Mucosal α4ß7+ Lymphocytes and MAdCAM+ Venules Predict Response to Vedolizumab in Ulcerative Colitis.

BACKGROUND: Therapeutic strategies for patients with ulcerative colitis (UC) are based on patient- and disease-related factors in combination with drug characteristics but fail to predict success in individual patients. A considerable proportion of UC patients do not respond to the biological vedolizumab. Therefore, pretreatment biomarkers for therapeutic efficacy are urgently needed. Mucosal markers related to the integrin-dependent T lymphocyte homing could be potent predictors. METHODS: We prospectively included 21 biological- and steroid-naive UC patients with moderate-to-severe disease activity planned to escalate therapy to vedolizumab. At week 0, before initiating treatment, colonic biopsy specimens were obtained for immunophenotyping and immunohistochemistry. Clinical and endoscopic disease activity were determined at week 16 after 4 infusions of vedolizumab. In addition, we retrospectively included 5 UC patients who were first treated with anti-tumor necrosis factor α before receiving vedolizumab to compare with biological-naive patients. RESULTS: Abundance of α4ß7 on more than 8% of all CD3+ T lymphocytes in colonic biopsies at baseline was predictive for responsiveness to vedolizumab (sensitivity 100%, specificity 100%). The threshold for the proportion of MAdCAM-1+ and PNAd+ of all venules in the biopsies predictive for responsiveness to vedolizumab was ≥2.59% (sensitivity 89%, specificity 100%) and ≥2.41% (sensitivity 61%, specificity 50%), respectively. At week 16, a significant decrease of α4ß7+CD3+T lymphocytes was demonstrated in responders (18% [12%-24%] to 8% [3%-9%]; P = .002), while no difference was seen in nonresponders (4% [3%-6%] to 3%; P = .59). CONCLUSIONS: UC responders to vedolizumab have a higher percentage of α4ß7+CD3+ T lymphocytes and a higher proportion of MAdCAM-1+ venules in colonic biopsies than nonresponders before initiating therapy. Both analyses could be promising predictive biomarkers for therapeutic response and may lead to more patient tailored treatment in the future.

Discrepancies in digital hematopathology diagnoses for consultation and expert panel analysis.

Digital pathology with whole-slide imaging (WSI) has a large potential to make the process of expert consultation and expert panel diagnosis more rapid and more efficient. However, comparison with the current methods is necessary for validation of the technique. In this study, we determined if digital assessment of whole-slide images of hematopathology specimens with a focus on the assessment of lymphoma can be used for consultation and panel diagnostics. Ninety-three histological specimens with a suspicion for lymphoma were assessed both with conventional microscopy and digital microscopy with a wash out period between assessments. A consensus diagnosis was based on full concordance between the pathologists or, in case of discordances, was reached at a joint session at a multi-headed microscope. In 81% of the cases, there was a full concordance between digital and light microscopical assessment for all three pathologists. Discordances between conventional microscopy and digital pathology were present in 3% of assessments. In comparison with the consensus diagnosis, discordant diagnoses were made in 5 cases with digital microscopy and in 3 cases with light microscopy. The reported level of confidence and need for additional investigations were similar between assessment by conventional and by digital microscopy. In conclusion, the performance of assessment by digital pathology is in general comparable with that of conventional light microscopy and pathologists feel confident using digital pathology for this subspecialty.

Overtreatment of Nonneoplastic Gallbladder Polyps due to Inadequate Routine Ultrasound Assessment.

