ASCL1 represses a SOX9+ neural crest stem-like state in small cell lung cancer.

ASCL1 is a neuroendocrine lineage-specific oncogenic driver of small cell lung cancer (SCLC), highly expressed in a significant fraction of tumors. However, ∼25% of human SCLC are ASCL1-low and associated with low neuroendocrine fate and high MYC expression. Using genetically engineered mouse models (GEMMs), we show that alterations in Rb1/Trp53/Myc in the mouse lung induce an ASCL1+ state of SCLC in multiple cells of origin. Genetic depletion of ASCL1 in MYC-driven SCLC dramatically inhibits tumor initiation and progression to the NEUROD1+ subtype of SCLC. Surprisingly, ASCL1 loss promotes a SOX9+ mesenchymal/neural crest stem-like state and the emergence of osteosarcoma and chondroid tumors, whose propensity is impacted by cell of origin. ASCL1 is critical for expression of key lineage-related transcription factors NKX2-1, FOXA2, and INSM1 and represses genes involved in the Hippo/Wnt/Notch developmental pathways in vivo. Importantly, ASCL1 represses a SOX9/RUNX1/RUNX2 program in vivo and SOX9 expression in human SCLC cells, suggesting a conserved function for ASCL1. Together, in a MYC-driven SCLC model, ASCL1 promotes neuroendocrine fate and represses the emergence of a SOX9+ nonendodermal stem-like fate that resembles neural crest.

The Lineage-Defining Transcription Factors SOX2 and NKX2-1 Determine Lung Cancer Cell Fate and Shape the Tumor Immune Microenvironment.

The major types of non-small-cell lung cancer (NSCLC)-squamous cell carcinoma and adenocarcinoma-have distinct immune microenvironments. We developed a genetic model of squamous NSCLC on the basis of overexpression of the transcription factor Sox2, which specifies lung basal cell fate, and loss of the tumor suppressor Lkb1 (SL mice). SL tumors recapitulated gene-expression and immune-infiltrate features of human squamous NSCLC; such features included enrichment of tumor-associated neutrophils (TANs) and decreased expression of NKX2-1, a transcriptional regulator that specifies alveolar cell fate. In Kras-driven adenocarcinomas, mis-expression of Sox2 or loss of Nkx2-1 led to TAN recruitment. TAN recruitment involved SOX2-mediated production of the chemokine CXCL5. Deletion of Nkx2-1 in SL mice (SNL) revealed that NKX2-1 suppresses SOX2-driven squamous tumorigenesis by repressing adeno-to-squamous transdifferentiation. Depletion of TANs in SNL mice reduced squamous tumors, suggesting that TANs foster squamous cell fate. Thus, lineage-defining transcription factors determine the tumor immune microenvironment, which in turn might impact the nature of the tumor.

An eosinophil peroxidase activity assay accurately predicts eosinophilic chronic rhinosinusitis.

BACKGROUND: A definitive diagnosis of eosinophilic chronic rhinosinusitis (eCRS) requires invasive surgical tissue sampling and histologic enumeration of intact eosinophils. Eosinophil peroxidase (EPX) is an accurate biomarker of sinonasal tissue eosinophilia in CRS regardless of polyp status. A less invasive and rapid method that accurately identifies tissue eosinophilia would be of great benefit to patients. OBJECTIVE: We sought to evaluate a new clinical tool that uses a nasal swab and colorimetric EPX activity assay to predict a diagnosis of eCRS. METHODS: A prospective, observational cohort study was conducted using nasal swabs and sinonasal tissue biopsies obtained from patients with CRS electing endoscopic sinus surgery. Patients were classified as non-eCRS (n = 19) and eCRS (n = 35) on the basis of pathologically determined eosinophil counts of less than 10 or greater than or equal to 10 eosinophils/HPF, respectively. Swab-deposited EPX activity was measured and compared with tissue eosinophil counts, EPX levels, and CRS-specific disease metrics. RESULTS: EPX activity was significantly increased in patients with eCRS than in patients without eCRS (P < .0001). With a relative absorbance unit cutoff value of greater than or equal to 0.80, the assay demonstrated high sensitivity (85.7%) and moderate specificity (79.0%) for confirming eCRS. Spearman correlations between EPX activity and tissue eosinophil counts (rs = 0.424), EPX levels (rs = 0.503), and Lund-Kennedy endoscopy scores (rs = 0.440) in eCRS were significant (P < .05). CONCLUSIONS: This investigation evaluates a nasal swab sampling method and EPX activity assay that accurately confirms eCRS. This method could potentially address the unmet need to identify sinonasal tissue eosinophilia at the point-of-care, as well as to longitudinally monitor eosinophil activity and treatment response.

