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Purpose: Ameloblastoma is an odontogenic neoplasm whose overall mutational landscape has not been well characterized. We sought to characterize pathogenic mutations in ameloblastoma and their clinical and functional significance with an emphasis on the mitogen-activated protein kinase (MAPK) pathway.Experimental Design: A total of 84 ameloblastomas and 40 non-ameloblastoma odontogenic tumors were evaluated with a combination of BRAF V600E allele–specific PCR, VE1 immunohistochemistry, the Ion AmpliSeq Cancer Hotspot Panel, and Sanger sequencing. Efficacy of a BRAF inhibitor was evaluated in an ameloblastoma-derived cell line.Results: Somatic, activating, and mutually exclusive RAS–BRAF and FGFR2 mutations were identified in 88% of cases. Somatic mutations in SMO, CTNNB1, PIK3CA, and SMARCB1 were also identified. BRAF V600E was the most common mutation, found in 62% of ameloblastomas and in ameloblastic fibromas/fibrodentinomas but not in other odontogenic tumors. This mutation was associated with a younger age of onset, whereas BRAF wild-type cases arose more frequently in the maxilla and showed earlier recurrences. One hundred percent concordance was observed between VE1 immunohistochemistry and molecular detection of BRAF V600E mutations. Ameloblastoma cells demonstrated constitutive MAPK pathway activation in vitro. Proliferation and MAPK activation were potently inhibited by the BRAF inhibitor vemurafenib.Conclusions: Our findings suggest that activating FGFR2–RAS–BRAF mutations play a critical role in the pathogenesis of most cases of ameloblastoma. Somatic mutations in SMO, CTNNB1, PIK3CA, and SMARCB1 may function as secondary mutations. BRAF V600E mutations have both diagnostic and prognostic implications. In vitro response of ameloblastoma to a BRAF inhibitor suggests a potential role for targeted therapy. Clin Cancer Res; 20(21); 5517–26. ©2014 AACR.

APOBEC and AICDA expression after exposure to gefitinb.

Uracil-DNA glycosylase (UDG) hydrolysis assay.

Supplemental Figure S1. Sequence electropherograms and histopathology from representative cases with CTNNB1, PIK3CA, NRAS, FGFR2, SMARCB1, HRAS and SMO mutations.

AICDA CRISPR1 and CRISPR2 mutations.

Patients' clinical data.

Sensitivity of T790M ddPCR assay.

AICDA and RELB expression after TKI exposure was inhibited upon pretreatment with BAY11-7802.

Almost all patients with EGFR-driven lung cancer who are treated with EGFR tyrosine kinase inhibitors (TKI) develop resistance to treatment. A single base (c.2369C>T) transition mutation, EGFR T790M, is the most frequent resistance event after first-generation exposure to EGFR TKIs. Whether T790M mutation is acquired or is selected from a preexisting clone has been a matter of significant debate. In this study, we show that treatment with EGFR TKIs leads to activation of the NFκB pathway, which in turn induces expression of activation-induced cytidine deaminase (AICDA). In turn, AICDA causes deamination of 5-methylcytosine to thymine at position c.2369 to generate the T790M mutation. Pharmacologic inhibition of the NFκB pathway or knockout of AICDA decreased the frequency or prevented the development of T790M mutation, respectively. In addition, patients treated with first-line EGFR TKI displayed increased expression of AICDA and detection of the T790M mutation upon progression. These results identify the mechanism of T790M acquisition and present an opportunity to target the process to delay or prevent it.Significance:These findings identify the mechanism behind acquisition of a common resistance mutation to TKI treatment in lung cancer.

Deamination of Cytosine or 5-methylcytosine to Uracil or Thymine respectively.

Sinonasal Squamous Cell Carcinoma Clinical and Genotypic Data.

Supplementary Figure 1 from Loss of the hSNF5 Gene Concomitantly Inactivates p21CIP/WAF1 and p16INK4a Activity Associated with Replicative Senescence in A204 Rhabdoid Tumor Cells

Univariate Cox regression analysis for ISP progression to SNSCC, Multivariate Cox regression analysis for ISP progression to SNSCC, Summary of EGFR mutation status and clinicopathologic features of a large ISP cohort.