BACKGROUND: The primary aim was to assess the diagnostic accuracy of routine ultrasound assessment for gallbladder polyps. The secondary aim was to identify the characteristics that differentiate neoplastic polyps from nonneoplastic polyps. METHODS: A total of 156 patients with histopathologically proven gallbladder polyps in 4 Dutch hospitals between 2003 and 2013 were included. Sensitivity and specificity of ultrasound for polyp size, number of polyps, and polyp type were assessed using histopathological findings as a reference standard. In addition, diagnostic accuracy of sonographic size ≥1 cm for neoplasia was assessed. Subgroup analysis for patients with polyps as primary indication for cholecystectomy was performed. The sonographic polyp characteristics on preoperative routine ultrasound were described. RESULTS: Fifty-six percent of gallbladder polyps were preoperatively identified on ultrasound, of which 31% were neoplastic. Sensitivity and specificity of ultrasound to estimate polyp size were 93 and 43% (subgroup; 92 and 33%). Sensitivity and specificity of sonographic polyp size ≥1 cm for neoplasia were 86 and 32% (subgroup; 94 and 26%). No specific sonographic characteristics for neoplastic polyps could be established due to lack of reporting. CONCLUSION: Routine ultrasound assessment of polyps is associated with overestimation of polyp size and low specificity of sonographic size ≥1 cm for neoplasia, which contributes to surgical overtreatment of nonneoplastic polyps.

Raising the Cut-Off Level of Anti-Tissue Transglutaminase Antibodies to Detect Celiac Disease Reduces the Number of Small Bowel Biopsies in Children with Type 1 Diabetes: A Retrospective Study.

OBJECTIVE: To study the optimal cut-off value for anti-tissue transglutaminase type 2 IgA antibodies (TG2A) in serum to select for diagnostic small bowel biopsies for celiac disease in children with type 1 diabetes mellitus. STUDY DESIGN: Children with type 1 diabetes mellitus with elevated TG2A titers and duodenal biopsies performed during the course of their diabetes treatment were included. Anti-endomysial antibodies were recorded if present. The optimal TG2A cut-off value, expressed as the ratio between obtained value and upper limit of normal (ULN), was determined using receiver operating characteristic curve analysis and compared with the cut-off value used in the European Society for Pediatric Gastroenterology, Hepatology and Nutrition guidelines in terms of sensitivity, specificity, positive and negative predictive value. RESULTS: We included 63 children. The optimal cut-off value for performing biopsies is demonstrated to be 11 times the ULN. Raising the cut-off value from 3 times the ULN to 11 times the ULN changed sensitivity from 96% to 87% and increased specificity from 36% to 73%, increased the positive predictive value from 88% to 94% and lowered negative predictive value from 67% to 53%. The percentage of normal histology was decreased from 12% to 6%. CONCLUSIONS: Increasing the TG2A cut-off value for performing duodenal biopsies in children with type 1 diabetes mellitus and suspected celiac disease leads to a substantial reduction of unnecessary biopsies. We advocate to adapt the European Society for Pediatric Gastroenterology, Hepatology and Nutrition 2012 guidelines for this group of children, including monitoring patients with TG2A levels of less than 11 times the ULN over time.

Development of Mucosal PNAd+ and MAdCAM-1+ Venules during Disease Course in Ulcerative Colitis.

PNAd and MAdCAM-1 addressins on venules are of importance in T-cell homing and potential therapeutic targets in ulcerative colitis (UC). Normally, PNAd+ high endothelial venules (HEVs) are only present in lymphoid organs, whereas small numbers of MAdCAM-1+ venules can be seen in non-lymphoid tissue. We aimed to study their presence in the intestinal mucosa of UC patients at diagnosis and during follow-up, and their correlation with disease activity. Colonic biopsy specimens of 378 UC patients were analyzed by immunohistochemistry for CD3, CD20, ERG, MECA-79 (PNAd) and MECA-376 (MAdCAM-1) and compared to healthy controls (HC). The proportion of PNAd+HEVs in UC at diagnosis was 4.9% (IQR 2.0%-8.3%), while none were detected in HC. During follow-up, PNAd+HEVs completely disappeared in remission (n = 93), whereas the proportion in active disease was similar to baseline (n = 285, p = 0.39). The proportion of MAdCAM-1+venules in UC at baseline was 5.8% (IQR 2.6-10.0). During follow-up, the proportion in remission was comparable to diagnosis, but upregulated (7.5% (IQR 4.4-10.9), p = 0.001) in active disease. In conclusion, PNAd+HEVs appear in UC during active inflammation which could thus serve as a marker for disease activity, whereas MAdCAM-1+venules remain present after inflammation is resolved and increase after subsequent flares, reflecting chronicity and potentially serving as a therapeutic target.