Chemokine CCL19 and Its Receptors CCR7 and CCRL1 in Chronic Rhinosinusitis.

Background: CCL19 has been shown to predict disease severity in COVID-19 and treatment response in rheumatoid arthritis. CCL19 can exert both pro- and anti-inflammatory effects and is elevated in chronic rhinosinusitis (CRS). However, its role in CRS remains unknown. This study sought to determine the transcriptional changes in CCL19, its receptors, and associated cytokines and their association with disease severity in CRS. Methods: A clinical database of control subjects and patients with CRS was examined. Lund-Kennedy, Lund-Mackay, Sinonasal Outcomes Test 22 (SNOT-22), and rhinosinusitis disability index (RSDI) scores were collected at enrollment. mRNA was extracted from sinonasal tissues and subjected to multiplex gene expression analysis. Gene transcript differences between patients with CRS and controls were compared and correlated with disease severity metrics. Immunohistochemical analyses of CCL19, CCR7, and CCRL1 were conducted to compare differences in protein expression between cohorts. A subgroup analysis was performed to compare transcriptional and protein expression difference between patients with (CRSwNP) and without (CRSsNP) nasal polyps and controls. Results: Thirty-eight subjects (control group, n=7; CRS group, n=31) were included in this study. CCRL1 (p=0.0093) and CCR7 (p=0.017) levels were significantly elevated in CRS compared to those in controls. CCL19 (p=0.038) and CCR7 (p=0.0097) levels were elevated in CRSwNP and CCRL1 was elevated in CRSsNP (p=0.0004). CCR7 expression was significantly elevated in sinonasal epithelial cells in CRSwNP (p=0.04). CCL19 expression was positively correlated with TNFA expression (p<0.0002). CCL19 and CCR7 expression was positively correlated with SNOT-22 and RSDI scores (p<0.05). Conclusion: CCL19 and CCR7 may modulate TNF-α-driven pro-inflammatory signaling and contribute to increased disease severity in CRS. Mechanistic studies are required to further elucidate the role of CCRL1 in CRS.

Rapid on-site evaluation increases endoscopic ultrasound-guided fine-needle aspiration adequacy for pancreatic lesions.

BACKGROUND: Rapid on-site evaluation (ROSE) has the potential to improve adequacy rates and affect other outcomes; however, there have been few comparative studies to assess the impact of ROSE in the setting of ultrasound-guided endoscopic fine-needle aspiration cytology for pancreatic lesions. AIMS: To determine whether ROSE improves adequacy rates of endoscopic fine-needle aspiration cytology for pancreatic lesions. METHODS: Systematic review and meta-analysis of studies reporting a head-to-head comparison of adequacy or diagnostic accuracy (with ROSE vs. without ROSE) at a single site. RESULTS: ROSE was associated with a statistically significant (p < 0.001) improvement in the adequacy rate (average 10 %, 95 % CI: 5-24 %). The impact of ROSE depends on the per-pass adequacy rate without ROSE. ROSE had no impact on diagnostic yield (p < 0.76). CONCLUSIONS: ROSE is associated with an improvement in adequacy rates when implemented at sites where the per-case adequacy rate without ROSE is low (<90 %). It is unclear whether the type of assessor (pathologist vs. non-pathologist) has a significant impact on the success rate of ROSE. ROSE has no impact on diagnostic yield. Studies should employ head-to-head comparisons of cohorts with and without ROSE at a single location.