hSNF5, the smallest member of the SWI/SNF chromatin remodeling complex, is lost in most malignant rhabdoid tumors (MRT). In MRT cell lines, reexpression of hSNF5 induces G1 cell cycle arrest, elevated p16INK4a, and activated replicative senescence markers, such as β-galactosidase (β-Gal) and plasminogen activator inhibitor-1. To compare the replicative senescence caused by hSNF5 in A204 cells to normal cellular senescence, we examined the activation of both p16INK4a and p21CIP/WAF1. Analogous to normal cellular senescence, both p16INK4a and p21CIP/WAF1 were up-regulated following hSNF5 restoration. Furthermore, we found that hSNF5 bound the p16INK4a and p21CIP/WAF1 promoters, suggesting that it directly regulates transcription of these genes. Using p16INK4a RNA interference, we showed its requirement for the replicative senescence caused by hSNF5 but not the growth arrest. Instead, p21CIP/WAF1 remained activated by hSNF5 in the absence of high p16INK4a expression, apparently causing the growth arrest in A204. Interestingly, we also found that, in the absence of p16INK4a, reexpression of hSNF5 also increased protein levels of a second cyclin-dependent kinase (CDK) inhibitor, p18INK4c. However, our data show that lack of hSNF5 does not abrogate cellular responsiveness to DNA damage or growth-inhibitory factors. In summary, our studies suggest that hSNF5 loss may influence the regulation of multiple CDK inhibitors involved in replicative senescence.

Sinonasal Papilloma Clinical and Genotypic Data.

We identified urothelial tract biopsy and resection specimens with keratinizing squamous metaplasia (KSM), nonkeratinizing squamous metaplasia (NKSM), and urothelial and squamous carcinomas over a 20-yr period, focusing on cases with neurogenic lower urinary tract dysfunction (NLUTD) and/or those with spatial or temporal variation in sampling. TERT promoter mutations as assessed via allele-specific polymerase chain reaction were surprisingly common in our testing cohort, identified not only in 15 (94%) invasive cancer foci but also in 13 (68%) examples of KSM and seven (70%) examples of NKSM. TERT promoter mutations were present in 23 foci from NLUTD specimens and 11 foci from bladder diverticula, including in foci of KSM, NKSM, and unremarkable urothelium from cases with no clinical association with previous, concurrent, or subsequent cancer. Our demonstration of temporally and spatially persistent TERT promoter mutation in examples of KSM and NKSM in cases of bladder cancer and in morphologically benign cases with neurogenic dysfunction suggests a molecular mechanism by which such pre-neoplastic lesions can potentially progress and develop into overt carcinoma. Given the interest in TERT promoter mutations as a potential biomarker for the development of bladder cancer, these findings possibly explain the association between conditions with chronic urinary bladder injury (such as the natural history of NLUTD) and higher risk of bladder cancer. TERT promoter mutations may represent an early event in bladder cancer tumorogenesis, and our findings expand on the clinical ramifications and predictive value of TERT promoter mutations in this context. Patient summary Mutations in the TERT gene are the most common genetic changes in bladder cancer. We found that these mutations are also sometimes present in patients with chronic bladder irritation such as neurogenic bladder dysfunction and changes to the lining of the bladder that pathologists would consider “benign.” This finding might explain why such conditions are associated with the development of bladder cancer.

PURPOSE: The purpose of this exploratory study was to investigate the types of academic and health-related accommodations provided to adolescents and emerging adults with spina bifida aged 9-20 years. METHODS: Data were extracted from the paper and electronic records of transition-age youth enrolled in the study. Four open ended items involved content analysis. RESULTS: The most frequently identified accommodation was enrollment in special education classes in 47.7% of the charts. Other academic accommodations that were most often reported were adaptive physical education (n = 71, 39.9%), tutoring (n = 28; 15.7%), and home schooling (n = 21; 11.8%). Clean intermittent catheterization was the most frequently identified health-related accommodation provided by the school nurse/aide (n = 57; 32%).The largest percentage of requests for additional accommodations were made during the middle school grades (15; 54.8%) followed by high school (10; 32.2%). CONCLUSION: Findings demonstrated that persistent issues were identified by parents/adolescents regarding the provision of school-related accommodations. This is a relevant area for clinical practice to ensure students with special health care needs and those with spina bifida receive the academic and health-related accommodations in their Individualized Education Program/504 plans.