Interobserver, intraobserver, and interlaboratory variability in reporting pT4a colon cancer.

Clinical significance of the pT4 category in colon cancer is increasing with several therapeutic implications. The aim of this study was to evaluate variability in diagnosing pT4a colon cancer. Twelve pathologists classified 66 preselected scanned Hematoxylin/Eosin-stained slides with tumor cells at a distance of 25-1500 µm (n = 22), 0-25 µm (n = 22), or on (n = 22) the peritoneal surface. Inter- and intraobserver variability were calculated using Kappa statistics. For interlaboratory variability, pathology reports of pT3 and pT4a colon cancer were extracted from the Dutch Pathology Registry between 2012 and 2015. The proportion of pT4a (pT4a/(pT3+pT4a)) was compared between 33 laboratories. Potential risk of understaging was assessed by determining the average number of blocks taken from pT3 and pT4a N0-2M0 tumors with metachronous peritoneal metastasis. Interobserver variability among 12 pathologists was 0.50 (95%CI 0.41-0.60; moderate agreement). Intraobserver variability (8 pathologists) was 0.71 (substantial agreement). A total of 7745 reports with pT3 or pT4aN0-2M0 colon cancer from 33 laboratories were included for interlaboratory analysis. Median percentage of pT4a was 15.5% (range 3.2-24.6%). After adjustment for case mix, 8 labs diagnosed pT4a significantly less or more frequently than the median lab. Metachronous peritoneal metastases were histologically verified in 170 of 6629 pT3 and in 129 of 1116 pT4a tumors, with a mean number of blocks of 4.03(SD 1.51) and 4.78 (SD 1.76) taken from the primary tumors, respectively (p < 0.001). A substantial variability in diagnosing pT4a colon cancer exists, both at pathologist and laboratory level. Diagnosis of pT4a stage appears to be challenging and there is a need for standardizing assessment of this pathological entity.

Pathology Image Exchange: The Dutch Digital Pathology Platform for Exchange of Whole-Slide Images for Efficient Teleconsultation, Telerevision, and Virtual Expert Panels.

Among the many uses of digital pathology, remote consultation, remote revision, and virtual slide panels may be the most important ones. This requires basic slide scanner infrastructure in participating laboratories to produce whole-slide images. More importantly, a software platform is needed for exchange of these images and functionality to support the processes around discussing and reporting on these images without breaching patient privacy. This poses high demands on the setup of such a platform, given the inherent complexity of the handling of digital pathology images. In this article, we describe the setup and validation of the Pathology Image Exchange project, which aimed to create a vendor-independent platform for exchange of whole-slide images between Dutch pathology laboratories to facilitate efficient teleconsultation, telerevision, and virtual slide panels. Pathology Image Exchange was released in April 2018 after technical validation, and a first successful validation in real life has been performed for hematopathology cases.

Sequencing of RAS/RAF pathway genes in primary colorectal cancer and matched liver and lung metastases

Background: Mutations in the RAS/RAF pathway predict resistance to anti-epidermal growth factor receptor antibodies in colorectal cancer (CRC), and may be targets for future therapies. This study investigates concordance of BRAF, HRAS, KRAS, NRAS and PIK3CA mutation status in primary CRC with matched liver (n = 274), lung (n = 114) or combined liver and lung metastases (n = 14). Methods: Next generation sequencing was performed on DNA from formalin-fixed paraffin embedded CRC and matched liver and/or lung metastases, for recurrent mutations in BRAF, HRAS, KRAS, NRAS and PIK3CA and using the single-molecule molecular inversion probe method. Results: Paired sequencing results on all five genes were reached in 249 of the 402 cases (62%). The obtained number of unique reads was not always sufficient to confidently call the absence or presence of mutations for all regions of interest. The mutational status of matched pairs was highly concordant; 91.1% concordance for all five genes, 95.5% for KRAS, 99.1% for NRAS. Lung metastases more often harboured RAS mutations compared to liver metastases (71% vs. 48%, p < 0.001). Conclusions: In this large series of CRC we show that both primary tumors and corresponding metastases can be used to determine the mutational status for targeted therapy, given the high concordance rates. Next generation sequencing including a single molecule tags is feasible, however in combination with archival formalin-fixed paraffin embedded material is limited by coverage depth.