Distinguishing Gastrointestinal Leiomyomas From Muscularis Propria in Biopsy Specimens by Differential Expression of S100 Immunohistochemical Stain.

OBJECTIVES: Interpreting small biopsy specimens or fine-needle aspirations of gastrointestinal tract (GI) smooth muscle lesions may be challenging when the differential diagnosis includes leiomyoma vs muscularis propria (MP). We evaluated the utility of S100 staining in distinguishing GI leiomyomas from MP. METHODS: A search was conducted in our laboratory information system for cases of leiomyomas arising within the GI tract (2004-2021). Site-matched controls containing MP were selected (2018-2020). Five high-power fields (hpf) were counted on S100 immunohistochemical stains by two pathologists in the resections and by three different blinded pathologists in the biopsy specimens and analyzed. RESULTS: The median S100 count was 2.5/5 hpf in leiomyoma resection cases (n = 38), which was significantly lower than the median count of 548/5 hpf in MP (n = 19) with a P value of <.0001. The median S100 count in biopsy specimens (n = 16) was 1.2/5 hpf and within the expected range of 1 to 104/5 hpf (minimum-maximum value) established by the leiomyoma resections. S100 counts in the normal MP were significantly higher than those observed in leiomyomas (P < .001). CONCLUSIONS: S100 staining can aid in distinguishing a leiomyoma from MP in the GI tract, which is especially helpful when evaluating cases with limited sampling.

Safety and Feasibility of Photodynamic Therapy for Ablation of Peripheral Lung Tumors.

BACKGROUND: Newer navigational bronchoscopy technologies render peripheral lung lesions accessible for biopsy and potential treatment. We investigated whether photodynamic therapy (PDT) delivered via navigational bronchoscopy is feasible and safe for ablation of peripheral lung tumors. METHODS: Two studies evaluated PDT in patients with solid peripheral lung tumors followed by clinical follow-up (nonresection study, N=5) or lobectomy (resection study, N=10). Porfimer sodium injection was administered 40 to 50 hours before navigational bronchoscopy. Lesion location was confirmed by radial probe endobronchial ultrasonography. An optical fiber diffuser was placed within or adjacent to the tumor under fluoroscopic guidance; laser light (630 nm wavelength) was applied at 200 J/cm of diffuser length for 500 seconds. Tumor response was assessed by modified Response Evaluation Criteria in Solid Tumors at 3 and 6 months postprocedure (nonresection study) and pathologically (resection study). RESULTS: There were no deaths, discontinuations for adverse events, or serious or grade ≥3 adverse events related to study treatments. Photosensitivity reactions occurred in 8 of 15 patients: 6 mild, 1 moderate, 1 severe (elevated porphyrins noted in blood after treatment). Among 5 patients with clinical follow-up, 1 had complete response, 3 had stable disease, and 1 had progressive disease at 6 months follow-up. Among 10 patients who underwent lobectomy, 1 had no evidence of tumor at resection (complete response), 3 had 40% to 50% tumor cell necrosis, 2 had 20% to 35%, and 4 had 5% to 10%. CONCLUSION: PDT for nonthermal ablation of peripheral lung tumors was feasible and safe in this small study. Further study is warranted to evaluate efficacy and corroborate the safety profile.

Using American Type Culture Collection Cell Lines to Evaluate Interlaboratory Variables for Estrogen Receptor and Human Epidermal Growth Factor Receptor 2 Immunostaining.

