Clinicopathologic Features of Gastrointestinal Tract Langerhans Cell Histiocytosis.

Gastrointestinal (GI) tract involvement by Langerhans cell histiocytosis (LCH) is rare and its clinicopathologic characteristics have only been described in case reports and small series. We reviewed hematoxylin and eosin and CD1a, S100, and Langerin immunohistochemical-stained slides from 47 patients with well-documented demographic and clinical findings. Our cases included 8 children and 39 adults, with a mean follow-up of 63 months. All pediatric patients had concurrent multisystem LCH, presented with GI symptoms, and showed nonpolypoid lesions. Seven (88%) showed multifocal GI disease, including 5 with multiple GI organ involvement. All sampled lesions from children exhibited infiltrative growth. More than half had died of the disease or manifested persistent LCH at last follow-up. Twenty-five of 39 (64%) adults had LCH involving only the GI tract (single system), with the remaining 14 (36%) exhibiting multisystem disease. Adult single-system GI LCH was typically encountered incidentally on screening/surveillance endoscopy (72%). Most exhibited isolated colorectal involvement (88%) as a solitary polyp (92%), with a well-demarcated/noninfiltrative growth pattern (70%), and excellent prognosis (100%). In comparison, adult patients with multisystem LCH more frequently presented with GI symptoms (92%, P < .001), noncolorectal GI site involvement (50%, P = .02), multifocal GI lesions (43%, P = .005), nonpolypoid lesions (71%, P < .001), infiltrative histologic growth pattern (78%, P = .04), and persistent disease (57%, P < .001). Adult patients with multisystem LCH appear to exhibit similar clinicopathologic features to those of pediatric patients. These results demonstrated that adults with single-system LCH involving the GI tract have an excellent prognosis, whereas multisystem LCH occurring at any age carries an unfavorable prognosis. High-risk features of GI LCH include pediatric age, GI symptomatology, noncolorectal GI involvement, multifocal GI disease, nonpolypoid lesions, and infiltrative growth pattern.

Nuclear DUX4 immunohistochemistry is a highly sensitive and specific marker for the presence of CIC::DUX4 fusion in CIC-rearranged sarcomas: a study of 48 molecularly confirmed cases.

AIMS: CIC-rearranged sarcomas (CRS) are clinically aggressive undifferentiated round cell sarcomas (URCS), commonly driven by CIC::DUX4. Due to the repetitive nature of DUX4 and the variability of the fusion breakpoints, CIC::DUX4 fusion may be missed by molecular testing. Immunohistochemical (IHC) stains have been studied as surrogates for the CIC::DUX4 fusion. We aim to assess the performance of DUX4 IHC in the work-up of CRS and its expression in non-CRS round cell or epithelioid neoplasms. METHODS AND RESULTS: Cases of molecularly confirmed CRS (n = 48) and non-CRS (n = 105) were included. CRS cases consisted of 35 females and 13 males, with ages ranging from less than 1 year to 67 years (median = 41 years). Among the molecularly confirmed non-CRS cases, C-terminal DUX4 expression was investigated in Ewing sarcomas (38 cases), alveolar rhabdomyosarcomas (18 cases), desmoplastic small round cell tumours (12 cases) and synovial sarcomas (n = five), as well as in non-mesenchymal neoplasms such as SMARCA4/SMARCB1-deficient tumours (n = five), carcinomas of unknown primary (n = three) and haematolymphoid neoplasms (four cases). DUX4 IHC was considered positive when strong nuclear expression was detected in more than 50% of neoplastic cells. When used as a surrogate for the diagnosis of CRS, the sensitivity and specificity of DUX4 IHC was 98 and 100%, respectively. Only one CRS case was negative for DUX4 IHC and harboured a CIC::FOXO4 fusion. CONCLUSIONS: DUX4 IHC is a highly sensitive and specific surrogate marker for the presence of CIC::DUX4 fusion, demonstrating its utility in establishing a diagnosis of CRS.

Superficial low-grade fibromyxoid sarcoma.

