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A subset of desmoplastic melanomas (DMs) can show extensive morphologic and immunohistochemical overlap with cutaneous diffuse-type neurofibroma. Neurofibroma-like desmoplastic melanoma (NFLDM) thus poses a significant diagnostic pitfall because the clinical implications of these 2 entities differ dramatically. A series of 17 DMs, including 5 cases of NFLDM, were compared with a cohort of 53 cutaneous diffuse-type neurofibromas to explore the utility of molecular testing in the differential diagnosis between NFLDM and neurofibroma and to determine potentially useful morphologic features in this differential diagnosis. Unlike NFLDM, cutaneous diffuse-type neurofibromas: (1) rarely feature intratumoral or peritumoral lymphoid aggregates, (2) consistently harbor an intrinsic stromal support vasculature composed of evenly spaced capillary-sized vessels, and (3) infiltrate adjacent adipose tissue in a dermatofibrosarcoma protuberans-like manner with a complete lack of chronic inflammation or fat necrosis at the leading edge of the tumor. Conversely, DMs, including NFLDM: (1) do not contain Wagner-Meissner bodies, (2) often induce fat necrosis and/or chronic inflammation at the interface with adjacent fibroadipose tissue, (3) lack the intrinsic capillary-sized stromal vasculature observed in most neurofibromas, and (4) may harbor foci of perineuriomatous differentiation, mimicking a hybrid nerve sheath tumor. Any deviation from the expected clinical or morphologic features of cutaneous diffuse-type neurofibroma should raise suspicion for NFLDM. Although not entirely sensitive or specific, molecular testing can help to support the diagnosis of NFLDM by demonstrating genetic abnormalities associated with melanoma, including a UV-light-induced mutational signature, high tumor mutational burden, and/or chromosomal copy number alterations typical of melanoma., Competing Interests: ​Conflicts of Interest and Source of Funding: J.C.D. is a co-founder of Belay Diagnostics and holds stock in the company. For the remaining authors, none were declared., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Using microRNAs (miRNAs) as potential circulating biomarkers in diagnosing and treating glioblastoma (GBM) has garnered a lot of scientific and clinical impetus in the past decade. As an aggressive primary brain tumor, GBM poses challenges in early detection and effective treatment with significant current diagnostic constraints and limited therapeutic strategies. MiRNA dysregulation is present in GBM. The intricate involvement of miRNAs in altering cell proliferation, invasion, and immune escape makes them prospective candidates for identifying and monitoring GBM diagnosis and response to treatment. These miRNAs could play a dual role, acting as both potential diagnostic markers and targets for therapy. By modulating the activity of various oncogenic and tumor-suppressive proteins, miRNAs create opportunities for precision medicine and targeted therapies in GBM. This review centers on the critical role and function of circulating miRNA biomarkers in GBM diagnosis and treatment. It highlights their significance in providing insights into disease progression, aiding in early diagnosis, and potential use as targets for novel therapeutic interventions. Ultimately, the study of miRNA would contribute to improving patient outcomes in the challenging landscape of GBM management.

Disinhibition during early stages of Alzheimer's disease is postulated to cause network dysfunction and hyperexcitability leading to cognitive deficits. However, the underlying molecular mechanism remains unknown. Here we show that, in mouse lines carrying Alzheimer's disease-related mutations, a loss of neuronal membrane potassium-chloride cotransporter KCC2, responsible for maintaining the robustness of GABAA-mediated inhibition, occurs pre-symptomatically in the hippocampus and prefrontal cortex. KCC2 downregulation was inversely correlated with the age-dependent increase in amyloid-β 42 (Aβ42). Acute administration of Aβ42 caused a downregulation of membrane KCC2. Loss of KCC2 resulted in impaired chloride homeostasis. Preventing the decrease in KCC2 using long term treatment with CLP290 protected against deterioration of learning and cortical hyperactivity. In addition, restoring KCC2, using short term CLP290 treatment, following the transporter reduction effectively reversed spatial memory deficits and social dysfunction, linking chloride dysregulation with Alzheimer's disease-related cognitive decline. These results reveal KCC2 hypofunction as a viable target for treatment of Alzheimer's disease-related cognitive decline; they confirm target engagement, where the therapeutic intervention takes place, and its effectiveness., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Guarantors of Brain.)