CONTEXT.­: Most laboratories currently use patient tissues for validating immunohistochemical stains. OBJECTIVE.­: To explore advantages of using cell lines with known antigenicity as a validation method. DESIGN.­: Five American Type Culture Collection (ATCC) cell lines with known negative, low positive, and moderate to strong estrogen receptor (ER) expression as well as negative, equivocal, and positive human epidermal growth factor receptor 2 (HER2) expression were cultured and made into cell blocks. One block from each cell line was fixed in formalin and another in ethanol before cell block preparation. Two sets of paired unstained slides from each block were sent to 10 different laboratories for HER2 and ER staining to be stained on runs from different days according to each laboratory's defined protocol. RESULTS.­: The 10 study participants evaluated 40 slides in a blinded fashion. For ER expression, all 80 interpretations for the ER strong and moderate positive cell lines had the target ER-positive result, and 74 of 80 ER-negative cell lines (92.5%) had agreement with the intended negative result. The ER low positive cell line showed varied but positive expression among all observers. The HER2 (3+)-positive cell lines yielded a target interpretation of 3+ in 65 of 80 interpretations (81.2%). For the HER2-negative cell line 69 of 78 interpretations (88.5%) were consistent with the target response (0 or 1+). No significant variation was observed between the ethanol- and non-ethanol-exposed cell lines, or between runs by the same laboratory. Variation from target results clustered within laboratories. CONCLUSIONS.­: This study indicates that variability between laboratories can be identified by using cell lines for quantitative or semiquantitative immunohistochemistry when using cultured cell lines of known antigenicity. These cell lines could potentially play a role in aiding anatomic pathology laboratories in validating immunohistochemistry tests for formalin- and ethanol-fixed tissues.

Decreased colorectal cancer and adenoma risk in patients with microscopic colitis.

INTRODUCTION: Microscopic colitis is currently considered to harbor no increased risk for colorectal cancer, based on a few small studies with limited long-term follow-up. Our aim was to identify patients with microscopic colitis, and to compare long-term rates of colorectal cancer or adenoma to a control group of patients without microscopic colitis. METHODS: We reviewed the records of patients diagnosed with microscopic colitis, as identified by a hospital-based pathology database from January 2000 to August 2008. Clinical factors, including history of adenoma or adenocarcinoma, and all colonoscopy findings, were recorded. Age and gender-matched patients without microscopic colitis served as the control in a 1:1 fashion. RESULTS: A total of 647 patients (153 male: 494 female) were identified with microscopic colitis (MC). Any history of colorectal cancer was detected in 1.92, 1.81, and 4.17% of patients with collagenous colitis (CC), lymphocytic colitis (LC), and controls, respectively (P = 0.095, P = 0.040, P = 0.015 for CC, LC, and all MC, respectively, comparing to controls). Overall, covariate-adjusted risk (odds ratio) of any history of colorectal cancer and colorectal adenoma in MC patients was 0.34 (95% confidence interval [CI] 0.16-0.73, P = 0.006) and 0.52 (95% CI 0.50-0.76, P < 0.0001), respectively. The mean duration of follow-up was 4.63 years, with 147/647 (22.7%) of patients with clinical follow-up >7 years. CONCLUSIONS: In this case-control study involving a large retrospective cohort, microscopic colitis is negatively associated with the risk for colorectal cancer and adenoma. Further studies are required to determine a temporal relationship between microscopic colitis and the future development of colorectal neoplasia.

Communicating Certainty in Pathology Reports.

CONTEXT.­: Pathology reports are the main modality in which results are communicated to other physicians. For various reasons, the diagnosis may be qualified on a spectrum of uncertainty. OBJECTIVE.­: To examine how communication of uncertainty is an unexamined source of possible medical error. No study to our knowledge has examined pathology reports across multiple institutions. This study seeks to identify commonly used phrases of diagnostic uncertainty and their interpreted meanings by surgical pathologists and clinicians. DESIGN.­: Anonymous surveys were completed at 3 major US academic institutions by 18 practicing staff pathologists, 12 pathology residents, 53 staff clinicians, and 50 resident/allied health professional clinicians at 5 standard tumor boards. All participants rated percentage certainty associated with 7 diagnostic terms. Pathologists answered 2 questions related to the ability to clarify a diagnosis using a comment and comfort wording pathology reports. Clinicians answered questions on how often they read a pathology report comment, if they found the comment helpful, and how comfortable they were in reading pathology reports. RESULTS.­: A wide range in percentage certainty was found for each of the 7 diagnostic phrases. Both staff and resident clinicians and residents showed wide variability in interpreting the phrases. Twenty-five of 50 staff clinicians (52%) were very comfortable reading a pathology report, whereas only 4 of 53 resident clinicians (8%) were very comfortable reading a pathology report. Twenty-four of 53 staff clinicians (63%) reported always reading the comment, yet only 20 of 53 (27%) always found the comment helpful. The phrases "diagnostic of" and "consistent with" had the strongest agreement in meaning. The weakest agreement was between "suspicious for" and "compatible with." CONCLUSIONS.­: Efforts to standardize diagnostic terms may improve communication.

