Biallelic variants in NUDCD2 associated with a multiple malformation syndrome with cholestasis and renal failure.

NudC-like protein 2 (NUDCD2) is a 4-exon protein-coding gene at 5q34. The protein appears to act in concert with other genes regulating cell migration and microtubule extension. Early studies in model organisms show associations with LIS1, HERC2, and cohesin subunits via a co-chaperone function with Heat shock protein 90 (Hsp90). It is a candidate gene for human pathology. We present two unrelated patients with biallelic variants in NUDCD2. Their phenotypes comprise similar dysmorphic facies, midline brain hypoplasia, hypothyroidism, pulmonary and aortic valve stenosis, severe dysfunction of the liver and kidneys, profound hypotonia, and early death. The cellular analysis demonstrates the absence of the NUDCD2 protein in fibroblasts of one patient with biallelic loss-of-function variants. The data suggest that NUDCD2 deficiency causes this recognizable syndrome that has features of a ciliopathy with additional complications.

Hemoglobin ß-Globin Variants In Hispanic Patients: An Institutional Experience From Dallas, Texas.

Hemoglobinopathies are the most common single-gene disorders in humans. There are 1,424 variants of human hemoglobin described with 951 involving the ß-globin gene. Ancestry and geography play a significant role in the incidence and nature of hemoglobinopathies, with African, Asian, and Mediterranean populations and their descendants being amongst the most affected. Investigation of variants in individuals of Hispanic descent is needed to reflect the changing demographics of the United States. Hemoglobin ß-globin evaluation through gel electrophoresis, high-performance liquid chromatography, and HBB gene sequencing was performed on patients from Texas hospitals between 2010 and 2015 and demographic parameters (age, sex, ethnicity) was subsequently analyzed. A total of 846 patients underwent hemoglobinopathy evaluation. A ß chain variant was detected in 628 of the 846 total patients. Hispanic patients represented 37% (314/846 patients), which were equally distributed between females (50%; 156/314) and males (50%; 156/314). A ß-globin chain variant was found in 67% of Hispanic patients with a distribution across 10 variants seen in greater than 1% of patients. For hemoglobin variants, an understanding of the regional and ethnic prevalence will improve patient care through more effective screening and identification of the variant, early diagnosis, and appropriate treatment if necessary, and better genetic counseling.

GAB1-ABL1 fusions in tumors that have histologic overlap with NTRK-rearranged spindle cell tumors.

Fibroblastic spindle cell tumors are a heterogeneous group of rare soft tissue tumors that are increasingly recognized as associated with a variety of kinase gene fusions. We report two cases of GAB1-ABL1 fusions in spindle cell tumors that histologically overlap with neurotrophic tyrosine receptor kinase (NTRK)-rearranged spindle cell tumors. The first case occurred in a 76-year-old female who had a large deep-seated spindle cell tumor composed of monotonous ovoid to spindle cells in a background of thick stromal collagen bands with prominent hyalinized vessels and inconspicuous mitoses (<1/10 HPF). Immunohistochemical stains showed co-expression of S100 and CD34. A GAB1-ABL1 fusion was detected by whole transcriptome RNA sequencing. The patient had a partial response to imatinib. The second case was previously described as a solitary fibrous tumor, occurring in a 9-year-old female with a cellular spindle cell tumor with patchy CD34 immunoexpression but no expression of S100. Upon clinicopathologic re-review, including anchored multiplex next-generation sequencing, a GAB1-ABL1 fusion was identified. In summary, we report the first two cases of spindle cell tumors with variable expression of CD34 and/or S100, driven by GAB1-ABL1 gene fusions with histologic overlap with NTRK-rearranged spindle cell tumors, suggesting that ABL-fusions may also be oncogenic drivers within this spectrum of tumors. These cases highlight the evolving understanding of fibroblastic spindle cell tumor biology and the utility of sequencing in identifying a targetable alteration.

Connecting the Dots From Fever of Unknown Origin to Myelodysplastic Syndrome: GATA2 Haploinsufficiency.

