Lymphomas and Amyloid in the Gastrointestinal Tract.

Lymphoproliferative disorders are a heterogeneous group of neoplasms with varying clinical, morphologic, immunophenotypic, and genetic characteristics. A subset of lymphomas have a proclivity for the gastrointestinal tract, although this region may also be involved by systemic lymphomas. In addition, a number of indolent lymphoproliferative disorders of the gastrointestinal tract have been defined over the past decade, and it is important to accurately differentiate these neoplasms to ensure that patients receive the proper management. Here, the authors review lymphoid neoplasms that show frequent gastrointestinal involvement and provide updates from the recent hematolymphoid neoplasm classification systems.

Co-occurring mutations in ASXL1, SRSF2, and SETBP1 define a subset of myelodysplastic/ myeloproliferative neoplasm with neutrophilia.

Identification of genomic signatures with consistent clinicopathological features in myelodysplastic/myeloproliferative neoplasm (MDS/MPN) is critical for improved diagnosis, elucidation of biology, inclusion in clinical trials, and development of therapies. We describe clinical and pathological features with co-existence of mutations in ASXL1 (missense or nonsense), SRSF2, and SKI homologous region of SETBP1, in 18 patients. Median age was 68 years with a male predominance (83%). Leukocytosis and neutrophilia were common at presentation. Marrow features included hypercellularity, granulocytic hyperplasia with megakaryocytic atypia, while the majority had myeloid hyperplasia and/or erythroid hypoplasia, myeloid dysplasia, and aberrant CD7 expression on blasts. Mutations in growth signaling pathways (RAS or JAK2) were noted at diagnosis or acquired during the disease course in 83% of patients. Two patients progressed upon acquisition of FLT3-TKD (acute myeloid leukemia) or KIT (aggressive systemic mastocytosis) mutations. The prognosis is poor with only two long-term survivors, thus far, who underwent blood or marrow transplantation. We propose that the presence of co-occurring ASXL1, SRSF2, and SETBP1 mutations can be diagnostic of a subtype of MDS/MPN with neutrophilia if clinical and morphological findings align. Our report underscores the association between genotype and phenotype within MDS/MPN and that genomic signatures should guide categorization of these entities.

Pathology Residency Program Special Expertise Tracks Meet the Needs of an Evolving Field.

Pathologists who enter the workforce must have a diverse skill set beyond that of clinical diagnostics alone. Anticipating this need, the Johns Hopkins Pathology Residency Program developed Special Expertise Tracks to enhance training in relevant subspecialty domains. Using a combination of discussions and surveys, we assessed: (1) our current resident curriculum; (2) perceived curricular strengths and needs; (3) resident career preferences and ultimate career paths; (4) perceived barriers to implementing an advanced elective curriculum; and (5) available departmental/institutional resources. Additionally, we utilized the Accreditation Council for Graduate Medical Education Pathology Milestones as a curricular guide. Six professional residency training Special Expertise Tracks were established: Education, Physician-Scientist Research, Informatics, Quality Improvement/Quality Assurance/Value-Based Care, Health Policy/Hospital Management and Global Health. After implementation in 2017, the Education track has had 4 residents complete the curriculum successfully; the Physician-Scientist Research track has had 2 residents and the Informatics and Global Health tracks have each had one resident successfully complete their respective curricula. Currently, 5 residents are pursuing the Education track, one is pursuing the Physician-Scientist Research track, one is pursuing the Informatics track, and 2 residents are pursuing the Global Health track. Five residents have completed long-term projects including developing several e-learning modules, an online free digital cytopathology atlas, peer-reviewed articles, book chapters, and books. The Johns Hopkins Pathology Resident Special Expertise Track program provides pathology residents an opportunity to gain meaningful experience and additional skills tailored to their individual career interests.

Molecular Pathology of Mature Lymphoid Malignancies.

Lymphoid malignancies are a broad and heterogeneous group of neoplasms. In the past decade, the genetic landscape of these tumors has been explored and cataloged in fine detail offering a glimpse into the mechanisms of lymphomagenesis and new opportunities to translate these findings into patient management. A myriad of studies have demonstrated both distinctive and overlapping molecular and chromosomal abnormalities that have influenced the diagnosis and classification of lymphoma, disease prognosis, and treatment selection.

