Search

Objectives DNA integrity number (DIN) is a metric for assessing DNA degradation, calculated based on electrophoresis using the Agilent TapeStation System. The utility of DIN as a diagnostic indicator of sufficient DNA quality in clinical next-generation sequencing (NGS) has not been well described. Methods We evaluated the DINs of 166 tumor formalin-fixed, paraffin-embedded (FFPE) tissue samples submitted for 124-gene panel sequencing. We also investigated a new metric on the electropherogram that could improve the predictive accuracy of the DIN. Results A DIN cutoff of 2.5 discriminated samples with successful analysis (n = 143) from samples with failed analysis (n = 23), with a sensitivity of 0.84 and a specificity of 0.78 (area under the curve [AUC] = 0.88). The DIN was positively correlated with the mean coverage (r = 0.72, P < .0001) but could not discriminate success from failure when the DIN was below 2.5 (negative predictive value, 0.44). We introduced a new metric, the peak/base ratio, that distinguished success from failure with higher accuracy than the DIN (cutoff = 1.6; sensitivity = 0.98, specificity = 0.83, and AUC =0.96). Conclusions To predict successful NGS, the DNA quality of FFPE tissue can be easily and reliably assessed using the DIN and peak/base ratio.

Recent advances in magnifying endoscopy with narrow-band imaging/blue laser imaging have aided in the diagnosis of gastrointestinal lesions. However, it requires knowledge of the relationship between magnifying endoscopic and histopathological images. We propose a novel method which makes possible a complete correspondence between magnifying endoscopic and histopathological images at the single glandular duct level. The KOTO method II enables three-dimensional visualization of the correlation between the endoscopic surface pattern of the mucosa and histopathological images. This method may be helpful in the development of diagnosis using magnifying endoscopy.

Objectives Little is known about the usefulness of magnifying endoscopy with crystal violet staining (ME-CV) for the diagnosis of duodenal tumors. We assessed the ability of ME-CV to distinguish Vienna classification (VCL) category 4/5 (C4/5) from category 3 (C3) non-ampullary duodenal epithelial tumors (NADETs). Methods A total of 76 NADETs were studied. We retrospectively analyzed the diagnostic values of the white light endoscopy (WLE) scoring system and the ME-CV algorithm with receiver operating characteristic (ROC) curves, and three endoscopists calculated the sensitivity, specificity, accuracy, and the area under the curve (AUC) of each. The diagnostic values were tested among NADETs overall and among subgroups of tumors with gastric, gastrointestinal or intestinal mucin phenotypes. Inter-observer agreement of the diagnostic results was also calculated. Results According to the VCL, 54 lesions (71.1%) were regarded as C3 and 22 lesions (28.9%) as C4/5. The sensitivity, specificity, accuracy and AUC of ME-CV were higher than those of the WLE scoring system (63.6 vs 54.5, 85.2 vs 75.9, 78.9 vs 69.7, 0.744 vs 0.652, respectively). Inter-observer agreements of the WLE scoring system and ME-CV were both moderate (kappa 0.45 and 0.41). ME-CV had higher sensitivity, specificity, accuracy and AUC than those of the WLE scoring system among the gastric and intestinal phenotypes of NADETs. Conclusions ME-CV is appropriate for the diagnosis of C4/5 and C3 NADETs.

BACKGROUND/AIMS Magnifying endoscopic classification systems, such as the Japan narrow-band imaging (NBI) Expert Team (JNET) classification, have been widely used for predicting the histologic diagnosis and invasion depth of colorectal epithelial tumors. However, disagreement exists among observers regarding magnifying endoscopic diagnosis, because these classification systems are subjective. We herein investigated the utility of endoscopic microvascular density (eMVD) calculated from magnifying NBI endoscopic images in colorectal tumors. METHODS We reviewed magnifying NBI endoscopic images from 169 colorectal epithelial tumors (97 adenomas, 72 carcinomas/high-grade dysplasias) resected endoscopically or surgically. The eMVD on magnifying NBI endoscopic images was evaluated using image-editing software, and relationships between eMVD and clinical, endoscopic, and pathological findings were retrospectively analyzed. RESULTS The eMVD in carcinomas (0.152 ± 0.079) was significantly higher than that in adenomas (0.119 ± 0.059, P< 0.05). The best cutoff value for distinguishing carcinoma from adenoma was 0.133. Sensitivity, specificity, and accuracy were 56.9%, 67.0%, and 62.7%, respectively. In addition, JNET type 2B tumors showed significantly higher eMVD (0.162 ± 0.079) compared to type 2A tumors (0.111 ± 0.050, P< 0.05). CONCLUSIONS The eMVD as determined by magnifying NBI endoscopy is considered to be a possible objective indicator for differentiating colorectal carcinomas from adenomas.