The analysis of cell-free DNA (cfDNA) from plasma offers great promise for the earlier detection of cancer. At present, changes in DNA sequence, methylation, or copy number are the most sensitive ways to detect the presence of cancer. To further increase the sensitivity of such assays with limited amounts of sample, it would be useful to be able to evaluate the same template molecules for all these changes. Here, we report an approach, called MethylSaferSeqS, that achieves this goal, and can be applied to any standard library preparation method suitable for massively parallel sequencing. The innovative step was to copy both strands of each DNA-barcoded molecule with a primer that allows the subsequent separation of the original strands (retaining their 5-methylcytosine residues) from the copied strands (in which the 5-methylcytosine residues are replaced with unmodified cytosine residues). The epigenetic and genetic alterations present in the DNA molecules can then be obtained from the original and copied strands, respectively. We applied this approach to plasma from 265 individuals, including 198 with cancers of the pancreas, ovary, lung, and colon, and found the expected patterns of mutations, copy number alterations, and methylation. Furthermore, we could determine which original template DNA molecules were methylated and/or mutated. MethylSaferSeqS should be useful for addressing a variety of questions relating genetics and epigenetics.

Objective: To fully address physician burnout, academic medical centers need cultures that promote well-being. One observed driver of a culture of wellness is perceived appreciation. The authors identified several contributors to perceived appreciation among faculty at a large, metropolitan academic institution through use of a novel survey., Methods: The authors surveyed clinical faculty in five departments: psychiatry, emergency medicine, internal medicine, thoracic surgery, and radiology. Two open-ended response questions assessed sources of perceived and lack of perceived appreciation in narrative form. The authors also collected data on gender and department identity. Grounded theory methodology was used to analyze the narrative responses and design thinking to brainstorm specific recommendations based on the main themes identified., Results: A total of 179 faculty respondents filled out the survey for an overall response rate of 29%. Major drivers of perceived appreciation were patient and families (42%); physician, trainee and non-physician colleagues (32.7%); chairs (10%); and compensation (3.3%). Major drivers of perceived lack of appreciation were disrespect for time and skill level, including inadequate staffing (30%); devaluation by a physician colleague, chief of one's service or the chair (29%); poor communication and transparency (13%); and patient and family anger (6%)., Conclusions: Opportunities to improve perceived appreciation include structured communication of patient gratitude, community building programs, top of licensure initiatives and accountability for physician wellness, and inclusivity efforts from organizational leaders., (© 2021. Academic Psychiatry.)

Rationale and Objectives: Relatively little data exist on factors associated with radiologists' burnout versus other medical specialties. We compared self-reported burnout among academic medical center radiologists versus nonradiologist peers to inform initiatives to increase wellbeing and professional satisfaction., Materials and Methods: In 2017, our large urban academic medical center administered the Stanford Physician Wellness Survey to faculty in fifteen clinical departments (fourteen academic, one community-based). Faculty rated burnout via Likert scale (0-no burnout; 1-occasional stress/no burnout; 2-one or more burnout symptoms; 3-persistent burnout symptoms; 4-completely burned out); burnout defined as >=2. Responses in 11 domains (professional fulfillment, emotional exhaustion, interpersonal disengagement, sleep difficulties, self-compassion, negative work impact on personal relations, perceived appreciation, control over schedule, organizational/personal values alignment, electronic health record, perceived quality of supervisory leadership) compared radiologists versus nonradiologists for association with burnout, using Whitney-Mann U test to calculate Z scores., Results: There was no significant difference in overall self-reported burnout between radiologists and nonradiologists, nor in self-rating for emotional exhaustion, interpersonal disengagement, self-compassion, control over schedule, organizational/personal values alignment, or electronic health record experience. Radiologists had significantly lower self-rating for work happiness (Z = -2.669, p = 0.0076), finding work meaningful (Z = -2.77351, p = 0.0055), perceiving physicians as highly valued (Z = -2.5486, p = 0.0108), and believing leadership treated them with respect and dignity (Z = -3.44149, p = 0.0006)., Conclusion: Compared to nonradiologist colleagues, radiologists were less likely to find work meaningful and more likely to feel unhappy and undervalued in the workplace and by leadership. Initiatives to increase perceived appreciation, leadership relationships, and meaningfulness of work for radiologists may reduce burnout., (Copyright © 2020 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.)