Prevalence of Upper Gastrointestinal Lesions at Primary Diagnosis in Adults with Inflammatory Bowel Disease.

BACKGROUND: The prevalence of upper gastrointestinal (GI) involvement in adult inflammatory bowel disease has mostly been studied in patients with long-standing disease. The aim of this study was to prospectively evaluate the prevalence of upper GI involvement in a consecutive series of newly diagnosed, treatment-naive adult patients with inflammatory bowel disease, irrespective of upper GI tract symptoms. METHODS: Consecutive patients with suspected inflammatory bowel disease underwent combined ileocolonoscopy and upper endoscopy with biopsies. Patients diagnosed with either Crohn's disease (CD) or ulcerative colitis (UC), denying use of nonsteroidal anti-inflammatory drug, were included in the study. Helicobacter pylori infection was diagnosed histologically and positive patients were excluded from the analysis. Endoscopic and histologic lesions in the stomach and duodenum were recorded. Upper GI location (+L4) was defined as a combination of endoscopic and histological lesions. RESULTS: A total of 152 patients (108 CD and 44 UC) were analyzed. Endoscopic lesions were only seen in patients with CD (60 of 108, 55%). Histological lesions were present in both patients with CD and patients with UC: focally enhanced gastritis in 58 CD (54%) and 10 UC (23%), granulomas in 30 CD (28%). Upper GI disease location was diagnosed in 44 patients with CD (41%) and no patients with UC. Upper GI tract symptoms were reported in 14 of 44 patients (32%) with upper GI location. CONCLUSIONS: A high prevalence of upper GI involvement was observed in newly diagnosed patients with CD, with a majority of the patients being asymptomatic. Focally enhanced gastritis was common in both patients with CD and patients with UC, whereas granulomatous inflammation was restricted to patients with CD.

[Mastitis as a symptom of malignancy]. / Mastitis als uiting van een maligniteit.

Several conditions can mimic the clinical presentation of inflammatory breast cancer. Three women presented with a swollen, red and painful breast which turned out to be inflammatory breast cancer after being treated as infectious mastitis. Non-puerperal bacterial mastitis may be confused with inflammatory breast cancer, leading to potentially preventable delays in diagnosis and treatment. The skin changes in inflammatory breast cancer are caused by tumour emboli within the dermal lymphatics, and not by infiltration of inflammatory cells as is suggested by the nomenclature. Patients who are treated for suspected mastitis without clinical improvement in one week should be referred to outpatient care in the surgery department to exclude underlying malignancy.

Rising incidence of celiac disease in the Netherlands; an analysis of temporal trends from 1995 to 2010.

OBJECTIVE: According to screening studies, celiac disease (CD) is prevalent in Western Europe. Actual prevalence tends to be much lower. The width of this actual gap is determined by the balance between disease symptoms and the "case-finding" capabilities of the healthcare system. Therefore, we conducted a nationwide study to determine the temporal trends in the incidence in the Netherlands including a focus on demographic aspects. MATERIALS AND METHODS: We performed a nationwide search in the Dutch Pathology Registry (PALGA) to identify all biopsy-proven cases of CD in five different years between 1995 and 2010. Furthermore, demographic profiles and socioeconomic status (SES) of patients were studied. RESULTS: The overall incidence of CD increased from 2.72 (confidence interval [CI] 2.46-2.99) in 1995 to 6.65 (CI 6.27-7.06) per 100,000 inhabitants in 2010. No significant regional differences were noticed. In men, rates increased from 2.28 (CI 1.95-2.65) to 4.71 (CI 4.25-5.20) per 100,000 in 2010. In women, the increase was from 3.27 (CI 2.88-3.70) to 8.66 (CI 8.04-9.31) per 100,000 in 2010. A trend toward leveling of incidence was observed from 2008 to 2010. Patients diagnosed during childhood live in areas with a higher SES compared with patients diagnosed at adult age. CONCLUSION: The incidence of biopsy-proven CD in the Netherlands increased almost threefold between 1995 and 2010. In areas with a higher SES, relatively more children were diagnosed.