Performance of specific morphologic features in distinguishing low-grade squamous intraepithelial lesions from high-grade squamous intraepithelial lesions in borderline cases: a College of American Pathologists Cytopathology Committee multiobserver study.

INTRODUCTION: Distinguishing between low-grade squamous intraepithelial lesions (LSIL) and high-grade squamous intraepithelial lesions (HSIL) can be difficult on certain Papanicolaou (Pap) tests, hindering interobserver concordance. We investigated the variables influencing the interpretation of LSIL versus HSIL in Pap test slides rejected from the College of American Pathologists PAP education program. MATERIALS AND METHODS: Eleven cytologists, who were unaware of the reference interpretation, examined 21 Pap slides (11 submitted as LSIL and 10 as HSIL) rejected from the PAP education program and recorded the number of LSIL cells, HSIL cells, keratinized dysplastic cells, LSIL clusters with mixed HSIL cells, atypical squamous metaplasia, atypical glandular cells, the presence of inflammation or infectious organisms, and the overall interpretation (LSIL or HSIL). We evaluated the significance of these 11 variables using a nonlinear mixed model analysis. RESULTS: LSIL had greater concordance (92 of 121 responses; 76.0% concordance) than HSIL (68 of 110 responses; 61.8% concordance; P < 0.001). The only predictors of misclassified cases were the number of atypical squamous metaplastic cells and the number of HSIL cells (P < 0.001). The more of these cells identified, the more likely the reviewers were to classify the slide as HSIL. The reproducibility of the diagnosis was fair (Gwet's agreement coefficient, 0.33). CONCLUSIONS: Interobserver reproducibility is a challenge for a subset of cases with features intermediate between LSIL and HSIL. Atypical squamous metaplasia and dysplastic nuclei with a nuclear/cytoplasmic ratio greater than one half of the cell volume (HSIL) present on a Pap test influenced the likelihood that a reviewer would interpret the case as HSIL rather than LSIL.

Rapid On Site Evaluation (ROSE): A Pathologists' Perspective.

Rapid on site evaluation (ROSE) has been recognized as a safeguard to help ensure adequate aspirate or biopsy sample is present for diagnostic evaluation. The method involves having a pathologist (generally a cytopathologist) on site during specimen collection to allow for feedback for the performing proceduralist. ROSE can allow for appropriate ancillary tests to be collected at the time of biopsy (eg, flow cytometry or cultures), fewer passes in the event of adequate lesional representation on initial pass(es), or adjusting the biopsy target. This article was written from the pathologists' perspective in terms of things that improve their ability to be of value on site. As you might imagine, a lot of it comes down to communication; in a sense taking advantage of the opportunity of having both the radiologist and pathologist in the same room. While not every institution has the staffing to provide ROSE, for those that do it's a good exercise to occasionally sit down and examine how to get the most out of the unique collaboration that is ROSE.

Multiple enlarging hepatic and retroperitoneal myelolipomas in the setting of Cushing disease.