Because cancer is caused by an accumulation of genetic mutations, mutant DNA released by tumors can be used as a highly specific biomarker for cancer. Although this principle was described decades ago, the advent and falling costs of next-generation sequencing have made the use of tumor DNA as a biomarker increasingly practical. This review surveys the use of cellular and cell-free DNA for the detection of cancer, with a focus on recent technological developments and applications to solid tumors. It covers ( a ) key principles and technology enabling the highly sensitive detection of tumor DNA; ( b ) assessment of tumor DNA in plasma, including for genotyping, minimal residual disease detection, and early detection of localized cancer; ( c ) detection of tumor DNA in body cavity fluids, such as urine or cerebrospinal fluid; and ( d ) challenges posed to the use of tumor DNA as a biomarker by the phenomenon of benign clonal expansions.

Objective: Determine predictors of self-reported burnout among academic radiologists., Methods: In 2017, radiologists at an urban medical center completed the Stanford Wellness Survey, rating burnout via Likert scale (0: no burnout; 1: occasional stress, no burnout; 2: one or more burnout symptoms; 3: persistent burnout symptoms; 4: completely burned out). Univariate analyses assessed age, gender, family situation, clinical versus research focus, and academic rank for association with burnout (Likert scale ≥ 2). Responses in 11 domains querying definitions of burnout (professional fulfillment, emotional exhaustion, interpersonal disengagement), individual factors (sleep-related impairment, self-compassion, negative work impact on personal relationships), institutional factors (perceived appreciation, control over schedule, organizational or personal values alignment, electronic health record experience, supervisor's leadership quality) were evaluated for association with burnout, using χ 2 and logistic regression to calculate odds ratios (ORs)., Results: In 159 of 204 (77.9%) completed radiologist surveys, 35.2% (56 of 159) reported burnout. Age < 40 years (P = .0068) and clinical focus (P = .0111) were significantly associated with burnout. In univariate analysis, all domains except electronic health record were statistically significant: emotional exhaustion (OR = 1.93, P < .0001); professional fulfillment (OR = 0.78, P < .0001); self-compassion (OR = 1.36, P < .0001); perceived appreciation (OR = 0.78, P < .0001); sleep-related impairment (OR = 1.20, P < .0001); supervisor's leadership quality (OR = 0.91, P < .0001); interpersonal disengagement (OR = 1.31, P < .0001); organizational or personal values alignment (OR = 0.87, P = .0004); negative work impact on personal relationships (OR = 1.10, P = .0070); control over schedule (OR = 0.80, P = .0054); electronic health record experience (OR=1.03, P = .5392)., Discussion: Nearly all questions significantly predicted self-reported burnout, observed in over one-third of academic radiologists. Younger age and clinical focus were associated with burnout. Initiatives targeting individual factors (eg, sleep impairment, self-compassion) and institutional factors (eg, physician appreciation, leadership-faculty interactions) may reduce burnout., (Copyright © 2020. Published by Elsevier Inc.)

Importance: Sleep-related impairment in physicians is an occupational hazard associated with long and sometimes unpredictable work hours and may contribute to burnout and self-reported clinically significant medical error., Objective: To assess the associations between sleep-related impairment and occupational wellness indicators in physicians practicing at academic-affiliated medical centers and the association of sleep-related impairment with self-reported clinically significant medical errors, before and after adjusting for burnout., Design, Setting, and Participants: This cross-sectional study used physician wellness survey data collected from 11 academic-affiliated medical centers between November 2016 and October 2018. Analysis was completed in January 2020. A total of 19 384 attending physicians and 7257 house staff physicians at participating institutions were invited to complete a wellness survey. The sample of responders was used for this study., Exposures: Sleep-related impairment., Main Outcomes and Measures: Association between sleep-related impairment and occupational wellness indicators (ie, work exhaustion, interpersonal disengagement, overall burnout, and professional fulfillment) was hypothesized before data collection. Assessment of the associations of sleep-related impairment and burnout with self-reported clinically significant medical errors (ie, error within the last year resulting in patient harm) was planned after data collection., Results: Of all physicians invited to participate in the survey, 7700 of 19 384 attending physicians (40%) and 3695 of 7257 house staff physicians (51%) completed sleep-related impairment items, including 5279 women (46%), 5187 men (46%), and 929 (8%) who self-identified as other gender or elected not to answer. Because of institutional variation in survey domain inclusion, self-reported medical error responses from 7538 physicians were available for analyses. Spearman correlations of sleep-related impairment with interpersonal disengagement (r = 0.51; P < .001), work exhaustion (r = 0.58; P < .001), and overall burnout (r = 0.59; P < .001) were large. Sleep-related impairment correlation with professional fulfillment (r = -0.40; P < .001) was moderate. In a multivariate model adjusted for gender, training status, medical specialty, and burnout level, compared with low sleep-related impairment levels, moderate, high, and very high levels were associated with increased odds of self-reported clinically significant medical error, by 53% (odds ratio, 1.53; 95% CI, 1.12-2.09), 96% (odds ratio, 1.96; 95% CI, 1.46-2.63), and 97% (odds ratio, 1.97; 95% CI, 1.45-2.69), respectively., Conclusions and Relevance: In this study, sleep-related impairment was associated with increased burnout, decreased professional fulfillment, and increased self-reported clinically significant medical error. Interventions to mitigate sleep-related impairment in physicians are warranted.