Sequential immunohistochemistry: a promising new tool for the pathology laboratory.

AIMS: Current immunohistochemical methods to study the expression of multiple proteins in a single tissue section suffer from several limitations. In this article, we report on sequential immunohistochemistry (S-IHC), a novel, easy method that allows the study of numerous proteins in a single tissue section, while requiring very limited optimization. METHODS AND RESULTS: In S-IHC, a tissue section is stained for multiple antibodies, with intermediate scanning of the section and elution of chromogen and antibodies. Overlays are made of the digital images, allowing assessment of multiple proteins in the same tissue section. We used S-IHC to study nine nodular lymphocyte-predominant Hodgkin lymphomas (NLPHLs) and 10 T-cell-rich and histiocyte-rich diffuse large B-cell lymphomas (T/HRBCLs) for expression of cyclin D1, CD20, and CD68. We observed cyclin D1 expression in single tumour cells in 44% of NLPHLs and 60% of T/HRBCLs. Comparison of S-IHC with classic single immunohistochemical staining revealed discrepancies in eight cases (42%), demonstrating the difficulty of differentiating tumour cells from histiocytes on morphological grounds, and stressing the additional value of S-IHC. CONCLUSIONS: For research and diagnostic purposes, S-IHC is a promising technique that assesses the expression of numerous proteins in single tissue sections with complete architectural information, allowing phenotypic characterization of single cells.

Evaluation of a panel of expert pathologists: review of the diagnosis and histological classification of Hodgkin and non-Hodgkin lymphomas in a population-based cancer registry.

Abstract Correct histological classification of malignant lymphomas is important but has always been a difficult challenge. Since 2001 the World Health Organization (WHO) classification has been used, which should make it easier to define distinct disease entities. The purpose of this study was to evaluate the usefulness of a panel of expert hematopathologists in reviewing the diagnosis of malignant lymphomas and to examine whether the discordance between primary and panel diagnoses has declined throughout the years. All patients with a primary malignant lymphoma diagnosed between 2000-2001 and 2005-2006 were identified through the population based cancer registry. All diagnoses were reviewed by a panel of three expert pathologists. In 2000-2001, 344 patients were included, and in 2005-2006, 370 patients. The overall discordance rate decreased from 14% in 2000-2001 to 9% in 2005-2006 (p = 0.06). We were able to identify lymphoma subgroups with the highest discordance rates and lowest discordance rates (mantle cell lymphoma and classical Hodgkin lymphoma), which remained unchanged throughout the years. Based on these results we would propose to review all cases of malignant lymphoma with the exception of mantle cell lymphoma and classical Hodgkin lymphoma, when the initial pathologist has no doubt about the diagnosis.

Hepatic steatosis in morbidly obese patients undergoing gastric bypass surgery: assessment with open-system 1H-MR spectroscopy.

OBJECTIVE: The purpose of this study was to assess, with histopathologic control, the use of open-system 1-T (1)H MR spectroscopy for the evaluation of hepatic steatosis in morbidly obese patients undergoing gastric bypass surgery. SUBJECTS AND METHODS: Patients underwent (1)H MR spectroscopy (MRS) for the assessment of steatosis before and 3 months after surgery. Liver biopsy was performed during surgery. Hepatic steatosis was expressed as the ratio of fat peak area to cumulative water and fat peak areas. Histopathologic percentage of steatosis was graded as none (0-5%), mild (5-33%), moderate (33-66%), or severe (> 66%). The accuracy of (1)H-MRS and Spearman correlation coefficient were calculated. Differences between groups were assessed with the Wilcoxon signed rank and Mann-Whitney tests. RESULTS: The study included 38 patients (median age, 45.5 years; median body mass index, 47.7). Before surgery, median steatosis measured with (1)H-MRS was 5.8%. The accuracy of (1)H-MRS was 89% (32/36), and the (1)H-MRS findings correlated with the histopathologic assessment of steatosis (r = 0.85, p < 0.001). With (1)H-MRS, no steatosis was discriminated from mild steatosis (p = 0.011), mild was discriminated from moderate steatosis (p < 0.001), and moderate was discriminated from severe steatosis (p = 0.021). Three months after surgery, steatosis had decreased to 3.1% (p < 0.001). The prevalence of hepatic steatosis measured with (1)H-MRS decreased from 53% to 32%. CONCLUSION: In the care of morbidly obese patients undergoing assessment of hepatic steatosis and changes in steatosis after gastric bypass surgery, (1)H-MRS with an open 1-T MRI system is feasible. Measurements of hepatic fat with (1)H-MRS are accurate and correlate with clinical and histopathologic results.

