Epidemiology and Pathology of T- and NK-Cell Lymphomas.

PURPOSE: This review will describe and update readers on the recent changes in the 2017 WHO classification regarding peripheral T-cell lymphomas. RECENT FINDINGS: Signficant advances in molecular studies have resulted in revisions to the classification as well as introduction to provisional entities such as breast implant-associated ALCL and nodal PTCL with T-follicular helper phenotype. SUMMARY: Major advances in molecular and gene expression profiling has expanded our knowledge of these rare and aggressive diseases.

Bone Marrow Collection: Comparison of Unassisted vs Assisted Bedside Collections by a Laboratory Technologist.

OBJECTIVES: Bone marrow collections are often difficult, and creating quality smears and touch preparations at the bedside can prove challenging. The objective of this study is to compare the quality of bone marrow specimens between unassisted and assisted bone marrow collections by a bone marrow technologist. METHODS: Data for this study were collected from 422 hematopathology reports over 14 months. We recorded the bone marrow quality of the different parts (aspirate smears, touch imprints, core biopsy, and clot/particle sections) as adequate, suboptimal, or inadequate. Student t test statistical analysis was performed between the corresponding parts in the two groups. RESULTS: Our results demonstrate that the quality of assisted bone marrow specimens is significantly better compared with unassisted specimens, particularly for the aspirate smears (P < .0001) and touch imprints (P < .0001). Notably, the quality of aspirate smears was improved, which is important for cytologic evaluation. CONCLUSIONS: We conclude that assistance by a bone marrow technologist resulted in a significant improvement in the quality of bone marrow collection.

Novel t(1;8)(p31.3;q21.3) NFIA-RUNX1T1 Translocation in an Infant Erythroblastic Sarcoma.

OBJECTIVES: Pure erythroid leukemia (PEL) is exceptionally rare in the pediatric setting. Four pediatric PEL cases with t(1;16)(p31;q24) NFIA-CBFA2T3 were reported previously. We present a case of an infant with PEL presenting with erythroblastic sarcoma and harboring a novel t(1;8)(p31.3;q21.3) NFIA-RUNX1T1 fusion detected by RNA sequencing and conventional karyotype. METHODS: Bone marrow (BM) and abdominal mass biopsies from the patient were evaluated with extensive immunohistochemical, flow cytometric, cytogenetic, and molecular studies. RESULTS: The patient was a female infant who presented between 2 and 5 months of age with cytopenias and an enlarging abdominal mass. Blasts in the BM and abdominal mass expressed CD71 and CD117 with focal expression of CD43, E-cadherin, epithelial membrane antigen, and hemoglobin A. They were negative for additional myeloid, lymphoid, and nonhematolymphoid markers. These findings were most consistent with PEL and erythroblastic sarcoma. RNA sequencing revealed the novel NFIA-RUNX1T1 fusion. CONCLUSIONS: Along with the previously reported PELs with NFIA-CBFA2T3 fusions, we describe a subset of PELs that occur in children, that frequently display extramedullary disease, and that harbor rearrangements of NFIA with core binding factor genes. We hypothesize that, together, these cases represent a rare but distinct clinicopathologic group of pediatric PELs with recurrent genetic abnormality.

Updates of Peripheral T Cell Lymphomas Based on the 2017 WHO Classification.

PURPOSE OF REVIEW: This review will describe and update the readers on the recent changes of the 2017 WHO classification in regard to peripheral T cell lymphomas. RECENT FINDINGS: Significant advances in molecular studies have resulted in revisions of the classification as well as introduction of provisional entities (such as breast implant-associated ALCL, nodal PTCL with TFH phenotype). Major advances in molecular and gene expression profiling have expanded our knowledge of T cell lymphomas, including updates in the diagnostic criteria and sub-classification which will facilitate in improving patient care and research.

Pulmonary infantile hemangioma presenting as a mass in a premature male infant: a case report focusing on pathological features.

Infantile hemangiomas are the most common benign neoplasm of infancy, with most occurring in the head and neck region. Predisposing factors include prematurity, low birth weight, multiple gestations, advanced maternal age, and chorionic villous sampling. In addition, white women, particularly those with a family history, are also at a higher risk. However, pulmonary infantile hemangiomas are exceedingly rare, with only a few case reports in the literature. Infantile hemangiomas should be considered in the differential diagnosis of a pulmonary mass in the early pediatric population. We present a case of pulmonary infantile hemangioma in a premature male infant successfully managed by surgical excision, with an emphasis on the pathogenesis and histologic features.

Renal Collision and Composite Tumors: Imaging and Pathophysiology.

OBJECTIVE: To illustrate the imaging appearances of a spectrum of renal collision and composite tumors. Occurrence of collision and composite tumors in the genitourinary tract is rare compared to the usual occurrence of synchronous tumors. METHODS: Case studies were chosen that represent the different tumors. Analysis was made on both the imaging and the pathology if excision was performed. RESULTS: Presence of 2 different cell types can lead to confusing imaging findings, and biopsy or excision is typically needed for final diagnosis. Some composite tumors have a characteristic appearance on imaging based on their pathologic features. CONCLUSION: Familiarity with imaging findings may help radiologists include these tumors in their differential diagnosis.