Health care transition is an expanding field of health care practice and research focused on facilitating adolescents and emerging adults with long-term conditions to transfer uninterruptedly from pediatric to adult health care services and to transition successfully into adulthood and beyond. There is a widespread need to develop and implement service models as approximately one million adolescents and emerging adults with long-term conditions transfer their care into the adult system and enter adulthood. The purpose of this article is to explore major issues associated with the current state of health care transition practice, research and ultimately policymaking and systems change. The prominent issues addressed in this article include the following. Defining clearly what constitutes models of health care transition practice as ambiguity exists with terminology used with concepts integral to health care transition. The indistinct meanings of health care transition terminology commonly used, such as transition, transfer, readiness, and preparation, need to be operationalized for widespread application. Furthermore, questions remain as to what goal-directed outcomes are expected within this field of practice and science.

Sinonasal papillomas are benign epithelial tumors of the sinonasal tract that are associated with a synchronous or metachronous sinonasal carcinoma in a subset of cases. Our group recently identified mutually exclusive EGFR mutations and human papillomavirus (HPV) infection in inverted sinonasal papillomas and frequent KRAS mutations in oncocytic sinonasal papillomas. We also demonstrated concordant mutational and HPV infection status in sinonasal papilloma-associated sinonasal carcinomas, confirming a clonal relationship between these tumors. Despite our emerging understanding of the oncogenic mechanisms driving formation of sinonasal papillomas, little is currently known about the molecular mechanisms of malignant progression to sinonasal carcinoma. In the present study, we utilized targeted next-generation DNA sequencing to characterize the molecular landscape of a large cohort of sinonasal papilloma-associated sinonasal carcinomas. As expected, EGFR or KRAS mutations were present in the vast majority of tumors. In addition, highly recurrent TP53 mutations, CDKN2A mutations, and/or CDKN2A copy-number losses were detected; overall, nearly all tumors (n = 28/29; 96.6%) harbored at least one TP53 or CDKN2A alteration. TERT copy-number gains also occurred frequently (27.6%); however, no TERT promoter mutations were identified. Other recurrent molecular alterations included NFE2L2 and PIK3CA mutations and SOX2, CCND1, MYC, FGFR1, and EGFR copy-number gains. Importantly, TP53 mutations and CDKN2A alterations were not detected in matched sinonasal papillomas, suggesting that these molecular events are associated with malignant transformation. Compared to aerodigestive tract squamous cell carcinomas from The Cancer Genome Atlas (TCGA) project, sinonasal papilloma-associated sinonasal carcinomas have a distinct molecular phenotype, including more frequent EGFR, KRAS, and CDKN2A mutations, TERT copy-number gains, and low-risk human papillomavirus (HPV) infection. These findings shed light on the molecular mechanisms of malignant progression of sinonasal papillomas and may have important diagnostic and therapeutic implications for patients with advanced sinonasal cancer.

Although there are a number of transitions of care initiatives that address specific needs as patients move across healthcare settings, adverse events still occur during handoffs. Transitions of care create periods of vulnerability for populations with complex needs that include communication gaps, medication changes, and poorly coordinated treatment plans, often without involving patients and their families. This paper outlines what nurses need to know to provide for safe transitions of care across the healthcare continuum. The theoretical basis for transitions of care at the macro level, examples of nurse-led models for transitions of care, and key activities and implications for nursing education and practice are described. A holistic framework for effective transitions of care across healthcare settings can guide nursing educators in the development of specific nursing competencies for transitions of care.

Digital health is a rapidly developing field which is positioned to transform the manner in which healthcare is delivered, especially amongst adolescents and young adults. In order to assess the efficacy of novel medical devices, clinicians and researchers often turn to the literature for guidance. Randomized control trials and the systematic reviews and meta-analyses that they inform are considered to be at the top of the evidence hierarchy. While they are excellent tools to identify and to summarize the best available evidence to answer a specific research question, they are poorly equipped to provide a more expansive understanding of the body of relevant literature in a timely manner. In this letter we discuss the utility of the scoping review, an underutilized style of academic writing designed to map key concepts in a body of literature. This method is ideal when reporting on the fast-paced field of digital medicine, as it allows for rapid synthesis of the available literature.

Fine needle aspiration (FNA) has become increasingly popular in the evaluation of lymph nodes for lymphoproliferative disorders, but there are limitations to accurate subclassification of lymphoma using morphology alone. This case aims to expand diagnostic considerations of large B-cell populations identified on FNA material. We also address the significance of Epstein-Barr virus (EBV) DNA in the workup of patients with suspected lymphoma by FNA.