Myelolipomas are benign tumours typically occurring in the adrenal glands, made up of fat and trilineage haematopoeitic cells resembling bone marrow. Their aetiology is not well understood; however, they have a clear association with elevated serum adrenocorticotropic hormone (ACTH). Extra-adrenal myelolipomas are rare, and to our knowledge there are no previously reported cases of multiple enlarging hepatic and retroperitoneal myelolipomas in the setting of Cushing disease. We present the case of a patient with an ACTH-producing pituitary adenoma who developed multiple enlarging fat containing lesions in the liver and retroperitoneum, which were histologically proven multifocal myelolipomas.

Core needle biopsy with endobronchial ultrasonography: single center experience with 100 cases.

INTRODUCTION: Adequate sampling by endobronchial ultrasound (EBUS)-transbronchial needle aspiration to meet the demands of precision medicine or histologic evaluation is challenging. There is increasing demand for core biopsy specimens with advances in therapy. Franseen enodoscopic ultrasound needles have shown promising results in gastroenterology application for obtaining core biopsies and same design has recently been extended for pulmonary use. We evaluated Franseen needles with EBUS to assess its utility, safety and ability to provide core biopsy specimens. MATERIALS AND METHODS: Retrospective analysis of our database at the University of Utah of patients undergoing EBUS with a Franseen needle was performed to ascertain the performance characteristics of this needle in the first 100 patients after its implementation. Medical records were also reviewed to identify any immediate procedure-related complications. RESULTS: One hundred seventy locations were sampled in 100 patients. A total of 152 lymph nodes and 18 masses were sampled. Core biopsies, as per pathology report, were seen in 87% of patients. A clinically concordant pathological diagnosis was established in 97% of patients. Diagnostic yield for granulomatous lymphadenopathy was 95.6% (22 of 23). No patient-related adverse events were noted. CONCLUSION: The Franseen needle evaluated in this study can safely procure core tissue samples during EBUS bronchoscopy that are adequate for histopathological diagnosis in benign and malignant lesions. Its ability to provide adequate tissue in patients with granulomatous inflammation is encouraging.

Comparison of EUS-guided conventional smear and liquid-based cytology in pancreatic lesions: A systematic review and meta-analysis.

Background and study aims Endoscopic ultrasound (EUS)-guided fine-needle aspiration (EUS-FNA) has limitations of inadequate sampling and false-negative results for malignancy. It has been performed using conventional smear (CS) cytology with rapid on-site evaluation (ROSE) with reasonable diagnostic accuracy. An alternative to ROSE is liquid-based cytology (LBC). Commonly used LBC techniques include precipitation-based (SurePath™) and filtration-based (ThinPrep ® , CellPrep ® ). Data regarding the diagnostic efficacy of LBC compared with CS are limited. Methods Multiple databases were searched through March 2020 to identify studies reporting diagnostic yield of EUS-guided CS and LBC in pancreatic lesions. Pooled diagnostic odds and rates of performance for the cytologic diagnoses of benign, suspicious, and malignant lesions were calculated. Diagnostic efficacy was evaluated by pooled rates of accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). Results Nine studies with a total of 1308 patients were included in our final analysis. Pooled diagnostic odds of CS cytology were 1.69 (CI 1.02-2.79) and 0.39 (CI 0.19-0.8) for malignant lesions when compared to filtration-based and precipitation-based LBC techniques, respectively. For CS, precipitation-based and filtration-based LBC, pooled diagnostic accuracy was 79.7 %, 85.2 %, 77.3 %, sensitivity was 79.2 %, 83.6 %, 68.3 %, and specificity was 99.4 %, 99.5 %, 99.5 %, respectively. Conclusions The precipitation-based LBC technique (SurePath™) had superior diagnostic odds for malignant pancreatic lesions compared with CS cytology in the absence of ROSE. It showed superior accuracy and sensitivity, but comparable specificity and PPV. Diagnostic odds of CS cytology in the absence of ROSE were superior to the filtration-based LBC technique (ThinPrep ® , Cellprep ® ) for diagnosing malignant pancreatic lesions.

MYC Drives Temporal Evolution of Small Cell Lung Cancer Subtypes by Reprogramming Neuroendocrine Fate.