BACKGROUND: Low-grade fibromyxoid sarcoma (LGFMS) typically involves deep soft tissue (beneath the fascia) of the proximal extremities and trunk. Long-term follow-up has shown a high rate of local recurrence, metastasis, and death. To the best of our knowledge, there is only one previous large series focusing on superficial LGFMS suggesting superficial tumors are disproportionately more common in children and may have a better prognosis. Our study's primary goals are to confirm these findings and increase general awareness that LGFMS may arise in superficial soft tissue. METHODS: We retrieved our cases of superficial LGFMS diagnosed between 2008 and 2020. Available slides were reviewed, and clinical data and follow-up information were obtained. RESULTS: The patients included nine males and 14 females with a median age of 29 years; eight (35%) were children (<18 years) and five (22%) were young adults (18-30 years). The majority involved the lower extremities (65%). The tumors were primarily centered in the subcutis (91%) and dermis (9%). Microscopically, they had typical features of LGFMS with alternating fibrous and myxoid zones composed of bland, slightly hyperchromatic spindled cells. All were positive for MUC4 by immunohistochemistry and/or FUS rearrangement by FISH. Follow-up on 14 cases ranged from 11 to 148 months (median 61 months) with no evidence of recurrences or distant metastases. CONCLUSIONS: Compared to conventional deep-seated counterparts, superficial LGFMS is more likely to occur in the extremities of children and young adults and may have a better clinical outcome. Further studies with longer follow-up will likely help support these findings.

Wide-area transepithelial sampling for dysplasia detection in Barrett's esophagus: a systematic review and meta-analysis.

BACKGROUND AND AIMS: Seattle protocol forceps biopsy sampling (FB) is currently recommended for surveillance in Barrett's esophagus (BE) but limited by sampling error and lack of compliance. Wide-area transepithelial sampling with 3-dimensional analysis (WATS3D; CDx Diagnostics, Suffern, NY, USA) is reported to increase BE dysplasia detection. We assessed the incremental yield and clinical significance of WATS3D for dysplasia detection over FB in a systematic review and meta-analysis. METHODS: We queried major scientific databases for studies using WATS3D and FB from 2000 to 2020. The primary outcome was the incremental yield of WATS3D-detected dysplasia (defined as a composite of indefinite for dysplasia, low- and high-grade dysplasia [HGD] and esophageal adenocarcinoma [EAC]) over FB. Secondary outcomes were incremental yields of HGD/EAC and rate of reconfirmation of WATS3D dysplasia on subsequent FB. RESULTS: Meta-analysis of 7 eligible studies demonstrated that FB diagnosed dysplasia in 15.9% of cases, whereas the incremental yield with WATS3D was 7.2% (95% confidence interval, 3.9%-11.5%; I2= 92.1%). Meta-analysis of 6 studies demonstrated that FB diagnosed HGD/EAC in 2.3% of patients, whereas the incremental yield with WATS3D was 2.1% (95% confidence interval, .4%-5.3%; I2= 92.7%). Notably, WATS3D was negative in 62.5% of cases where FB identified dysplasia. Two studies reported reconfirmation of WATS3D dysplasia with FB histology in only 20 patients. CONCLUSIONS: WATS3D increases dysplasia detection; however, the clinical significance of this increased dysplasia detection remains uncertain. Data from endoscopic follow-up to ascertain FB histology in patients with dysplasia based solely on WATS3D are needed to determine the optimal clinical application and significance of WATS3D-only dysplasia.

Superficial ALK-rearranged myxoid spindle cell neoplasm: a cutaneous soft tissue tumor with distinctive morphology and immunophenotypic profile.