The survival rates of youth and young adults (YYAs) diagnosed with long-term conditions have improved considerably as 90% now enter adulthood; health care transition planning (HCTP) has emerged as a nursing practice priority. The aim of this national online survey was to investigate the extent to which nurses, recruited from two major United States pediatric nursing organizations are involved with HCTP including assessing YYA self-management abilities (SMA). Findings of a 9-item assessment of self-management abilities subscale of the nurses’ role in HTCP tool are reported. The nurse respondents ( n = 1269), identified the most frequently assessed SMA was the YYAs’ ability to understand and speak about their condition and its treatment ( M = 2.3, SD = .89). The least frequently assessed was the YYAs’ ability to identify community advocates to help them become more independent ( M =1.5, SD = .90). Regression analysis identified significant predictors of the frequency nurses assess YYA for SMA included nurses’ level of knowledge, perceived level of importance, HCTP and skills identified in job description, and caring for YYA. Findings indicate HCTP care advancements will necessitate HCTP training and development of nurse-led service efforts to facilitate optimal outcomes for YYA.

Nurses have important roles as members of the healthcare transition (HCT) planning interdisciplinary team. Nursing's scope of practice and framework of care brings a distinctive and complementary approach to this expanding field in pediatric care. It is therefore relevant to better understand the extent to which pediatric nurses are involved with the provision of HCT services and model development.This was a qualitative analysis of a national survey of pediatric nurses. A thematic iterative process was used to code data. Three coders separately analyzed responses and then met to compare and discuss until a final list of codes was achieved. The codes were further analyzed until themes and subthemes emerged. Throughout the process, disagreements were discussed and resolved until consensus was achieved.A sample of 1814 pediatric nurses and nurse practitioners from two US professional organizations participated in this national survey to gather data on their involvement in HCT planning. This survey contained 17 items, one of which was an open-ended question stating: Is there anything else you would like to share about your role with the population of transitioning youth and young adults with chronic illness and/or disability? The analysis of responses provided by 154 nurses is presented. Initial coding resulted in 11 categories of data. Four major themes, including four subthemes, emerged from the analysis of responses: Support for the need for transition (subtheme: Nursing involvement); Guidance needed for professional practice (subtheme: Types of guidelines and training); Lack of service linkages to adult providers; and Difficulty letting go (two subthemes: Pediatric providers; Parents).These findings indicated strong support for the need of HCT services and the importance of nursing involvement. However, challenges to HCT implementation were identified that include systemic, psychosocial, and educational barriers. As this field of practice and research continues to grow, it is important that pediatric nurses recognize the opportunities to have a clinical voice to develop nurse-led HCT services and programs.

The purpose was to identify the educational needs of pediatric nurses and pediatric nurse practitioners providing direct care to transition-aged youth with chronic illness and disability and to identify strategies to develop health care transition planning (HCTP) expertise.Mixed-methods descriptive analyses were performed on survey data extracted from a larger national study exploring the provision of HCTP activities performed by nurses of two pediatric nursing professional organizations.Items querying educational needs were completed by 1,162 pediatric nurses serving in advanced practice and staff roles. Twenty percent reported having specialized HCTP education. Of which more than half received it outside of the workplace. Factor analysis revealed two constructs explaining 73.4% of the variance in nurses' reported level of knowledge.HCTP education and the development of nurse-led services to facilitate optimal health care transitions outcomes are necessitated. Academia and service have a shared responsibility in educating nurses.

Spina bifida (SB) is a condition resulting from the improper closure of the neural tube and vertebral column during fetal development. While patients' life expectancy and quality of life have improved dramatically due to medical advances, children continue to experience health-related issues that often require hospitalizations.The association among sociodemographic and clinical characteristics with potentially preventable hospitalizations (PPH) in children and youth with myelomeningocele type SB was investigated in this cross-sectional study.Chart reviews and data extraction were conducted on 108 children and youth, ages 1 month to 21 years, admitted for PPH in a regional children's academic medical center between May 2017 and July 2019. Sociodemographic variables included sex, age, type of insurance and ethnicity. Clinical variables included level of lesion, ambulation status, shunt dependency and selected diagnostic categories. Univariate, bivariate, and multivariate analyses were conducted to identify factors associated with PPH.Factors associated with PPH included being male, ages 5-18 years, low lumbar level lesions, non-ambulatory, with public insurance, Hispanic and shunt dependent. Most hospitalizations (73%) were for neurologic or urologic conditions. Factors independently associated with PPH were ethnicity for urologic conditions, being ambulatory for metabolic conditions, and age for gastroenterology conditions.Selected demographic and clinical variables were found to be associated with PPH of children and youth with myelomeningocele-type SB. The most common reasons for PPH were shunt malfunctions and urinary tract infections, consistent with other studies.