Strategies to Enhance Diversity, Equity, and Inclusion in Pathology Training Programs: A Comprehensive Review of the Literature.

CONTEXT.­: Like many medical specialties, pathology faces the ongoing challenge of effectively enriching diversity, equity, and inclusion within training programs and the field as a whole. This issue is furthered by a decline in US medical student interest in the field of pathology, possibly attributable to increasingly limited pathology exposure during medical school and medical student perceptions about careers in pathology. OBJECTIVE.­: To review the literature to identify the challenges to diversity, equity, and inclusion in pathology, with an emphasis on the pathology trainee pipeline. To evaluate the medical education literature from other medical specialties for diversity and inclusion-focused studies and initiatives, and determine the outcomes and/or approaches relevant for pathology training programs. DATA SOURCES.­: A literature review was completed by a search of the PubMed database, as well as a similar general Google search. Additional resources, including the Web sites of the Association of American Medical Colleges, the Electronic Residency Application Service, and the National Resident Matching Program, were used. CONCLUSIONS.­: Many strategies exist to increase diversity and encourage an inclusive and equitable training environment, and many of these strategies may be applied to the field of pathology. Interventions such as increasing exposure to the field, using a holistic application review process, and addressing implicit biases have been shown to promote diversity, equity, and inclusion in many medical specialties. In addition, increasing access to elective and pipeline programs may help to bolster medical student interest in careers in pathology.

Continuing Undergraduate Pathology Medical Education in the Coronavirus Disease 2019 (COVID-19) Global Pandemic: The Johns Hopkins Virtual Surgical Pathology Clinical Elective.

CONTEXT.­: In the early months of the response to the coronavirus disease 2019 (COVID-19) pandemic, the Johns Hopkins University School of Medicine (JHUSOM) (Baltimore, Maryland) leadership reached out to faculty to develop and implement virtual clinical clerkships after all in-person medical student clinical experiences were suspended. OBJECTIVE.­: To develop and implement a digital slide-based virtual surgical pathology (VSP) clinical elective to meet the demand for meaningful and robust virtual clinical electives in response to the temporary suspension of in-person clinical rotations at JHUSOM. DESIGN.­: The VSP elective was modeled after the in-person surgical pathology elective to include virtual previewing and sign-out with standardized cases supplemented by synchronous and asynchronous pathology educational content. RESULTS.­: Validation of existing Web communications technology and slide-scanning systems was performed by feasibility testing. Curriculum development included drafting of course objectives and syllabus, Blackboard course site design, electronic-lecture creation, communications with JHUSOM leadership, scheduling, and slide curation. Subjectively, the weekly schedule averaged 35 to 40 hours of asynchronous, synchronous, and independent content, approximately 10 to 11 hours of which were synchronous. As of February 2021, VSP has hosted 35 JHUSOM and 8 non-JHUSOM students, who have provided positive subjective and objective course feedback. CONCLUSIONS.­: The Johns Hopkins VSP elective provided meaningful clinical experience to 43 students in a time of immense online education need. Added benefits of implementing VSP included increased medical student exposure to pathology as a medical specialty and demonstration of how digital slides have the potential to improve standardization of the pathology clerkship curriculum.

Myeloid Neoplasm with PDGFRA Rearrangement Manifesting as a Retromolar Pad Mass.

Myeloid neoplasms with PDGFRA rearrangement are rare, and most commonly present with features of chronic eosinophilic leukemia; however, they rarely manifest as acute myeloid or lymphoblastic leukemia. Patients typically present with symptoms of hypereosinophilia including cardiovascular and pulmonary symptoms. An increase in mast cells is also a common feature of this disease, and there may be elevated serum tryptase with significant clinical overlap with systemic mastocytosis. Here, we present an unusual case of a myeloid neoplasm with PDGFRA rearrangement manifesting as a retromolar pad mass in a patient with a prior diagnosis of systemic mastocytosis. This case highlights the possibility of soft tissue involvement by myeloid neoplasms with PDGFRA rearrangement in the oral cavity. The identification of this entity is of significant clinical importance because many patients can be effectively treated with tyrosine kinase inhibitors.

Current and Historical Trends in Diversity by Race, Ethnicity, and Sex Within the US Pathology Physician Workforce.