Gene rearrangements involving the anaplastic lymphoma kinase (ALK) receptor tyrosine kinase gene have been identified in various neoplasms, including inflammatory myofibroblastic tumor and epithelioid fibrous histiocytoma. We present an ALK-rearranged cutaneous soft tissue tumor with unique morphologic and immunophenotypic features that are not shared by other entities with ALK rearrangements. The six cases involved two females and four males, aged 18-84 (mean 51) years old. Three tumors were on the back and three on the lower extremities (thigh, knee, shin); ranging from 0.5 to 5.6 (mean 2.1) cm. Four were confined to the dermis; two involved the subcutis. All six cases were characterized by the presence of spindled to ovoid cells arranged in concentric whorls and cords against a myxoid to myxohyaline stroma and relatively cellular aggregates of plump ovoid to epithelioid cells. Four cases showed distinct hyalinized blood vessels. Both cases that involved the subcutis showed peripheral lipofibromatosis-like areas. Tumor-infiltrating lymphocytes were absent to moderate. Severe cytologic atypia or conspicuous mitotic activity was not identified. Immunohistochemically, all tumors diffusely expressed ALK (D5F3) and CD34. All but one tumor was diffusely positive for S100 protein. All tumors were negative for EMA, AE1/AE3, SMA, and SOX10. Next-generation sequencing revealed ALK fusions with FLNA (3 cases), MYH10 (2 cases), and HMBOX1 (1 case) as the partner genes. In all six cases, the breakpoints involved exon 20 of ALK, which preserves the receptor tyrosine kinase domains of ALK in the fusion product. Of the four cases with limited follow-up information (2-18 months), none recurred. In conclusion, we report an ALK-rearranged cutaneous soft tissue tumor characterized by the presence of myxoid spindle cell whorls and cords, and co-expression of ALK, CD34, and frequently S100 protein, we term "superficial ALK-rearranged myxoid spindle cell neoplasm".

Non-conventional dysplasias of the tubular gut: a review and illustration of their histomorphological spectrum.

The increasing use of gastrointestinal endoscopic procedures has led to the recognition by histopathologists of non-conventional (or special-type) dysplasias of the gastrointestinal tract. These lesions can be recognised in association with prevalent underlying gastrointestinal conditions, such as Barrett oesophagus, chronic atrophic gastritis, and inflammatory bowel disease. The diagnosis of these special types can be challenging, and their biological behaviours are not fully characterised. The aim of this review is to provide a global view of non-conventional dysplastic lesions observed in the various segments of the tubular gastrointestinal tract and describe their salient features. Furthermore, as the clinical implications of these various subtypes have not been broadly tested in practice and are not represented in most management guidelines, we offer guidance on the best management practices for these lesions.

Allaying uncertainty in diagnosing buried Barrett's esophagus.

Subsquamous intestinal metaplasia (SSIM) in the setting of Barrett's esophagus (BE) is a technically challenging diagnosis. While the risk for progression of BE involving the surface mucosa is well documented, the potential risk for development of advanced neoplasia associated with SSIM has been controversial. This study aimed to determine the effects of specimen adequacy, presence of dysplasia, and interobserver agreement for SSIM interpretation. Adult patients (n = 28) who underwent endoscopic therapy for BE with high-grade dysplasia or intramucosal carcinoma (HGD/IMC) between October 2005 and June 2013 were included. Initial evaluation (n = 140 slides) by an experienced gastrointestinal pathologist was followed by an interobserver study by 8 pathologists. Forty-seven (34%) slides had insufficient subsquamous tissue to assess for SSIM. SSIM was found in 19% of all slides and 29% of slides with sufficient subsquamous tissue. At least one slide had SSIM in 54% to 64% of patients. Subsquamous low grade dysplasia (LGD) was found in 4 (15%) slides with SSIM and subsquamous HGD/IMC was found in 5 (19%) slides with SSIM. At the patient level, 8 (53%) had no dysplasia, 4 (27%) had LGD and 3 (20%) had HGD/IMC. Overall agreement for SSIM by slide was 92% to 94% (κ = 0.73 to κ = 0.82, moderate to strong agreement), and by patient was 82% to 94% (κ = 0.65 to κ = 0.87, moderate to strong agreement). This study confirms the need for assessing specimen adequacy and assessing the prevalence of SSIM and is the first to assess interobserver agreement for SSIM and dysplasia within SSIM.

Myxoinflammatory fibroblastic sarcoma: an immunohistochemical and molecular genetic study of 73 cases.