Objective: To measure self-valuation, involving constructive prioritization of personal well-being and a growth mindset perspective that seeks to learn and improve as the primary response to errors, in physicians and evaluate its relationship with burnout and sleep-related impairment., Methods: We analyzed cross-sectional survey data collected between July 1, 2016, and October 31, 2017, from 5 academic medical centers in the United States. All faculty and medical-staff physicians at participating organizations were invited to participate. The self-valuation scale included 4 items measured on a 5-point (0-4) Likert scale (summative score range, 0-16). The self-valuation scale was developed and pilot tested in a sample of 250 physicians before inclusion in the multisite wellness survey, which also included validated measures of burnout and sleep-related impairment., Results: Of the 6189 physicians invited to participate, 3899 responded (response rate, 63.0%). Each 1-point score increase in self-valuation was associated with -1.10 point lower burnout score (95% CI, -1.16 to -1.05; standardized β=-0.53; P<.001) and 0.81 point lower sleep-related impairment score (95% CI, -0.85 to -0.76; standardized β=-0.47; P<.001), adjusting for sex and medical specialty. Women had lower self-valuation (Cohen d=0.30) and higher burnout (Cohen d=0.22) than men. Lower self-valuation scores in women accounted for most of the sex difference in burnout., Conclusion: Low self-valuation among physicians is associated with burnout and sleep-related impairment. Further research is warranted to develop and test interventions that increase self-valuation as a mechanism to improve physician well-being., (Copyright © 2019 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.)

Circulating tumor DNA (ctDNA) is a component of cell-free DNA that is shed by malignant tumors into the bloodstream and other bodily fluids. Levels of ctDNA are typically low, particularly in patients with localized disease, requiring highly sophisticated methods for detection and quantification. Multiple liquid biopsy methods have been developed for ctDNA analysis in solid tumor malignancies and are now enabling detection and assessment of earlier stages of disease, post-treatment molecular residual disease (MRD), resistance to targeted systemic therapy, and tumor mutational burden. Understanding ctDNA biology, mechanisms of release, and clearance and size characteristics, in conjunction with the application of molecular barcoding and targeted error correction, have increased the sensitivity and specificity of ctDNA detection techniques. Combinatorial approaches including integration of ctDNA data with circulating protein biomarkers may further improve assay sensitivity and broaden the scope of ctDNA applications. Circulating viral DNA may be utilized to monitor disease in some virally induced malignancies. In spite of increasingly accurate methods of ctDNA detection, results need to be interpreted with caution given that somatic mosaicisms such as clonal hematopoiesis of indeterminate potential (CHIP) may give rise to genetic variants in the bloodstream unrelated to solid tumors, and the limited concordance observed between different commercial platforms. Overall, highly precise ctDNA detection and quantification methods have the potential to transform clinical practice via non-invasive monitoring of solid tumor malignancies, residual disease detection at earlier timepoints than standard clinical and/or imaging surveillance, and treatment personalization based on real-time assessment of the tumor genomic landscape.