Leukemia-predisposing conditions, such as GATA2 haploinsufficiency, are known for their high penetrance and expressivity profiles. These disorders pose a difficult diagnostic challenge to even the most experienced clinician when they first present. We describe the case of a 17-year-old male presenting with features of nontuberculous mycobacterial infection, pulmonary fibrinoid granulomatous vasculitis, and myelodysplasia in the setting of a pathogenic GATA2 frameshift mutation confirmed by next-generation sequencing. The broad differential for GATA2 haploinsufficiency requires prompt recognition of key clinical features and laboratory abnormalities towards directing diagnosis and guiding appropriate and perhaps life-saving therapy.

Hb Alcorn County: A ß-Globin Variant [ß40(C6)Arg→Thr; HBB: c.122G>C (p.Arg41Thr)] with Increased Oxygen Affinity.

We describe Hb Alcorn County, a heterozygous hemoglobin (Hb) variant, in a 6-month-old Hispanic male and his mother. DNA sequencing demonstrated a mutation on the HBB gene [ß40(C6)Arg→Thr; HBB: c.122G>C (p.Arg41Thr)], predictive of a substitution of arginine to threonine at position 40 of the ß-globin protein. This amino acid substitution involves the α1ß2 contact and occurs at the same position as Hb Austin [ß40(C6)Arg→Ser; HBB: c.[123G>C or 123G>T] (p.Arg41Ser)] and Hb Athens-GA [ß40(C6)Arg→Lys; HBB: c.122G>A (p.Arg41Lys)], both of which show increased oxygen affinity.

An additional case of Hennekam lymphangiectasia-lymphedema syndrome caused by loss-of-function mutation in ADAMTS3.

Hennekam lymphangiectasia-lymphedema syndrome (HKLLS) is a genetically heterogeneous lymphatic dysplasia with characteristic of facial dysmorphism, neurocognitive impairments, and abnormalities of the pericardium, intestinal tract, and extremities. It is an autosomal recessive condition caused by biallelic mutations in CCBE1 (collagen- and calcium-binding epidermal growth factor domain-containing protein 1) (HKLLS1; OMIM 235510) or FAT4 (HKLLS2; OMIM 616006). CCBE1 acts via ADAMTS3 (a disintegrin and metalloprotease with thrombospondin motifs-3 protease) to enhance vascular endothelial growth factor C signaling. There is report of one family supporting mutations in ADAMTS3 as causative for the phenotype labeled as HKLLS3. Here, we report an additional case of HKLLS that appears to be associated with homozygous nonsense mutation of ADAMTS3.

Targeted MAPK Pathway Inhibitors in Patients With Disseminated Pilocytic Astrocytomas.

This report presents a series of 5 pediatric patients with disseminated pilocytic astrocytomas and frequent nonfusion activating mutations. Genetic variants in these patients' tumors include BRAF p.Val600Glu, BRAF p.Val600Asp, and KRAS p.Gly60_Gln62ins7. The 2 patients with BRAF-mutated tumors were treated with dabrafenib or a combination of dabrafenib plus trametinib. The patients had either near complete resolution of the primary tumor (BRAF p.Val600Glu) or a stable primary tumor (BRAF p.Val600Asp). Both patients showed improvement in leptomeningeal dissemination without significant toxicity. Genomic testing of disseminated pilocytic astrocytomas, particularly those arising at extracerebellar locations, may result in the identification of mutations associated with ERK/MAPK activation. Patients with these activating mutations may benefit from targeted therapies.

Application of a standardized screening protocol for diagnosis of invasive mold infections in children with hematologic malignancies.