Myxoinflammatory fibroblastic sarcoma (MIFS) is a rare, low-grade soft tissue neoplasm preferentially arising in the extremities of young to middle-aged adults characterized histologically by a variegated appearance and absence of a distinctive immunophenotype. Herein we have evaluated a series of 73 cases of MIFS to define potential features and markers that may facilitate diagnosis. An immunohistochemical study with a large panel of antibodies showed strong positivity of the tumor cells for bcl-1 (94.5%), FXIIIa (89%), CD10 (80%), and D2-40 (56%). FISH and array comparative genomic hybridization (aCGH) were performed in a large subset of cases to investigate the utility for detecting the TGFBR3 and OGA t(1;10) rearrangement and BRAF abnormalities. Using a combination of FISH and/or aCGH, t(1;10) was detected in only 3 of 54 cases (5.5%). The aCGH study also demonstrated amplification of VGLL3 on chromosome 3 that was detected in 8 of 20 cases (40%). BRAF alterations were observed by FISH in 4 of 70 cases (5.7%) and correlated with gain of chromosome 3p12 (VGLL3). A novel fusion transcript involving exon 6 of ZNF335 and exon 10 of BRAF was identified in one case. Demonstration of amplification of VGLL3 on chromosome 3 in combination with expression of bcl-1 and FXIIIa may help support the diagnosis, however, due to their low specificity these markers are not sufficient for a definitive diagnosis in the absence of the appropriate clinical-pathological context. Until a more robust genetic or immunohistochemical signature is identified, the diagnosis of MIFS rests on its characteristic clinicopathological features.

Smooth muscle tumors of the gastrointestinal tract: an analysis of prognostic features in 407 cases.

Smooth muscle tumors represent the second most common mural mesenchymal neoplasm in the gastrointestinal tract, but established criteria for prognostic assessment of these tumors are lacking. A large cohort of surgically resected intramural gastrointestinal smooth muscle tumors from 31 institutions was analyzed to identify potential prognostic features. Pathologic features were assessed by expert gastrointestinal and/or soft tissue pathologists at each center. Immunohistochemical confirmation was required. A total of 407 cases from the esophagus (n = 97, 24%), stomach (n = 180, 44%), small bowel (n = 74, 18%), and colorectum (n = 56, 14%) were identified. Patients ranged in age from 19 to 92 years (mean 55 years), with a slight female predominance (57%). Mean tumor size was 5.4 cm, with the largest tumor measuring 29 cm. Disease progression following surgery, defined as local recurrence, metastasis, or disease-related death, occurred in 56 patients (14%). Colorectal tumors were most likely to progress, followed by small bowel and gastric tumors. None of the esophageal tumors in this series progressed. Receiver operator characteristic analysis identified optimal cutoffs of 9.8 cm and 3 mitoses/5 mm2 for discriminating between progressive and non-progressive tumors. Histologic features strongly associated with progression by univariate analysis included moderate-to-severe atypia, high cellularity, abnormal differentiation (defined as differentiation not closely resembling that of normal smooth muscle), tumor necrosis, mucosal ulceration, lamina propria involvement, and serosal involvement (P < 0.0001 for all features). Age, sex, and margin status were not significantly associated with progression (P = 0.23, 0.82, and 0.07, respectively). A risk assessment table was created based on tumor site, size, and mitotic count, and Kaplan-Meier plots of progression-free survival for each subgroup revealed progression-based tiers. Based on our findings, it appears that nonesophageal gastrointestinal smooth muscle tumors measuring >10 cm and/or showing ≥3 mitoses/5 mm2 may behave aggressively, and therefore close clinical follow-up is recommended in these cases.

Gastrointestinal tissue-based molecular biomarkers: a practical categorisation based on the 2019 World Health Organization classification of epithelial digestive tumours.

Molecular biomarkers have come to constitute one of the cornerstones of oncological pathology. The method of classification not only directly affects the manner in which patients are diagnosed and treated, but also guides the development of drugs and of artificial intelligence tools. The aim of this article is to organise and update gastrointestinal molecular biomarkers in order to produce an easy-to-use guide for routine diagnostics. For this purpose, we have extracted and reorganised the molecular information on epithelial neoplasms included in the 2019 World Health Organization classification of tumours. Digestive system tumours, 5th edn.

Clinical Outcomes Based on the Timing of Appearance of Visible Lesions in Barrett's Esophagus During Endoscopic Eradication Therapy.