OBJECTIVES: This study assessed historical and current gender, racial, and ethnic diversity trends within US pathology graduate medical education (GME) and the pathologist workforce. METHODS: Data from online, publicly available sources were assessed for significant differences in racial, ethnic, and sex distribution in pathology trainees, as well as pathologists in practice or on faculty, separately compared with the US population and then each other using binomial tests. RESULTS: Since 1995, female pathology resident representation has been increasing at a rate of 0.45% per year (95% confidence interval [CI], 0.29-0.61; P < .01), with pathology now having significantly more females (49.8%) compared to the total GME pool (45.4%; P < .0001). In contrast, there was no significant trend in the rate of change per year in black or American Indian, Alaskan Native, Native Hawaiian, and Pacific Islander (AI/AN/NH/PI) resident representation (P = .04 and .02). Since 1995, underrepresented minority (URM) faculty representation has increased by 0.03% per year (95% CI, 0.024-0.036; P < .01), with 7.6% URM faculty in 2018 (5.2% Hispanic, 2.2% black, 0.2% AI/AN/NH/PI). CONCLUSIONS: This assessment of pathology trainee and physician workforce diversity highlights significant improvements in achieving trainee gender parity. However, there are persistent disparities in URM representation, with significant underrepresentation of URM pathologists compared with residents.

The "Race" Toward Diversity, Inclusion, and Equity in Pathology: The Johns Hopkins Experience.

With 3.8% black trainees in 2012, pathology had significantly fewer trainees from groups underrepresented in medicine compared to other specialties. To address this, faculty in the Johns Hopkins Department of Pathology established an outreach program and funded rotation for students underrepresented in medicine and from disadvantaged groups. The aims were to increase exposure to the field and improve diversity, inclusion, and equity in pathology. A 1-month rotation for students underrepresented in medicine was established in 2013. Rotation schedules tailored to each rotator's interests included resident conferences and individual faculty meetings. In 2016, a proactive outreach program was established. Faculty visited historically black medical schools and underrepresented in medicine student groups at other institutions, where they gave a "Careers in Pathology" presentation targeted to second- and third-year medical students. Faculty also attended underrepresented in medicine student conferences and participated in high school student programs to further expand the underrepresented in medicine pipeline into medicine and pathology. Since 2016, fourteen outreach presentations have been delivered. The number of rotators increased from 1 in 2013 to 18 in July 2019. Rotators self-identified as African, African American, Hispanic, and Native American. Most were second- to fourth-year medical students, and 1 was a pathology resident. Six rotators are currently pathology residents, and others are strongly considering applying to pathology. The outreach efforts account for the success of our rotation, which, in turn, has had a positive impact on interest in pathology. However, we recognize barriers to retention and intend to incorporate additional professional development activities to further address equity.

Accuracy and clinical implications of pre-operative breast core needle biopsy diagnoses of fibroepithelial neoplasms and sarcomatoid carcinomas.

PURPOSE: Accurate classification of breast phyllodes tumors (PTs) on core biopsy can be challenging. The differential diagnosis of benign PT (BP) is fibroadenoma (FA), whereas the differential diagnosis of malignant PT (MP) is sarcomatoid (metaplastic) carcinoma (SC). METHODS: Here, we compare the pre-excision core biopsy diagnosis and clinicopathologic features of histologically confirmed MP, borderline PT (BLP), BP, FA, and SC. Consecutive cases of 34 histologically confirmed PT (14 MP, 10 BLP, 10 BP), 13 SC, and 10 FA were identified. RESULTS: A core biopsy diagnosis of SC was made only in SC (77%, p = 0.003). The diagnosis "malignant neoplasm" or "atypical spindle cell neoplasm" was made in 100% MP and 23% SC, but no other tumor (p = 0.0001). The diagnosis "phyllodes tumor" was made only in PT (44% BLP, 11% BP, p = 0.06). The diagnosis "fibroepithelial lesion" was made in 44% BLP, 67% BP, and 29% FA. The diagnosis "FA" was made most commonly in FA (57%) (versus 22% BP and no other tumor; p = 0.002). Neoadjuvant therapy was given only in SC (23%, p = 0.03); adjuvant therapy was given in 46% SC and 13% MP (p = 0.04). CONCLUSIONS: A pre-operative core biopsy diagnosis of "malignant spindle cell neoplasm" separates MP and SC from BLP, BP, and FA. However, MP and SC can have overlapping features on core biopsy. Thus, one must be careful not to overcall SC on core biopsy, as patients diagnosed with SC may receive neoadjuvant therapy. A core biopsy diagnosis of "phyllodes tumor" is specific for PT and can guide treatment planning of a wide local excision.