Protein profiling in pathology: analysis and evaluation of 239 frozen tissue biopsies for diagnosis of B-cell lymphomas.

PURPOSE: We determined the potential value of protein profiling of tissue samples by assessing how precise this approach enables discrimination of B-cell lymphoma from reactive lymph nodes, and how well the profiles can be used for lymphoma classification. EXPERIMENTAL DESIGN: Protein lysates from lymph nodes (n=239) from patients with the diagnosis of reactive hyperplasia (n=44), follicular lymphoma (n=63), diffuse large B-cell lymphoma (n=43), mantle cell lymphoma (n=47), and chronic lymphocytic leukemia/small lymphocytic B-cell lymphoma (n=42) were analysed by SELDI-TOF MS. Data analysis was performed by (i) classification and regression tree-based analysis and (ii) binary and polytomous logistic regression analysis. RESULTS: After internal validation by the leave-one-out principle, both the classification and regression tree and logistic regression classification correctly identified the majority of the malignant (87 and 96%, respectively) and benign cases (73 and 75%, respectively). Classification was less successful since approximately one-third of the cases of each group were misclassified according to the histological classification. However, an additional mantle cell lymphoma case that was misclassified as chronic lymphocytic leukemia/small lymphocytic B-cell lymphoma initially was identified based on the protein profile. CONCLUSIONS AND CLINICAL RELEVANCE: SELDI-TOF MS protein profiling allows for reliable identification of the majority of malignant lymphoma cases; however, further validation and testing robustness in a diagnostic setting is needed.

The staging of gastritis with the OLGA system by using intestinal metaplasia as an accurate alternative for atrophic gastritis.

BACKGROUND: The OLGA (operative link on gastritis assessment) staging system is based on severity of atrophic gastritis (AG). AG remains a difficult histopathologic diagnosis with low interobserver agreement, whereas intestinal metaplasia (IM) is associated with high interobserver agreement. OBJECTIVE: The aim of this study was to evaluate whether a staging system based on IM is preferable to estimate gastric cancer risk. DESIGN AND SETTING: Prospective multicenter study. PATIENTS: A total of 125 patients previously diagnosed with gastric IM or dysplasia. INTERVENTIONS: Surveillance endoscopy with extensive biopsy sampling. MAIN OUTCOME MEASUREMENTS: Three pathologists graded biopsy specimens according to the Sydney classification. Interobserver agreement was analyzed by kappa statistics. In the OLGA, AG was replaced by IM, creating the OLGIM. RESULTS: Interobserver agreement was fair for dysplasia (kappa = 0.4), substantial for AG (kappa = 0.6), almost perfect for IM (kappa = 0.9), and improved for all stages of OLGIM compared with OLGA. Overall, 84 (67%) and 79 (63%) patients were classified as stage I-IV according to OLGA and OLGIM, respectively. Of the dysplasia patients, 5 (71%) and 6 (86%) clustered in stage III-IV of OLGA and OLGIM, respectively. LIMITATION: Prospective studies should confirm the correlation between gastric cancer risk and OLGIM stages. CONCLUSION: Replacement of AG by IM in the staging of gastritis considerably increases interobserver agreement. The correlation with the severity of gastritis remains at least as strong. Therefore, the OLGIM may be preferred over the OLGA for the prediction of gastric cancer risk in patients with premalignant lesions.