BACKGROUND AND GOALS: Visible lesions (VLs) in Barrett's esophagus (BE) are seen in 70% to 90% of patients presenting for endoscopic eradication therapy (EET). It is not known if there are any differences in outcomes of patients with flat dysplasia versus patients with VL. Our aim was to assess outcomes of EET in BE patients with VL and BE patients with flat dysplasia. STUDY: This is a single center study with data drawn from a prospective registry of patients referred for EET of BE between 2011 and 2015. Demographic data, endoscopic findings, histologic findings, and response to EET were analyzed. RESULTS: There were 264 patients of which 34 had flat dysplasia, 180 had VL before initiating EET (prevalent lesions) and 50 who developed VL during EET (incident lesions). Compared with patients with flat dysplasia, patients with VL had longer segments of BE (5 vs. 4 cm, P=0.002) and greater prevalence of high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC) (63.6% vs. 29.4%, P<0.001). Incident lesions are less likely to harbor HGD/EAC compared with prevalent lesions (28.1% vs. 61.8%, P<0.001). There were no significant differences in eradication of metaplasia/dysplasia between the groups. No progression or recurrences were observed in flat dysplasia group. In VL group, 14 patients progressed (prevalent VL=11, incident VL=3) and 15 had recurrences (prevalent VL=11, incident VL=4). CONCLUSIONS: About 19% of BE patients developed VL during EET. There is higher prevalence of HGD/EAC in prevalent VL compared with incident VL. However, the outcomes did not differ.

DNA flow cytometric and interobserver study of crypt cell atypia in inflammatory bowel disease.

AIMS: The pathological features and diagnostic reliability of crypt cell atypia (CCA) arising in inflammatory bowel disease (IBD) and its clinical significance are unknown. METHODS AND RESULTS: DNA flow cytometry (FCM) was performed on 14 colon biopsies of CCA from seven IBD patients (male-to-female ratio, 5:2; mean age, 53 years; mean IBD duration, 15 years) using paraffin-embedded tissue. Seven gastrointestinal pathologists were asked to diagnose each biopsy as negative for dysplasia (NEG), indefinite for dysplasia (IND), low-grade dysplasia (LGD) or high-grade dysplasia (HGD) by morphology alone, then again with knowledge of FCM results. Aneuploidy was detected in all 14 biopsies, and five of eight biopsies (63%) also showed strong and diffuse nuclear staining for p53 in the areas of CCA. Six (86%) patients developed HGD (n = 5) or adenocarcinoma (n = 1) in the same colonic segment where CCA had been diagnosed within a mean follow-up time of 27 months. No follow-up information was available in the remaining one patient. When diagnoses were grouped as NEG or 'atypical' (including IND, LGD or HGD), the overall agreement rate of 76% (kappa = 0.51) based on morphology alone improved to 90% (kappa = 0.81) with knowledge of FCM results. Even when categorised as NEG or dysplasia (LGD or HGD) with each of the IND diagnoses reclassified into three categories (NEG, LGD or HGD) based on the degree of suspicion for dysplasia, the overall agreement rate of 63% (kappa = 0.25) based on morphology alone improved to 73% (kappa = 0.46) with knowledge of FCM results. However, when grouped as NEG, LGD or HGD, the overall agreement rate was less than 40% (kappa < 0.09) regardless of knowledge of FCM results. CONCLUSIONS: The presence of aneuploidy, p53 positivity and development of HGD or adenocarcinoma on follow-up indicate that CCA likely represents a dysplastic lesion (at least LGD) and is a histological marker of neoplastic progression. Although the grading of CCA, largely based on cytological abnormalities, is subject to significant interobserver variability, CCA can be histologically identified and should lead to a recommendation of increased endoscopic surveillance, especially if aneuploidy is detected.

Discordance Among Pathologists in the United States and Europe in Diagnosis of Low-Grade Dysplasia for Patients With Barrett's Esophagus.