Small cell lung cancer (SCLC) is a neuroendocrine tumor treated clinically as a single disease with poor outcomes. Distinct SCLC molecular subtypes have been defined based on expression of ASCL1, NEUROD1, POU2F3, or YAP1. Here, we use mouse and human models with a time-series single-cell transcriptome analysis to reveal that MYC drives dynamic evolution of SCLC subtypes. In neuroendocrine cells, MYC activates Notch to dedifferentiate tumor cells, promoting a temporal shift in SCLC from ASCL1+ to NEUROD1+ to YAP1+ states. MYC alternatively promotes POU2F3+ tumors from a distinct cell type. Human SCLC exhibits intratumoral subtype heterogeneity, suggesting that this dynamic evolution occurs in patient tumors. These findings suggest that genetics, cell of origin, and tumor cell plasticity determine SCLC subtype.

Prediction of survival of HPV16-negative, p16-negative oral cavity cancer patients using a 13-gene signature: A multicenter study using FFPE samples.

OBJECTIVES: To test the performance of an oral cancer prognostic 13-gene signature for the prediction of survival of patients diagnosed with HPV-negative and p16-negative oral cavity cancer. MATERIALS AND METHODS: Diagnostic formalin-fixed paraffin-embedded oral cavity cancer tumor samples were obtained from the Fred Hutchinson Cancer Research Center/University of Washington, University of Calgary, University of Michigan, University of Utah, and seven ARCAGE study centers coordinated by the International Agency of Research on Cancer. RNA from 638 Human Papillomavirus (HPV)-negative and p16-negative samples was analyzed for the 13 genes using a NanoString assay. Ridge-penalized Cox regressions were applied to samples randomly split into discovery and validation sets to build models and evaluate the performance of the 13-gene signature in predicting 2-year oral cavity cancer-specific survival overall and separately for patients with early and late stage disease. RESULTS: Among AJCC stage I/II patients, including the 13-gene signature in the model resulted in substantial improvement in the prediction of 2-year oral cavity cancer-specific survival. For models containing age and sex with and without the 13-gene signature score, the areas under the Receiver Operating Characteristic Curve (AUC) and partial AUC were 0.700 vs. 0.537 (p < 0.001), and 0.046 vs. 0.018 (p < 0.001), respectively. Improvement in predicting prognosis for AJCC stage III/IV disease also was observed, but to a lesser extent. CONCLUSIONS: If confirmed using tumor samples from a larger number of early stage oral cavity cancer patients, the 13-gene signature may inform personalized treatment of early stage HPV-negative and p16-negative oral cavity cancer patients.

Characterization of PD-L1 Immunohistochemical Expression in Cell Blocks With Different Specimen Fixation and Processing Methods.

Interpretative criteria for programmed death-ligand 1 (PD-L1) immunohistochemistry (IHC) have been largely based on data from formalin-fixed, paraffin-embedded tissues, despite the fact that cytologic specimens, especially cell blocks, are often the only or most readily available tissue for testing. Unlike biopsy specimens, however, cytology sample processing methods can vary markedly. The purpose of this study was to evaluate the effects of several common preanalytic variables on PD-L1 IHC. Two cell lines with strong expression of PD-L1 (H441) and no expression (MCF7) were cultured in vitro. Harvested cells were collected in PreservCyt, CytoLyt, cell culture media (RPMI), saline, and formalin. Cell blocks were prepared by the plasma-thromboplastin method or Cellient automated system and stained with the FDA-approved 28-8 PD-L1 antibody per protocol. PD-L1 expression was scored manually by 3 pathologists for stain intensity and localization and compared across preparation methods. Several IHC staining patterns were observed: complete membranous, partial membranous, globular, and cytoplasmic, with some overlap. Cellient blocks had the best interobserver agreement and cytomorphology, highest proportion of strong complete membranous staining (82%), and least amount of cytoplasmic (11%) and globular staining (8%). RPMI, saline, and formalin samples demonstrated increased amounts of cytoplasmic and globular staining relative to Cellient, while CytoLyt exhibited the poorest performance overall. Interpretation of PD-L1 IHC on cell blocks is feasible for most processing methods examined, but may require recognition of increased cytoplasmic and globular staining in some sample types. Cellient cell blocks demonstrated superior performance compared with other methods.