Current regimens for the detection and surveillance of bladder cancer are invasive and have suboptimal sensitivity. Here, we present a novel high-throughput sequencing (HTS) method for detection of urine tumor DNA (utDNA) called utDNA CAPP-Seq (uCAPP-Seq) and apply it to 67 healthy adults and 118 patients with early-stage bladder cancer who had urine collected either prior to treatment or during surveillance. Using this targeted sequencing approach, we detected a median of 6 mutations per patient with bladder cancer and observed surprisingly frequent mutations of the PLEKHS1 promoter (46%), suggesting these mutations represent a useful biomarker for detection of bladder cancer. We detected utDNA pretreatment in 93% of cases using a tumor mutation-informed approach and in 84% when blinded to tumor mutation status, with 96% to 100% specificity. In the surveillance setting, we detected utDNA in 91% of patients who ultimately recurred, with utDNA detection preceding clinical progression in 92% of cases. uCAPP-Seq outperformed a commonly used ancillary test (UroVysion, P = 0.02) and cytology and cystoscopy combined ( P ≤ 0.006), detecting 100% of bladder cancer cases detected by cytology and 82% that cytology missed. Our results indicate that uCAPP-Seq is a promising approach for early detection and surveillance of bladder cancer. SIGNIFICANCE: This study shows that utDNA can be detected using HTS with high sensitivity and specificity in patients with early-stage bladder cancer and during post-treatment surveillance, significantly outperforming standard diagnostic modalities and facilitating noninvasive detection, genotyping, and monitoring. This article is highlighted in the In This Issue feature, p. 453 ., (©2018 American Association for Cancer Research.)

Background: Cell-free DNA (cfDNA) diagnostics are emerging as a new paradigm of disease monitoring and therapy management. The clinical utility of these diagnostics is relatively limited by a low signal-to-noise ratio, such as with low allele frequency (AF) mutations in cancer. While enriching for rare alleles to increase their AF before sample analysis is one strategy that can greatly improve detection capability, current methods are limited in their generalizability, ease of use, and applicability to point mutations., Methods: Leveraging the robust single-base-pair specificity and generalizability of the CRISPR associated protein 9 (Cas9) system, we developed a deactivated Cas9 (dCas9)-based method of minor-allele enrichment capable of efficient single-target and multiplexed enrichment. The dCas9 protein was complexed with single guide RNAs targeted to mutations of interest and incubated with cfDNA samples containing mutant strands at low abundance. Mutation-bound dCas9 complexes were isolated, dissociated, and the captured DNA purified for downstream use., Results: Targeting the 3 most common epidermal growth factor receptor mutations (exon 19 deletion, T790M, L858R) found in non-small cell lung cancer (NSCLC), we achieved >20-fold increases in AF and detected mutations by use of qPCR at an AF of 0.1%. In a cohort of 18 NSCLC patient-derived cfDNA samples, our method enabled detection of 8 out of 13 mutations that were otherwise undetected by qPCR., Conclusions: The dCas9 method provides an important application of the CRISPR/Cas9 system outside the realm of genome editing and can provide a step forward for the detection capability of cfDNA diagnostics., (© 2017 American Association for Clinical Chemistry.)

Identifying molecular residual disease (MRD) after treatment of localized lung cancer could facilitate early intervention and personalization of adjuvant therapies. Here, we apply cancer personalized profiling by deep sequencing (CAPP-seq) circulating tumor DNA (ctDNA) analysis to 255 samples from 40 patients treated with curative intent for stage I-III lung cancer and 54 healthy adults. In 94% of evaluable patients experiencing recurrence, ctDNA was detectable in the first posttreatment blood sample, indicating reliable identification of MRD. Posttreatment ctDNA detection preceded radiographic progression in 72% of patients by a median of 5.2 months, and 53% of patients harbored ctDNA mutation profiles associated with favorable responses to tyrosine kinase inhibitors or immune checkpoint blockade. Collectively, these results indicate that ctDNA MRD in patients with lung cancer can be accurately detected using CAPP-seq and may allow personalized adjuvant treatment while disease burden is lowest. Significance: This study shows that ctDNA analysis can robustly identify posttreatment MRD in patients with localized lung cancer, identifying residual/recurrent disease earlier than standard-of-care radiologic imaging, and thus could facilitate personalized adjuvant treatment at early time points when disease burden is lowest. Cancer Discov; 7(12); 1394-403. ©2017 AACR. See related commentary by Comino-Mendez and Turner, p. 1368 This article is highlighted in the In This Issue feature, p. 1355 ., (©2017 American Association for Cancer Research.)