BACKGROUND & AIMS: There is suboptimal inter-observer agreement, even among expert gastrointestinal pathologists, in the diagnosis of low-grade dysplasia (LGD) in patients with Barrett's esophagus (BE). We analyzed histopathologic criteria required for a diagnosis of LGD using the new subcategories of LGD with inflammatory and dysplastic features. We categorized each diagnosis based on the level of confidence and assessed inter-observer agreement among gastrointestinal pathologists from 5 tertiary centers in the United States and Europe. METHODS: In the first phase of the study, 3 pathologists held a consensus conference at which they discussed the diagnostic criteria for LGD. In the second phase, 79 slides from patients with BE (23 samples of non-dysplastic BE, 22 samples of LGD, and 34 samples of high-grade dysplasia) were identified, randomly assigned to 7 pathologists (4 from the United States and 3 from Europe), and interpreted in a blinded fashion. κ Values were calculated for inter-observer agreement. We performed multinomial logistic regression analysis to assess the weighting of histologic features with the diagnosis. RESULTS: The overall κ value for diagnosis was 0.43 (95% confidence interval [CI], 0.42-0.48). When categorized based on degree of dysplasia, the κ value was 0.22 (95% CI, 0.11-0.29) for non-dysplastic BE, 0.11 (95% CI, 0.004-0.15) for LGD, and 0.43 (95% CI, 0.36-0.46) for high-grade dysplasia. When all pathologists made a diagnosis with high confidence, the inter-observer agreement was substantial among the US pathologists (κ, 0.63; 95% CI, 0.61-0.66) and European pathologists (κ, 0.80; 95% CI, 0.74-0.97). The κ values for all diagnoses made by European pathologists were higher than those made by US pathologists. CONCLUSIONS: In an analysis of criteria used in histopathologic diagnosis of LGD, we did not observe improvement in level of agreement among experienced pathologists, even after accounting for inflammation. The level of inter-observer agreement increased with level of pathologist confidence. There was also a difference in reading of histopathology samples of BE tissues between US and European pathologists.

Increased detection of Barrett's esophagus-associated neoplasia using wide-area trans-epithelial sampling: a multicenter, prospective, randomized trial.

BACKGROUND AND AIMS: Wide-area transepithelial sampling (WATS) with computer-assisted 3-dimensional analysis is a sampling technique that combines abrasive brushing of the Barrett's esophagus (BE) mucosa followed by neural network analysis to highlight abnormal-appearing cells. METHODS: We performed a randomized trial of referred BE patients undergoing surveillance at 16 medical centers. Subjects received either biopsy sampling followed by WATS or WATS followed by biopsy sampling. The primary outcome was rate of detection of high-grade dysplasia/esophageal adenocarcinoma (HGD/EAC) using WATS in conjunction with biopsy sampling compared with biopsy sampling alone using standard histopathologic criteria. Secondary aims included evaluating neoplasia detection rates based on the procedure order (WATS vs biopsy sampling first), of each procedure separately, and the additional time required for WATS. RESULTS: One hundred sixty patients (mean age, 63.4 years; 76% men; 95% white) completed the trial. The median circumferential and maximal BE extents were 1.0 cm (interquartile range: .0-5.0) and 4.0 cm (interquartile range, 2.0-8.0), respectively. The diagnostic yield for biopsy sampling alone was as follows: HGD/EAC, 7 (4.4%); low-grade dysplasia (LGD), 28 (17.5%); nondysplastic BE (NDBE), 106 (66.25%); and no BE, 19 (11.9%). The addition of WATS to biopsy sampling yielded an additional 23 cases of HGD/EAC (absolute increase, 14.4%; 95% confidence interval, 7.5%-21.2%). Among these 23 patients, 11 were classified by biopsy sampling as NDBE and 12 as LGD/indefinite for dysplasia (IND); 14 received biopsy sampling first and 9 WATS first (not significant) and most (n = 21; 91.7%) had a prior dysplasia history. WATS added an average of 4.5 minutes to the procedure. CONCLUSION: Results of this multicenter, prospective, randomized trial demonstrate that the use of WATS in a referral BE population increases the detection of HGD/EAC. (Clinical trial registration number: NCT03008980.).

Development and Validation of a Classification System to Identify High-Grade Dysplasia and Esophageal Adenocarcinoma in Barrett's Esophagus Using Narrow-Band Imaging.