PURPOSE: This study describes a standardized screening protocol for diagnosis of invasive mold infections in pediatric oncology patients with neutropenia and prolonged or recurrent fever. METHODS: A retrospective chart review was performed of children receiving intensive chemotherapy for hematologic malignancies who developed invasive mold infections from 2004 to 2011. Characteristics and outcomes were compared before and after implementation of the screening protocol in November 2006. The screen includes direct nasal endoscopy performed at the bedside by an otorhinolaryngologist, noncontrast computed tomography (CT) of the chest, and abdominal ultrasound in patients with neutropenia and prolonged or recurrent fever. RESULTS: Fifty patients had proven, probable, or possible invasive mold infections. Before routine use of direct nasal endoscopy, invasive nasosinal disease was detected in 5 of 19 patients (26 %) and all had a compatible clinical presentation. Thirteen of 31 patients (42 %) in the post-screen group had nasosinal disease, and fever was the only sign for 8 patients (62 %). Twenty-four patients with nasosinal disease had a sinus CT, and radiologic findings of bony erosion or peri-sinus invasion were never detected. Eight of 19 patients in the pre-screen group died from mold infection (42.1 %) versus 4 of 31 (12.9 %) in the post-screen group (p = 0.04). CONCLUSIONS: A screening protocol including direct nasal endoscopy, noncontrast chest CT, and abdominal ultrasound was effective in detecting invasive mold infections in at-risk patients. Nasosinal involvement often occurs before specific symptoms develop, and sinus CTs are insensitive and nonspecific. Bedside nasal endoscopy precludes radiation exposure associated with sinus CT and was associated with decrease in mold-related mortality, likely due to earlier diagnosis and initiation of appropriate antifungal therapy.

Characterization of the HBB: c.*233G > C Variant: No Evidence of a ß-Thalassemic Phenotype.

ß-Thalassemia (ß-thal) results from homozygous or compound heterozygous inheritance of ß-globin alleles that yield decreased or absent synthesis of the ß chain. Disease is frequently severe, requiring lifelong transfusion therapy. Heterozygosity for a ß-thal allele results in an asymptomatic carrier state with mild but characteristic hematological findings. More than 200 ß-globin alleles have been demonstrated to produce ß-thal. For populations with a high prevalence of ß-thal, screening for carrier status, genetic counseling and prenatal diagnosis are important components of efforts to both reduce disease incidence and provide early diagnosis and treatment. It is therefore important to define and characterize potential ß-thal alleles. We sought to further characterize the previously reported ß-thal allele, HBB: c.*233G > C. This variant is provisionally included in the HbVar database based on a study of Palestinians in the Gaza Strip with ß-thal disease or carrier status (known or suspected) where 4.2% of subjects were found to have HBB: c.*233G > C. In our patient population, we detected the HBB: c.*233G > C variant in 17.3% of individuals (17 heterozygotes, one homozygote) undergoing ß hemoglobin (Hb) gene sequencing at our laboratory over a 25-month period. Hematological parameters were analyzed to determine if these individuals demonstrated findings consistent with inheritance of a ß-thal allele. Individuals with the HBB: c.*233G > C variant did not demonstrate any abnormalities in hematological parameters characteristic of ß-thal carrier state (17 heterozygotes) or clinical evidence of disease (homozygote). Our data demonstrate no evidence for pathogenicity of the HBB: c.*233G > C variant but rather demonstrate that this variant is a common benign polymorphism.

Therapy-induced secondary acute myeloid leukemia with t(11;19)(q23;p13.1) in a pediatric patient with relapsed acute promyelocytic leukemia.

Acute myeloid leukemia is classified based upon recurrent cytogenetic abnormalities. The t(15;17)(q24.1;q21.1) abnormality is found in 5% to 8% of de novo acute myeloid leukemia and is diagnostic of acute promyelocytic leukemia (APL). The translocation results in fusion of the retinoic acid receptor-α (RARA) gene at 17q21.1 and the promyelocytic leukemia (PML) gene at 15q24.1. Standard APL therapy is a combination of all-trans retinoic acid and anthracycline-based chemotherapy. Anthracycline treatment is associated with secondary clonal chromosomal aberrations that can lead to therapy-related secondary myeloid neoplasms. We present a pediatric case of relapsed APL coexistent with treatment-associated secondary myeloid neoplasm with t(11;19)(q23;p13.1).

Leveraging faculty development to support validation of entrustable professional activities assessment tools in anatomic and clinical pathology training.