Background: Mucinous cystic neoplasms (MCNs) of the pancreas present a management conundrum. The majority are benign but all are resected due to their malignant potential. Recent studies have recommended nonsurgical management. In the current study, the authors analyzed the preoperative imaging, cytology, and cyst fluid characteristics of 136 histologically confirmed MCNs to assess predictors of a high-risk (HR) cyst for surgical triage., Methods: MCNs resected at the Massachusetts General Hospital between 1990 and 2014 formed the study cohort. Patient demographics, cyst size, and mural nodules (MNs) by endoscopic ultrasound, cytology, and cyst fluid carcinoembryonic antigen and amylase levels were correlated with histological grade. A HR cyst was defined as high-grade dysplasia or invasive carcinoma on histology. Performance characteristics were assessed for each parameter, with a cyst size ≥3 cm or a MN on imaging and malignant cytology considered to be "true-positive" results for predicting malignancy., Results: Only 15 of the 136 cysts had HR histology (11%). On average, patients with HR cysts were older than those with low-risk cysts (55 years vs 49 years, respectively). High-grade cytology was the most accurate predictor of malignancy (95%) followed by MN and cyst size together (88%) and MN alone (83%). The average carcinoembryonic antigen level (in ng/mL) increased with the grade of dysplasia but the ranges overlapped between low risk and HR cysts., Conclusions: To the authors' knowledge, the current study is the largest series to date analyzing the cytological features of histologically confirmed MCN. Cytology is insensitive but very specific for detecting a HR MCN and outperformed imaging for the detection of HR MCN. Endoscopic ultrasound-guided fine-needle aspiration and cytology should be performed on any clinically suspected MCN that is being considered for conservative management. Cancer Cytopathol 2017;125:169-177. © 2016 American Cancer Society., (© 2016 American Cancer Society.)

Background: The diagnosis of a pancreatic cyst as mucinous or high-risk dictates the need for follow-up or surgery. Molecular analysis of aspirated pancreatic cyst fluid (PCF) can provide valuable information not obtained by carcinoembryonic antigen (CEA) analysis or cytology., Methods: All patients who underwent molecular analysis of PCF between March 2013 and June 2015 were reviewed, including pathology, imaging, and follow-up. Molecular testing was performed using a patented, anchored multiplex polymerase chain reaction next-generation sequencing (NGS) platform, which sequenced numerous hotspots in 39 genes linked with malignancy. Performance of NGS and cytology was calculated using final outcome, as determined by clinicopathologic follow-up., Results: The study cohort included 113 PCFs from 105 patients. In total, 119 variants were detected in 67 PCFs (59%). Variants were more common in intraductal papillary mucinous neoplasms (IPMNs)/cancer than in nonmucinous cysts (P < .005). The inclusion of v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS)/guanine nucleotide-binding protein (GNAS) variants improved the classification of IPMNs as mucinous from 50% by microscopy to 100%. Seventy-five percent of cancers had high-grade atypia versus 0% of IPMNs and nonmucinous cysts (P < .002). Variants in tumor protein 53 (TP53), SMAD family member 4 (SMAD4), cyclin-dependent kinase inhibitor 2A (CDKN2A), and notch1 (NOTCH1) were detected only in malignant cysts. Cytology was similarly specific (100%) for detecting malignant cysts but was more sensitive than the identification of late mutations by NGS (75% vs 46%)., Conclusions: The detection of KRAS/GNAS variants improves the identification of mucinous neoplasms. Variants in TP53, SMAD4, CDKN2A, and NOTCH1 support the diagnosis of a high-risk cyst requiring surgery or additional sampling. Although molecular analysis is not a replacement for cytopathology, it does provide valuable information for accurate preoperative diagnosis, helping to classify mucinous neoplasms and high-risk cysts that require surgical resection. Cancer Cytopathol 2017;125:41-47. © 2016 American Cancer Society., (© 2016 American Cancer Society.)

Initial results by Le and colleagues, which were published in the June 25, 2015 issue of the New England Journal of Medicine, report significant responses of cancers with microsatellite instability (MSI) to anti-PD-1 inhibitors in patients who failed conventional therapy. This finding fits into a broader body of research associating somatic hypermutation and neoepitope formation with response to immunotherapy, with the added benefit of relying on a simple, widely used diagnostic test. This review surveys the pathogenesis and prognostic value of MSI, diagnostic guidelines for detecting it, and the frequency of MSI across tumors, with the goal of providing a reference for its use as a biomarker for PD-1 blockade. MSI usually arises from either germline mutations in components of the mismatch repair (MMR) machinery (MSH2, MSH6, MLH1, PMS2) in patients with Lynch syndrome or somatic hypermethylation of the MLH1 promoter. The result is a cancer with a 10- to 100-fold increase in mutations, associated in the colon with poor differentiation, an intense lymphocytic infiltrate, and a superior prognosis. Diagnostic approaches have evolved since the early 1990s, from relying exclusively on clinical criteria to incorporating pathologic features, PCR-based MSI testing, and immunohistochemistry for loss of MMR component expression. Tumor types can be grouped into categories based on the frequency of MSI, from colorectal (20%) and endometrial (22%-33%) to cervical (8%) and esophageal (7%) to skin and breast cancers (0%-2%). If initial results are validated, MSI testing could have an expanded role as a tool in the armamentarium of precision medicine., (©2016 American Association for Cancer Research.)