BACKGROUND & AIMS: Although several classification systems have been proposed for characterization of Barrett's esophagus (BE) surface patterns based on narrow-band imaging (NBI), none have been widely accepted. The Barrett's International NBI Group (BING) aimed to develop and validate an NBI classification system for identification of dysplasia and cancer in patients with BE. METHODS: The BING working group, composed of NBI experts from the United States, Europe, and Japan, met to develop a validated, consensus-driven NBI classification system for identifying dysplasia and cancer in BE. The group reviewed 60 NBI images of nondysplastic BE, high-grade dysplasia, and esophageal adenocarcinoma to characterize mucosal and vascular patterns visible by NBI; these features were used to develop the BING criteria. We then recruited adult patients undergoing surveillance or endoscopic treatment for BE at 4 institutions in the United States and Europe, obtaining high-quality NBI images and performing histologic analysis of biopsies. Experts individually reviewed 50 NBI images to validate the BING criteria, and then evaluated 120 additional NBI images (not previously viewed) to determine whether the criteria accurately predicted the histology results. RESULTS: The BING criteria identified patients with dysplasia with 85% overall accuracy, 80% sensitivity, 88% specificity, 81% positive predictive value, and 88% negative predictive value. When dysplasia was identified with a high level of confidence, these values were 92%, 91%, 93%, 89%, and 95%, respectively. The overall strength of inter-observer agreement was substantial (κ = 0.681). CONCLUSIONS: The BING working group developed a simple, internally validated system to identify dysplasia and EAC in patients with BE based on NBI results. When images are assessed with a high degree of confidence, the system can classify BE with >90% accuracy and a high level of inter-observer agreement.

Perspectives on Low-grade Sarcomas: The Extraordinary Contributions of Sharon W. Weiss, MD.

Soft-tissue pathology encompasses a wide spectrum of neoplasms that represent some of the most challenging and problematic tumors in surgical pathology. Owing to the intensive work of dedicated pathologists, this once esoteric field has become increasingly well defined. In this review, Dr Sharon Weiss' monumental contributions to low-grade sarcomas, including low-grade fibromyxoid sarcoma/so-called hyalinizing spindle cell tumor, atypical lipomatous tumor/well-differentiated liposarcoma and dedifferentiated liposarcoma, epithelioid hemangioendothelioma, and dermatofibrosarcoma protuberans with fibrosarcomatous transformation will be discussed.

Correlation between endoscopic forceps biopsies and endoscopic mucosal resection with endoscopic ultrasound in patients with Barrett's esophagus with high-grade dysplasia and early cancer.

BACKGROUND: Patients with Barrett's esophagus (BE) and high-grade dysplasia (HGD) or intramucosal cancer (IMC) on endoscopic forceps biopsies are referred to endoscopic therapy even though forceps biopsies do not reflect the disease extent accurately. Endoscopic mucosal resection (EMR) and endoscopic ultrasound (EUS) are frequently used for staging prior to endoscopic therapy. Our aims were to evaluate: (1) if endoscopic forceps biopsies correlated with EMR histology in these patients; (2) the utility of EUS compared to EMR; and (3) if accuracy of EUS varied based on grade of differentiation of tumor. METHODS: This is a retrospective review of patients referred to endoscopic therapy of BE with HGD or early esophageal adenocarcinoma (EAC) who underwent EMR from 2006 to 2011. Age, race, sex, length of Barrett's segment, hiatal hernia size, number of endoscopies and biopsy results and EUS findings were abstracted. RESULTS: A total of 151 patients underwent EMR. In 50 % (75/151) of patients, EMR histology was consistent with endoscopic forceps biopsy findings. EMR resulted in change in diagnosis with upstaging in 21 % (32/151) and downstaging in 29 % (44/151). In patients with HGD on EMR, EUS staging was T0 in 74.1 % (23/31) but upstaged in 25.8 % (8/31). In patients with IMC on EMR, EUS findings were T1a in 23.6 % (9/38), upstaged in 18.4 % (7/38) and downstaged in 57.8 % (22/38). EUS accurately identified EMR histology in all submucosal cancers. Grade of differentiation was reported in 24 cancers on EMR histology. There was no correlation between grade and EUS staging. CONCLUSIONS: EUS is of limited utility in accurate staging of BE patients with HGD or early EAC. Endoscopic forceps biopsy correlated with EMR findings in only 50 % of patients. Irrespective of the endoscopic forceps biopsy results, all BE patients with visible lesions should be referred to EMR.

Broadening the Anatomic Landscape of Sclerosing Perineurioma: A Series of 5 Cases in Nonacral Sites.