Low-Grade Squamous Intraepithelial Lesion or High-Grade Squamous Intraepithelial Lesion? Concordance Between the Interpretation of Low-Grade Squamous Intraepithelial Lesion and High-Grade Squamous Intraepithelial Lesion in Papanicolaou Tests: Results From the College of American Pathologists PAP Education Program.

CONTEXT.­: Obtaining diagnostic concordance for squamous intraepithelial lesions in cytology can be challenging. OBJECTIVE.­: To determine diagnostic concordance for biopsy-proven low-grade squamous intraepithelial lesion (LSIL) and high-grade squamous intraepithelial lesion (HSIL) Papanicolaou test slides in the College of American Pathologists PAP Education program. DESIGN.­: We analyzed 121 059 responses from 4251 LSIL and HSIL slides for the interval 2004 to 2013 using a nonlinear mixed-model fit for reference diagnosis, preparation type, and participant type. We evaluated interactions between the reference diagnosis and the other 2 factors in addition to a repeated-measures component to adjust for slide-specific performance. RESULTS.­: There was a statistically significant difference between misclassification of LSIL (2.4%; 1384 of 57 664) and HSIL (4.4%; 2762 of 63 395). There was no performance difference between pathologists and cytotechnologists for LSIL, but cytotechnologists had a significantly higher HSIL misclassification rate than pathologists (5.5%; 1437 of 27 534 versus 4.0%; 1032 of 25 630; P = .01), and both were more likely to misrepresent HSIL as LSIL ( P < .001) than the reverse. ThinPrep LSIL slides were more likely to be misclassified as HSIL (2.4%; 920 of 38 582) than SurePath LSIL slides (1.5%; 198 of 13 196), but conventional slides were the most likely to be misclassified in both categories (4.5%; 266 of 5886 for LSIL, and 6.5%; 573 of 8825 for HSIL). CONCLUSIONS.­: More participants undercalled HSIL as LSIL (false-negative) than overcalled LSIL as HSIL (false-positive) in the PAP Education program, with conventional slides more likely to be misclassified than ThinPrep or SurePath slides. Pathologists and cytotechnologists classify LSIL equally well, but cytotechnologists are significantly more likely to undercall HSIL as LSIL than are pathologists.

An Update on the Risk of Lymph Node Metastasis for the Follicular Variant of Papillary Thyroid Carcinoma with the New Diagnostic Paradigm.

Previous data has shown that the risk of nodal metastases is significantly greater for classical papillary thyroid carcinoma (PTC) as compared to the follicular variant (FVPTC). Given a recent change in diagnostic paradigm and definition of the noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) we intended to investigate if there remains a significant difference in nodal involvement between classical PTC and FVPTC. A 6-year retrospective review of all cases with FVPTC in the diagnostic line from the University of Utah/ARUP Laboratories was conducted. Two pathologists reviewed the remaining cases using the recently described histologic criteria of NIFTP to determine the total number the FVPTCs fitting the new classification paradigm. Histologic and clinical follow-up was tracked for all patients to determine the rate of nodal disease for all groups. 127 cases were identified using the above listed criteria. Forty-seven cases (37%) were classified as NIFTPs. None of the 47 patients had nodal disease either at the time of surgery or on follow-up. Twenty-eight cases met the current criteria for FVPTC (21%); of these 7/28 (25%) had evidence of nodal disease. By comparison, 17/45 (38%) of patients with mixed classical and FVPTC had nodal disease. Overall, there was no statistically significant difference in the risk of nodal metastasis between the pure FVPTC and mixed classical/FVPTC groups (p = 0.43). Our data indicates that implementing new definition for FVPTC will narrow the gap in the risk of nodal metastases between the classical PTC and FVPTC histologic subtypes.