Cytological evaluation of pancreatic or biliary duct brushings is a specific, but insensitive, test for malignancy. We compared adjunctive molecular testing with next-generation sequencing (NGS) relative to fluorescence in situ hybridization (FISH) for detection of high-risk neoplasia or malignancy. Bile duct brushings from 81 specimens were subjected to cytological analysis, FISH using the UroVysion probe set, and targeted NGS. Specimens were placed into negative/atypical (negative) or suspicious/positive (positive) categories depending on cytology and negative or positive categories on the basis of FISH and NGS results. Performance characteristics for each diagnostic modality were calculated on the basis of clinicopathologic follow-up and compared in a receiver operating characteristic analysis. There were 33 high-risk neoplasia/malignant strictures (41%) and 48 benign (59%). NGS revealed driver mutations in 24 cases (30%), including KRAS (21 of 24 cases), TP53 (14 of 24 cases), SMAD4 (6 of 24 cases), and CDKN2A (4 of 24 cases). Cytology had a sensitivity of 67% (95% CI, 48%-82%) and a specificity of 98% (95% CI, 89%-100%). When added to cytology, NGS increased the sensitivity to 85% (95% CI, 68%-95%), leading to a significant increase in the area under the curve in a receiver operating characteristic analysis (P = 0.03). FISH increased the sensitivity to 76% (95% CI, 58%-89%), without significantly increasing the area under the curve. These results suggest that ancillary NGS testing offers advantages over FISH, although studies with larger cohorts are needed to verify these findings., (Copyright © 2016 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.)

Background: Internal tandem duplication (ITD) of the fms-related tyrosine kinase 3 (FLT3) gene is associated with a poor prognosis in acute myeloid leukemia (AML) patients with a normal karyotype. The current standard polymerase chain reaction (PCR) assay for FLT3/ITD detection is not sufficiently sensitive to monitor minimal residual disease (MRD). Clone-specific assays may have sufficient sensitivity but are not practical to implement, since each clone-specific primer/probe requires clinical validation., Objective: To develop an assay for clinical molecular diagnostics laboratories to monitor MRD in FLT3/ITD AMLs., Methods: We designed a simple novel assay, tandem duplication PCR (TD-PCR), and tested its sensitivity, specificity, and clinical utility in FLT3/ITD AML patients., Results: TD-PCR was capable of detecting a single ITD molecule and was applicable to 75 % of ITD mutants tested. TD-PCR detected MRD in bone marrow prior to patient relapse. TD-PCR also identified low-level ITD mutants not only in FLT3/ITD AMLs but also in initial diagnostic specimens that were reportedly negative by the standard assay in patients who progressed with the same ITDs detected by the TD-PCR assay., Conclusion: Detection of MRD by TD-PCR may guide patient selection for early clinical intervention. In contrast to clone-specific approaches, the TD-PCR assay can be more easily validated for MRD detection in clinical laboratories because it uses standardized primers and a universal positive control. In addition, our findings on multi-clonality and low-level ITDs suggest that further studies are warranted to elucidate their clinical/biological significance.

Background: Detection of BRAF mutations is an established standard of care to predict small-molecule inhibitor (vemurafenib) response in metastatic melanoma. Molecular assays should be designed to detect not only the most common p.V600E mutation, but also p.V600K and other non-p.V600E mutations., Objective: The purpose of this study was to assess if tumor cellularity can function as a quality assurance (QA) measure in molecular diagnostics. Potential causes of discrepancy between the observed and predicted mutant allele percentage were also explored., Methods: We correlated pathologist-generated estimates of tumor cellularity versus mutant allele percentage via pyrosequencing as a QA measure for BRAF mutation detection in formalin-fixed, paraffin-embedded melanoma specimens., Results: BRAF mutations were seen in 27/62 (44 %) specimens, with 93 % p.V600E and 7 % non-p.V600E. Correlation between p.V600E mutant percentage and tumor cellularity was poor-moderate (r = -0.02; p = 0.8), primarily because six samples showed a low p.V600E signal despite high tumor cellularity. A QA investigation revealed that our initial pyrosequencing assay showed a false positive, weak p.V600E signal in specimens with a p.V600K mutation. A redesigned assay detected BRAF mutations in 50/131 (38 %) specimens, including 30 % non-p.V600E. This revised assay showed strong correlation between p.V600E BRAF mutant percentage and tumor cellularity (r = 0.76; p ≤ 0.01). Re-evaluation of the previously discordant samples by the revised assay confirmed a high level of p.V600K mutation in five specimens., Conclusions: Pathologists play important roles in molecular diagnostics, beyond identification of correct cells for testing. Accurate evaluation of tumor cellularity not only ensures sufficient material for required analytic sensitivity, but also provides an independent QA measure of the molecular assays.

