing acute myeloid leukemia before ruling out Vitamin B12 deficiency. Here we describe a patient who initially presented with pancytopenia and Vitamin B12 deficiency who, upon supplementation, developed overt acute myeloid leukemia. This case will highlight the importance of cytogenetic and molecular studies as essential diagnostic tools in patients with unique presentations.

BCR-ABL1-like B-lymphoblastic leukemia/lymphoma: Review of the entity and detection methodologies.

BCR-ABL1-like B-lymphoblastic leukemia/lymphoma (BCR-ABL1-like ALL or Ph-like ALL) is a neoplastic proliferation of lymphoblasts that has a gene expression profile similar to that of B-ALL with t(9;22)(q34.1;q11.2) BCR-ABL1, but lacks that gene fusion. It is associated with poor prognosis and is seen in 10%-20% of pediatric cases and 20%-30% of adult cases of ALL. It is included as a provisional entity in the revised 4th edition of the WHO Classification. A variety of different genetic abnormalities are identified in this entity, but they all converge on pathways that are potentially responsive to the addition of targeted therapy to conventional chemotherapy. Thus, it is important to screen for BCR-ABL1-like ALL, particularly in adults and pediatric patients with high-risk clinical features. Here, we provide a brief overview of the genetic profile and clinical features of BCR-ABL1-like ALL and review laboratory methodologies for routine identification of this genetically heterogeneous entity.

Clinicopathologic Features and Clinical Outcome Differences in De Novo Versus Secondary Histiocytic Sarcomas: A Multi-institutional Experience and Review of the Literature.

INTRODUCTION: Histiocytic sarcoma (HS) is a rare malignant neoplasm that can occur in patients with a history of treatment for hematologic or solid tumors. Because no optimal treatment has been defined and standardized, the treatment modalities used and outcomes reported have been highly variable. In the present study, 3 major institutions explored the clinicopathologic features of de novo and secondary HS. MATERIALS AND METHODS: After institutional review board approval, clinical, histopathologic, and immunophenotypic data were collected from patients with a diagnosis of HS and treated at the University of Alabama at Birmingham, University of New Mexico, or Brooke Army Medical Center from January 1, 2003 to December 31, 2016. RESULTS: The databases revealed 23 unique cases of HS. The mean age was 55.4 years (range, 5-84 years) and the male-to-female ratio was 0.92. The mean follow-up period was 89.82 months (range, 14-172 months). Of the 23 patients with HS, 6 had a history of an unrelated malignancy treated with chemotherapy or radiotherapy, with a mean delay of 42.2 months (range, 12-91 months). The mean overall survival during the study period was 54.1 months. The overall survival of those with de novo HS was 70 months compared with 11.8 months for those with secondary HS, with a mean difference of 58.2 months (95% confidence interval, 26.2-90.2 months; P = .001). CONCLUSION: The shorter overall survival with secondary HS suggests a more aggressive course than that with de novo disease. Larger scale studies are needed to further investigate the biology and genetics of HS.

Lyme Disease Testing in a High-Incidence State: Clinician Knowledge and Patterns.

OBJECTIVES: Lyme disease (LD) incidence is increasing, but data suggest some clinicians are not fully aware of recommended procedures for ordering and interpreting diagnostic tests. The study objective was to assess clinicians' knowledge and practices regarding LD testing in a high-incidence region. METHODS: We distributed surveys to 1,142 clinicians in the University of Vermont Medical Center region, of which 144 were completed (12.6% response rate). We also examined LD laboratory test results and logs of calls to laboratory customer service over a period of 2.5 years and 6 months, respectively. RESULTS: Most clinicians demonstrated basic knowledge of diagnostic protocols, but many misinterpreted Western blot results. For example, 42.4% incorrectly interpreted a positive immunoglobulin M result as an overall positive test in a patient with longstanding symptoms. Many also reported receiving patient requests for unvalidated tests. CONCLUSIONS: Additional education and modifications to LD test ordering and reporting systems would likely reduce errors and improve patient care.

Transient monoclonal gammopathy induced by Candida fungemia.

A 41-year-old woman was admitted for Candida fungemia. On hospital day 4, a routine complete blood count and peripheral smear showed circulating plasma cells. Initial workup showed an M-component on serum protein electrophoresis with 6% λ-predominate plasma cells by flow cytometry. The patient was treated with intravenous antifungal therapy. Her 6-month follow-up laboratory evaluation revealed resolution of the M-component and only rare polyclonal plasma cells in peripheral blood by flow cytometry. This case illustrates that transient monoclonal gammopathy can be induced by fungal infection. It is important to exclude a plasma cell neoplasm or a B-cell lymphoma and to follow the patient until resolution of abnormal findings.