Sclerosing perineurioma is a rare perineurioma variant thought to occur almost exclusively in digits and palms, predominantly in young adult men. It clinically presents as a solitary slow-growing nodule, sometimes associated with prior trauma. Since 01/01/2000, our institution has received 5 cases in consultation of sclerosing perineurioma presenting in atypical locations. Four of 5 patients were women. The median age at presentation was 45 years (range, 31-62 years). Sites included dorsal tongue, anterior neck, mid upper back, forearm, and proximal anterior thigh. Complete clinical histories were not available, although lesions were reported as subcentimeter nodules with at least 1 suspected to have formed after trauma. Histologically, all lesions were circumscribed to dermal/submucosal tumors. Some extended into subcutaneous fat. The neoplasms were composed of an admixture of bland spindled to epithelioid cells with uniform, wavy, thin-to-oval nuclei forming linear cords to whorled sheets in an extensively hyalinized stroma. Mitotic activity was inconspicuous. All tumors expressed epithelial membrane antigen and were negative for S100 protein. All cases stained for CD34 were positive (3/3). This series highlights a broader clinical presentation of sclerosing perineurioma than previously recognized. Acknowledgment of this anatomic variability should provide confidence to dermatopathologists faced with similar cases.

Risk stratification of patients with barrett's esophagus and low-grade dysplasia or indefinite for dysplasia.

BACKGROUND & AIMS: In patients with Barrett's esophagus (BE), low-grade dysplasia (LGD) is a risk factor for esophageal adenocarcinoma (EAC), progressing at variable rates. Patients at higher risk for progression could benefit from intervention. We assessed rates of progression of LGD and indefinite for dysplasia (IND) and risk factors for progression to high-grade dysplasia (HGD) and EAC. METHODS: We analyzed data from Cleveland Clinic Barrett's Registry on patients with BE and LGD or IND at least 1 year of follow-up from January 1, 2002 through December 31, 2012. Prevalent cases were those diagnosed at or within 1 year of the first endoscopy, and the rest were incident cases. RESULTS: Among 299 patients with BE and LGD or IND, there were 32 cases of HGD and 10 cases of EAC during a follow-up period of 1577.4 patient-years. The annual incidence rates were 2.4% (95% confidence interval [CI], 1.7%-3.3%) for HGD, 0.6% (95% CI, 0.3%-1.2%) for EAC, and 2.7% (95% CI, 1.9%-3.6%) for HGD or EAC. The rates were higher in men than in women with BE and LGD or IND. Prevalent cases were 3-fold more likely to progress than incident cases. Multifocality and nodules were associated with higher risk of progression to HGD or EAC. None of the patients with IND at index biopsy developed EAC. For every 5-year increase in age, chance of regression increased by 7% (P = .04). Also, for every 1-cm increase in BE length, probability of regression decreased by 6% (P = .016). LGD at index biopsy was associated with 56% lower chance of regression compared with IND (P < .001). CONCLUSIONS: On the basis of a database analysis of patients with BE, prevalent LGD, male sex, multifocality, and nodules were associated with higher risk for progression to EAC. Older age at LGD diagnosis, IND at index biopsy, and shorter BE length were associated with regression. These findings help in risk stratification of patients with BE and LGD or IND.

Current issues in Barrett's esophagus and Barrett's-related dysplasia.

Surgical pathologists frequently encounter biopsies in patients with Barrett's esophagus (BE), defined as replacement of the normal stratified squamous epithelium of the distal esophagus by metaplastic columnar epithelium containing goblet cells. Thus, one of the primary roles of the pathologist is to definitively identify goblet cells, best done on routine stained sections. It has recently been questioned as to whether goblet cells should be absolutely necessary to render a diagnosis of BE, given immunohistochemical and flow cytometric similarities between columnar-lined esophagus with and without goblet cells. Once a diagnosis of BE is rendered, the pathologist must state, using a simple classification, whether the biopsy is negative for dysplasia or shows dysplasia (low-grade dysplasia or high-grade dysplasia). However, there are a number of known pitfalls in distinguishing dysplasia from reactive epithelium, and it can be similarly difficult to distinguish low-grade dysplasia from high-grade dysplasia. In addition, there are some cases in which the distinction of high-grade dysplasia from intramucosal adenocarcinoma can be challenging. All of these issues are summarized in this paper.