Entrustable professional activities (EPAs) are observable activities that define the practice of medicine and provide a framework of evaluation that has been incorporated into US medical school curricula in both undergraduate and graduate medical education. This manuscript describes the development of an entrustment scale and formative and summative evaluations for pathology EPAs, outlines a process for faculty development that was employed in a pilot study implementing two Anatomic Pathology and two Clinical Pathology EPAs in volunteer pathology residency programs, and provides initial validation data for the proposed pathology entrustment scales. Prior to implementation, faculty development was necessary to train faculty on the entrustment scale for each given activity. A "train the trainer" model used performance dimension training and frame of reference training to train key faculty at each institution. The session utilized vignettes to practice determination of entrustment ratings and development of feedback for trainees as to strengths and weaknesses in the performance of these activities. Validity of the entrustment scale is discussed using the Messick framework, based on concepts of content, response process, and internal structure. This model of entrustment scales, formative and summative assessments, and faculty development can be utilized for any pathology EPA and provides a roadmap for programs to design and implement EPA assessments into pathology residency training.

National pilot of entrustable professional activities in pathology residency training.

Entrustable professional activities (EPAs) are observable clinical skills and/or procedures that have been introduced into medical education at the student and resident levels in most specialties to determine readiness to advance into residency or independent practice, respectively. This publication describes the process and outcomes of a pilot study looking at the feasibility of using two anatomic pathology and two clinical pathology EPAs in pathology residency in 6 pathology residency programs that volunteered for the study. Faculty development on EPAs and their assessment was provided to pilot program faculty, and EPA assessment tools were developed and used by the pilot programs. Pre- and post-study surveys were given to participating residents, faculty, and program directors to gauge baseline practices and to gather feedback on the EPA implementation experience. Results demonstrated overall good feasibility in implementing EPAs. Faculty acceptance of EPAs varied and was less than that of program directors. Residents reported a significant increase in the frequency with which faculty provided formative assessments that included specific examples of performance and specific ways to improve, as well as increased frequency with which faculty provided summative assessments that included specific ways to improve. EPAs offered the most benefit in setting clear expectations for performance of each task, for providing more specific feedback to residents, and in increasing Program director's understanding of resident strengths abilities and weaknesses.

Leadership perspectives on osteopathic medical school applicants to pathology residency training.

The number of graduating allopathic (MD) medical students matching into pathology has declined in recent years, while the number of osteopathic (DO) medical students has increased modestly, given the rapid expansion of osteopathic medical schools. Nonscholarly publications and materials on the internet often perpetuate negative perceptions of osteopathic physicians. Anecdotally, perspectives exist that some pathology residency programs are not DO-friendly; however, the reasons and how widespread an effect this might be are unclear. Our survey queried pathology chairs and residency program directors about their perceptions of osteopathic applicants and their knowledge of osteopathic medical school/training in general. This study utilized two similar, parallel surveys of pathology chairs and residency program directors with general questions structured around the perceptions and knowledge of both allopathic and osteopathic physicians, their medical training, and the consideration of osteopathic applicants to pathology residency. Pathology residency leaders acknowledge some negative perceptions of osteopathic physicians in the medical profession, the news, and social media. They also have some knowledge and perception gaps regarding osteopathic training and applicants, although experience with training osteopathic physicians as residents has been equivalent to that with allopathic physicians, and consideration appears to be fairly equal for osteopathic applicants. Even though negative perceptions of osteopathic physicians persist in news and social media, our surveys demonstrate that the leadership of pathology residency programs does not hold the same degree of bias and that DOs perform well in allopathic pathology residency programs without evidence of inferior outcomes.

Myelodysplastic syndrome (MDS)-associated cytogenetic abnormalities in pediatric chronic myelogenous leukemia.

Chronic myelogenous leukemia (CML) is very rare in the pediatric population. We report the case of a 2-year-old female with CML and concurrent myelodysplastic syndrome (MDS) associated cytogenetic abnormalities. The co-existence of t(9;22) and chromosomal deletions that are associated with MDS poses a unique diagnostic challenge. Given the reported association of t(9;22) and genomic instability, we hypothesize that the chromosomal deletions represent clonal evolution of the CML.

Experiential exposure as the key to recruiting medical students into pathology.