Differential Vascularity in Genetic and Nonhereditary Heterotopic Ossification.

Introduction. Nonhereditary heterotopic ossification (NHO) is a common complication of trauma. Progressive osseous heteroplasia (POH) and fibrodysplasia ossificans progressiva (FOP) are rare genetic causes of heterotopic bone. In this article, we detail the vascular patterning associated with genetic versus NHO. Methods. Vascular histomorphometric analysis was performed on patient samples from POH, FOP, and NHO. Endpoints for analysis included blood vessel (BV) number, area, density, size, and wall thickness. Results. Results demonstrated conserved temporal dynamic changes in vascularity across all heterotopic ossification lesions. Immature areas had the highest BV number, while the more mature foci had the highest BV area. Most vascular parameters were significantly increased in genetic as compared with NHO. Discussion. In sum, both genetic and NHO show temporospatial variation in vascularity. These findings suggest that angiogenic pathways are potential therapeutic targets in both genetic and nonhereditary forms of heterotopic ossification.

B-Lymphoid Blast Phase of Chronic Myeloid Leukemia: A Case Report and Review of the Literature.

Chronic myeloid leukemia (CML) is a clonal hematopoietic stem cell disorder characterized by a reciprocal translocation, t(9;22) (q34.1;q11.2). This leads to fusion of the BCR and ABL1 genes, encoding an active tyrosine kinase that causes unregulated proliferation of the myeloid lineage. The BCR/ABL1 fusion protein is found not only in CML, but also in a subset of de novo B-lymphoblastic leukemia (B-LL). However, the fusion protein in CML is characteristically the slightly longer p210 variant, whereas the p190 variant is more frequently found in B-LL. Without treatment, CML will progress to accelerated and/or blast phase (BP). Disease progression is often characterized by accumulation of additional chromosomal abnormalities. The development of tyrosine kinase inhibitor (TKI) therapy that targets BCR/ABL1 has revolutionized treatment of CML and vastly improved outcomes, although the disease can still progress despite TKI therapy. Blast phase most commonly manifests as myeloid BP; however, up to 30% of BP presents as lymphoid BP (LBP), typically of the B-cell lineage. The B-lymphoblasts of LBP have a phenotype indistinguishable from that of de novo B-LL. However, LBP typically carries the p210 BCR/ABL transcript and may show distinct chromosomal anomalies, including loss of chromosome 9p. The prognosis for CML-BP is poor, although survival has improved with TKI therapy and stem cell transplant, and LBP has been associated with superior survival compared with myeloid BP. Here we present a case of CML in B-lymphoid BP and review the current literature.

Chondromyxoid Fibroma of the Pelvis: Institutional Case Series With a Focus on Distinctive Features.

Chondromyxoid fibroma (CMF) is a relatively uncommon benign bone tumor of cartilaginous differentiation. The primary pitfall in the histopathologic diagnosis of CMF is confusion with a high-grade chondrosarcoma, owing to the atypical stellate and spindled cells set within a chondromyxoid background. CMF is particularly challenging to diagnose within the pelvis, where clinical suspicion for chondrosarcoma is high and benign lesions may grow to a large size to occupy the pelvic bones. In our practice, we noted this difficulty in several consecutive cases, especially when older patients presented with CMF within the pelvis. This prompted an institutional retrospective case review of all CMF within the pelvis. In 10 cases, we found overall that CMF of pelvis occurred in an older age range (mean age = 48.6 years), was larger in size (mean size = 6.0 cm), and showed a higher rate of soft tissue extension (50%) as compared with prior reports of nonpelvic CMF. Typical histologic features of CMF were seen in all cases; however, a high frequency of dystrophic calcification (50%) and necrosis (30%) was observed. Of interest, these aggregate demographic, radiologic, and histologic findings are all consistent with a benign neoplasm that has grown undetected within the pelvis over a long period of time. Recognition of these differences between pelvic CMF and tumors involving other sites will aid in avoiding misdiagnosis of this uncommon entity.