As health care organizations create larger networks, better coordination of primary and specialty care is paramount. Attention has focused on strengthening primary care by creating patient-centered medical homes. The "medical neighborhood" provides a framework for structured, reciprocal relationships that integrate specialty care and extend the principles of the medical home to all practicing physicians. The foundation of the medical neighborhood is the collaborative care agreement, which outlines mutual expectations for primary care physicians and specialists as they care for patients together. These expectations include a preconsultation exchange between the referring physician and the consultant, the consultation, and subsequent comanagement of patients over time. Although independent practices can create individualized collaborative care agreements with specific specialist colleagues, large health care provider networks and accountable care organizations should have 1 agreement for all affiliated physicians. Challenges to the medical neighborhood include fee-for-service reimbursement, existing referral relationships, and building a robust electronic platform, including a referral management module. Cooperation between physicians, regardless of their specialty, and innovation in payment models and electronic platforms will all be essential if medical neighborhoods are to succeed.

Background: The affordability of prescription medications continues to be a major public health issue in the United States. Estimates of cost-related medication underuse come largely from surveys of ambulatory patients. Hospitalized patients may be vulnerable to cost-related underuse and its consequences, but have been subject to little investigation., Objective: To determine impact of medication costs in a cohort of hospitalized managed care beneficiaries., Methods: We surveyed consecutive patients admitted to medical services at an academic medical center. Questions about cost-related underuse were based on validated measures; predictors were assessed with multivariable models. Participants were asked about strategies to improve medication affordability, and were contacted after discharge to determine if they had filled newly prescribed medications., Results: One-hundred thirty (41%) of 316 potentially eligible patients participated; 93 (75%) of these completed postdischarge surveys. Thirty patients (23%) reported cost-related underuse in the year prior to admission. In adjusted analyses, patients of black race were 3.39 times (95% confidence interval [CI], 1.05 to 11.02) more likely to report cost-related underuse than non-Hispanic white patients. Virtually all respondents (n = 123; 95%) endorsed at least 1 strategy to make medications more affordable. Few (16%) patients, prescribed medications at discharge, knew how much they would pay at the pharmacy. Almost none had spoken to their inpatient (4%) or outpatient (2%) providers about the cost of newly prescribed drugs., Conclusions: Cost-related underuse is common among hospitalized patients. Individuals of black race appear to be particularly at risk. Strategies should be developed to address this issue around the time of hospital discharge., (Copyright © 2011 Society of Hospital Medicine.)

To identify clinical predictors of last-minute preoperative cardiology consultations and to evaluate the impact of these consultations on patient care, we performed a retrospective case-control study including all 166 patients who received unscheduled cardiology consultations at the preadmission testing center (PATC) of an urban teaching hospital. Control subjects were 166 patients matched by date and category of surgical procedure. Significant (p < 0.05) independent predictors of last-minute consultations included history of myocardial infarction (odds ratio [OR] = 23.7; 95% confidence interval [CI] = 1.5 to 373), history of chest pain (OR = 15.3; 95% CI = 3.7 to 62.9), history of chronic obstructive lung disease (OR = 5.9; 95% CI = 1.1 to 32.9), prior echocardiography (OR = 3.4; 95% CI = 1.2 to 9.8), and age (OR per decade = 1.1; 95% CI = 1.04 to 1.1). Thus among patients undergoing elective noncardiac surgery, last-minute preoperative consultations are common and are usually precipitated by an abnormal electrocardiogram or history of cardiovascular disease. Last-minute consultations may be preventable if those patients with risk factors for consultation are identified in advance of the preadmission evaluation and referred for elective consultation.