Transition to Subspecialty Sign-Out at an Academic Institution and Its Advantages.

Many pathology departments are introducing subspecialty sign-out in surgical pathology. In 2014, the University of Vermont Medical Center transitioned from general sign-out to partial subspecialty sign-out to include gastrointestinal and breast/cervix subspecialty benches; other specimens remained on general benches. Our experiences with the transition are described, including attending pathologist, trainee, support staff, and clinician satisfaction. A survey was e-mailed to all University of Vermont Medical Center anatomic pathology attendings, pathology trainees, pathologist assistants and grossing technicians, and clinicians who send surgical pathology specimens, immediately before and 1 year after transitioning to partial subspecialty sign-out. Quality assurance metrics were obtained for the 18 months prior to and following the transition. Gastrointestinal and breast/cervix attendings were more satisfied with partial subspecialty sign-out compared to those on the general benches. Overall, trainees were more satisfied with general sign-out because of the rotation schedule but preferred partial subspecialty sign-out due to improved teaching and more focused learning while on subspecialty benches. Clinicians remained very satisfied with our department and our reports; no differences were observed. Turnaround time was unchanged. After switching to partial subspecialty sign-out, there were significantly fewer discrepancies following multidisciplinary conference review for gastrointestinal and breast/cervix cases but remained the same for general cases. Fewer formal internal consults were performed after transitioning to partial subspecialty sign-out across all areas, but more notable for gastrointestinal and breast/cervix cases. Our data show improved quality assurance metrics and trainee education in a subspecialty sign-out setting compared to general sign-out setting.

Fetal Tissue Procurement for Karyotype Analysis: Clinician or Pathologist - Which is Better?

UNLABELLED: Chromosomal abnormalities are detected in up to 13% of stillbirths and over 20% of those with developmental anomalies. These estimates may be low since up to 50% of samples fail to achieve a result due to microbial overgrowth or nonviability. Tissue for cytogenetics can be procured at bedside by the clinician or by the pathologist in the laboratory. With clinical collection, tissue is placed into culture media immediately, increasing chances of growth. However, collection competes for attention with other activities, which may result in microbial overgrowth or selection of maternal rather than fetal tissue. Laboratory procurement occurs in a controlled environment using sterile technique, but delay in collection may decrease viability. Our goal was to determine which collection method yields better results. METHODS: We reviewed cases from 2007-2013 that had two samples submitted for cytogenetics, one from the clinician and one from the pathologist. Specimen source, delivery, collection, and culture setup times, harvest date, cell growth, microbial overgrowth, maternal contamination and final result were obtained from medical records and cytogenetic culture sheets. FINDINGS: There was no difference in growth rate, maternal cell contamination, or reporting time between clinician- and pathologist-procured samples despite delay in collection time for laboratory samples. Clinical samples had more microbial overgrowth. Compared to samples collected at bedside, samples collected in the laboratory had a lower rate of microbial contamination with similar growth and maternal cell contamination rates, despite prolonged time to collection. Collecting samples both at bedside and in the laboratory is unnecessary.

Sarcomatoid renal cell carcinoma is an example of epithelial--mesenchymal transition.

BACKGROUND: Sarcomatoid renal cell carcinomas (SRCC) are composed of two cell populations, a sarcomatous component (SC) and a carcinomatous component (CC). SRCC are particularly aggressive and often present at an advanced stage at diagnosis. Epithelial-mesenchymal transition (EMT) has been proposed as a mechanism for the development of SC from CC. AIMS AND METHODS: E- to N-cadherin switching, localisation of ß-catenin, and expression of Snail and secreted protein acidic and rich in cysteine (SPARC) (markers of EMT) were studied to determine whether SRCC is an example of EMT. Expression of these markers was analysed by immunohistochemistry on 21 cases of SRCC that had both SC and CC and scored according to intensity and extent. RESULTS: E-cadherin expression was decreased in SC (Wilcoxon signed-rank test, p=0.0004) while N-cadherin expression was high in both components (p=0.46). Membranous ß-catenin expression was decreased in SC (p<0.0001) while cytoplasmic expression was increased (p=0.0002). Snail and SPARC had higher expression in SC (p=0.002 and p<0.0001, respectively). When the scores were dichotomised into low and high expression levels, the results using McNemar's test substantiated the above results. CONCLUSIONS: E- to N-cadherin switching, dissociation of ß-catenin from the membrane, and increased expression of Snail and SPARC in SC indicate that SRCC is an example of EMT. High expression of N-cadherin and Snail in CC suggest early involvement in initiating EMT. Once EMT is established, loss of E-cadherin, release of ß-catenin into the cytoplasm, and expression of SPARC correspond with mesenchymal phenotypic expression.