Primary Central Nervous System Lymphoma (PCNSL) is a lymphoid malignancy of the brain that occurs in ~1500 patients per year in the US. PCNSL can spread to the vitreous and retina, where it is known as vitreoretinal lymphoma (VRL). While confirmatory testing for diagnosis is dependent on invasive brain tissue or cerebrospinal fluid sampling, the ability to access the vitreous as a proximal biofluid for liquid biopsy to diagnose PCNSL is an attractive prospect given ease of access and minimization of risks and complications from other biopsy strategies. However, the extent to which VRL, previously considered genetically identical to PCNSL, resembles PCNSL in the same individual with respect to genetic alterations, diagnostic strategies, and precision-medicine based approaches has hitherto not been explored. Furthermore, the degree of intra-patient tumor genomic heterogeneity between the brain and vitreous sites has not been studied. In this work, we report on targeted DNA next-generation sequencing (NGS) of matched brain and vitreous samples in two patients who each harbored VRL and PCSNL. Our strategy showed enhanced sensitivity for molecular diagnosis confirmation over current clinically used vitreous liquid biopsy methods. We observed a clonal relationship between the eye and brain samples in both patients, which carried clonal CDKN2A deep deletions, a highly recurrent alteration in VRL patients, as well as MYD88 p.L265P activating mutation in one patient. Several subclonal alterations, however, in the genes SETD2, BRCA2, TERT, and broad chromosomal regions showed heterogeneity between the brain and the eyes, between the two eyes, and among different regions of the PCNSL brain lesion. Taken together, our data show that NGS of vitreous liquid biopsies in PCNSL patients with VRL highlights shared and distinct genetic alterations that suggest a common origin for these lymphomas, but with additional site-specific alterations. Liquid biopsy of VRL accurately replicates the findings for PCNSL truncal (tumor-initiating) genomic alterations; it can also nominate precision medicine interventions and shows intra-patient heterogeneity in subclonal alterations. To the best of our knowledge, this study represents the first interrogation of genetic underpinnings of PCNSL with matched VRL samples. Our findings support continued investigation into the utility of vitreous liquid biopsy in precision diagnosis and treatment of PCNSL/VRL.

BACKGROUND: Ethnic disparities in continence rates in spina bifida (SB) have been studied regionally but not nationally. National SB Patient Registry (NSBPR) data were analyzed to explore differences in prevalence of bowel and bladder continence and interventions between Hispanics/Latinos and others. METHODS: Participants 5 to 21 years were categorized into Hispanic/Latino and non-Hispanic/non-Latino. Bladder/bowel continence was defined as dry/no involuntary stool leakage during the day or none/⩽ monthly incontinence. Chi-square test, Wilcoxon Two Sample Test, and generalized estimating equation (GEE) were used for statistical analysis. RESULTS: Twenty-five percent of the 4,364 patients were Hispanic/Latino. At their most recent clinic visit, Hispanics/Latinos demonstrated lower rates of urinary continence (38.6% vs. 44.9%; p = 0.0003), bowel continence (43.9% vs. 55.8%, p < 0.0001), private insurance (p < 0.0001), bowel (p < 0.0001) or bladder surgeries (p = 0.0054), and more vesicostomies (p = 0.0427) compared to others. In multiple GEE models, Hispanic/Latino participants demonstrated lower odds of bowel continence as compared to non-Hispanic/non-Latino participants (estimated odds ratio, 0.82, 95% CI, 0.72–0.94, p = 0.0032). CONCLUSIONS: After controlling for covariates, Hispanics/Latinos with SB are less likely to report bowel continence. Clinicians are encouraged to consider the risk of negative health disparities for Hispanic patients with SB and work to mitigate this risk.

Objective The objective of this scoping review is to identify the scope of literature published on the use of smart devices for interventions in pediatric asthma, including low income and culturally diverse populations. Introduction Childhood asthma results in substantial morbidity and costs that pose a significant burden to families and healthcare systems. Low-income and culturally diverse pediatric populations have increased rates of morbidity and mortality compared to higher income families. Smart devices have the potential to improve pediatric asthma health outcomes and reduce health disparities. Inclusion criteria This scoping review will consider studies with participants who are children, adolescents and young adults with the diagnosis of asthma (ages zero to 26 years). Studies of children and adolescents and young adults with asthma may include adult participants who manage and/or supervise asthma care or provide asthma instruction. Methods This scoping review will be conducted using the Ovid MEDLINE, Embase, Cochrane Library, CINAHL, Web of Science, PsycINFO, ERIC, and both Compendex and Inspec through Engineering Village databases. Gray literature searches will also be conducted. Studies will be reviewed independently by two reviewers, with any conflicts adjudicated by a third member. Data extracted will be presented in a tabular format with an accompanying narrative.