Medical student interest and pursuit of a career in pathology have been steadily declining since 2015. We conducted three separate surveys of medical students to better understand these trends. In our first survey, we focused on assessing U.S. allopathic medical students understanding and perceptions of pathology. We later surveyed U.S. osteopathic medical students as a companion to the allopathic medical student survey, in which many similarities were discovered with some key differences. In our final survey, we specifically looked at curriculum differences between the U.S. allopathic medical schools that graduate the most students who enter pathology training programs (Group 1) versus those schools that graduate the fewest future pathologists (Group 2) to determine if the curriculum had an impact on medical student matriculation into pathology. Together, through these surveys, we were able to identify several remarkable recurring trends, presenting areas of targetable action. Here, we summarize themes from the three studies as well as a review of pertinent literature to offer best practices for exposing and engaging medical students to pathology and possibly recruiting students to consider pathology as a career.

How influential are medical school curriculum and other medical school characteristics in students' selecting pathology as a specialty?

There has been a significant decline in the number of United States allopathic medical students matching to pathology residency programs. Data acquired from the American Association of Medical Colleges (AAMC) show sustained variation in the medical school production of students who go on to pathology residency. When divided into groups based on the medical school's historical volume of graduates entering pathology, the schools in groups labeled Group 1 and Group 2 produced significantly higher and lower proportions of pathology residents, respectively. This study aimed to identify what medical school curriculum elements and other medical school characteristics might explain the differences observed in the AAMC data. The Dean or another undergraduate medical education contact from the Group 1 and Group 2 schools was invited to participate in an interview. Pathology Program Directors and Pathology Department Chairs were also included in communications. Thirty interviews were completed with equal numbers from each group. Interview questions probed pathology experiences, existence, and structure of a pathology interest group, options for post-sophomore fellowships, recent curriculum changes, and the extent of mentoring programs. Surprisingly, the curriculum does not appear to be a predictor of a medical school's production of students who enter pathology residency. A significantly greater percentage of Group 1 schools are public institutions compared to Group 2 schools. Other factors that may increase the number of students who go into pathology include mentoring, active learning versus observation, and post-sophomore fellowships or other opportunities to work in the capacity of a new pathology resident.

ETV6-NTRK3--Trk-ing the primary event in human secretory breast cancer.

In this issue of Cancer Cell, propose a single chromosomal translocation as the cause of a particularly troubling form of breast cancer, secretory carcinoma. They challenge widely held beliefs concerning breast carcinogenesis as well as beliefs concerning the absolute association of specific fusion genes with specific tumor types. Their data highlight the role of Trk signaling in breast cancer and also suggest a target for drug development.

A t(11;14)(q13;q32)/CCND1::IGH carrying progenitor germinal B-cell with subsequent cytogenetic aberrations contributes to the development of classic Hodgkin lymphoma.

Classic Hodgkin lymphoma (cHL) is characterized by the presence of Hodgkin Reed-Sternberg (HRS) cells. Although HRS cells express PAX5, cHL frequently lacks other B-cell markers. There is now evidence that HRS cells are monoclonal and are derived from germinal center B-cells. In terms of genetic aberrations, cHL frequently exhibit activated NF-kB signaling pathway. In this study, we present a case of cHL harboring a t(11;14) (q13;q32)/CCND1::IGH, identified by chromosome and fluorescence in situ hybridization analysis and with CCND1 expression in HRS cells. We also analyzed recurrent cytogenetic aberrations in t(11;14) positive mantle cell lymphoma (MCL) and those found in cHL from the literature to assess genetic overlap, clonal evolution, and to identify potential signaling pathways in cHL with CCND1::IGH. This analysis suggests the development of t(11;14)+ cHL and MCL from a transformed precursor cell with t(11;14) through genetic evolution and consequent deregulated pathways, including the NF-κB and NOTCH1 signaling.

The pathology fellowship application crisis: The current state and suggestions for remediation.

Problems within the Pathology fellowship application process in the US have been recognized and reported for years. Recently, members of the Graduate Medical Education Committee (GMEC) of the Association of Pathology Chairs (APC) and collaborators collected survey data from the residents themselves and the fellowship programs, as represented by both the fellowship program directors (members of the Fellowship Directors Ad Hoc Committee, FDAHC) and the program administrators (members of the Graduate Medical Education Administrators Section, GMEAS). These data are presented and discussed, and potential steps to resolve some of the problems around fellowship applications in pathology are presented.