Purpose Youth and young adults (YYA) with chronic illness and/or disability (CID) face numerous challenges in transition from pediatric to adult health care. Established evidence supports interdisciplinary team approaches to preparing youth and families for transition and transfer. The purpose of this national survey was to address a gap in current knowledge specific to pediatric nursing professionals' roles and responsibilities in health care transition planning (HCTP). Methodology A quantitative descriptive study using a survey questionnaire validated by experts in the field investigated respondents' role in HCTP, inclusion of HCTP in job description, levels of HCTP knowledge, and ratings of importance of HCTP elements. A volunteer sample of 1814 respondents was drawn from two professional organizations. Results Over 64% of respondents performed HCTP activities related to complex chronic illness management. Only 18% reported specialized training in HCTP. The highest-ranking items in regard to perceived importance were educating and supporting disease self-management and speaking with families about complex needs. Predictors of perceived importance were role, inclusion of transition planning in a job description, percentage of time in direct care, caring for those aged 14 years and older, and level of knowledge about HCTP. Conclusions The findings highlight key aspects of the pediatric nurse role in HCTP and identify specific elements that can be addressed to support future HCTP role development. Practice implications Pediatric nurses perform a vital role in HCTP for YYA with CID that may be enhanced with the inclusion of HCTP activities in job descriptions and specialized interdisciplinary HCTP training related to this emerging and growing population.

In recent years, a novel small round cell sarcoma harboring EWSR1-NFATC2 translocation with immunomorphologic overlap with Ewing sarcoma (ES), myoepithelial tumors, and extraskeletal myxoid chondrosarcoma has emerged. There has not been a case series devoted to describing its detailed clinicopathologic and immunohistochemical characteristics. Six sarcomas harboring EWSR1-NFATC2 fusion transcripts by reverse transcription polymerase chain reaction and amplification of the fusion gene by fluorescence in situ hybridization were identified. The patients were 5 adult men and 1 adult woman. Three were primary bone tumors of the radius and 3 were primary soft tissue tumors. Most tumors showed monomorphic round to epithelioid cells in anastomosing cords and abundant myxohyaline to collagenous extracellular matrix. Two tumors had large areas of a solid, matrix-poor histomorphology. All tumors stained for CD99 and NKX2.2; while EMA, dot-like cytokeratin, and focal WT-1 and SMA were present in some tumors. All but 1 tumor showed poor histologic and radiologic responses to neoadjuvant ES-specific chemotherapy. Local or distant recurrences happened in 4 cases. EWSR1-NFATC2 sarcoma is a novel translocation-associated sarcoma. It presents as either a primary bone or soft tissue tumor, usually exhibits distinctive histopathologic features, and has predilection for long bones of adult men. It consistently shows recurrent fusion gene amplification readily detectable by EWSR1 breakapart fluorescence in situ hybridization, which serves as a diagnostic surrogate. It has potential for local and distant recurrence and histologic progression, and is resistant to Ewing sarcoma-specific chemotherapy.

BackgroundCompelling evidence indicates that gaps in quality, safety, and experiences occur when patients encounter transitions across the care continuum. Differences in the organization of healthcare services as well as disparities in health across the globe, may have a unique impact on processes associated with transitions of care for client populations.PurposeIncreased attention to the concept of transitions of care has resulted in disparate meanings and lack of clarity about its nature. Therefore, the purpose of this manuscript is to address this knowledge gap by analyzing the concept of transitions of care at the population level.MethodologyTo address the knowledge gap of what constitutes transitions of care at the population level, a concept analysis was done guided by the methodology of Walker and Avant. A comprehensive search of the literature yielded a small but relevant number of publications.ResultsThis analysis identified four defining attributes, together with antecedents and consequences of transitions of care at the macro-system level of healthcare. A synthesized definition of transitions of care was developed.Implications for PracticeThis analysis provides conceptual clarity for the concept of transitions of care at the macro-system level of care. It can be used to guide the development of a middle-range theory to inform clinical practice and health policy.