BACKGROUND Trastuzumab deruxtecan (T-DXd) has shown promising efficacy against human epidermal growth factor receptor 2 (HER2)-positive gastric and gastroesophageal junction (GEJ) adenocarcinomas. The efficacy of T-DXd rechallenge, however, has remained unclear. This is the first report of a dramatic response to T-DXd rechallenge in a patient with HER2-positive GEJ adenocarcinoma after confirmation of HER2 overexpression immediately prior to the rechallenge. CASE REPORT A 67-year-old man was diagnosed with HER2-positive gastric cardia (or GEJ) adenocarcinoma with lymph node and liver metastases. Initial T-DXd therapy was started as fourth-line chemotherapy. The best response was partial, and progression-free survival was 5.6 months. After an immune checkpoint inhibitor-based regimen, a rechallenge with T-DXd was planned as a seventh-line treatment. HER2 overexpression was confirmed by re-biopsy immediately before the rechallenge. He is currently receiving T-DXd without progression or severe treatment-related adverse events. CONCLUSIONS This is the first case report of a response to T-DXd rechallenge in a patient with HER2-positive gastric cancer. This rechallenge could be considered a treatment strategy for HER2-positive gastric cancer, for cases in which the initial T-DXd treatment was effective. Confirmation of HER2 overexpression and re-biopsy immediately before the rechallenge would be important for this strategy.

Although microRNAs (miRNAs) play an important role in invasive tumor lesions, which involve cancer tissues mixed with stromal tissues, the differences in miRNA expression between cancer and stromal cells remain unclear. We selected 13 miRNAs and examined their differential expression patterns in cancer gland cells and surrounding stromal cells isolated from 24 colorectal cancer (CRC) specimens using a crypt isolation method. Although six miRNAs were upregulated in gland cells, only three were upregulated in the corresponding stromal cells, in the cancer compared with non-cancer specimens. Next, we examined the differences in miRNA expression between isolated cancer gland and stromal cells. Five miRNAs showed statistical differences in their cancer-related differential expression patterns between isolated cancer gland and stromal cells. We then compared these miRNA expression patterns in isolated cancer gland and stromal cells with those in fresh intact tumor tissues, consisting of cancer nests and stromal tissue, obtained from the 24 CRCs. The expression patterns of three miRNAs in the intact cancer tissue samples did not correspond with those in the isolated components. Identification of the expression patterns of miRNAs in both the cancer gland and stromal cell components of the tumor microenvironment greatly contributes to evaluating epigenetic regulation in CRC.

Little is known about the risk factors for post endoscopic submucosal dissection (post-ESD) bleeding with anticoagulant therapy. We aimed to investigate the risk factors for post-ESD bleeding for early gastric cancer (EGC) with an emphasis on anticoagulant therapy. We retrospectively analyzed 2355 EGCs, including 137 lesions in patients treated under anticoagulants. Clinicopathological findings were evaluated between lesions in patients with and without anticoagulant therapy with propensity score matching analysis. The factors associated with post-ESD bleeding were analyzed with multivariate analysis with a logistic regression method. After propensity score matching, post-ESD bleeding was significantly more frequent in lesions of patients with than without anticoagulant therapy (11.7% vs 1.5%, respectively; P = 0.001). A univariate analysis revealed that anticoagulant therapy, heparin bridge therapy, undifferentiated type, deep submucosal invasion, and resected specimen size were associated with post-ESD bleeding. A multivariate analysis revealed anticoagulant therapy (OR 23.1, 95% CI 3.61–147.52) and resected specimen size (OR 1.03, 95% CI 1.00–1.06) to be independent factors associated with post-ESD bleeding. Anticoagulant therapy and resected specimen size were risk factors associated with post-ESD bleeding for EGC.

Background/Aims: To evaluate gastric early differentiate-type carcinogenesis, we attempted to identify clinicopathological and biological differences in differentiated-type minute intramucosal neoplasia (MIMN), which was defined as a tumor with a diameter of < 5 mm. Methods: We examined clinicopathological findings and biological factors, including TP53 overexpression, mucin phenotype, Ki-67-positive rate, MLH1, intranuclear accumulation of β-catenin, and DNA methylation status (low methylation epigenotype [LME], intermediate methylation epigenotype, and high methylation epigenotype [HME]) in MIMNs. In addition, non-MIMNs were also analyzed. In the present study, MIMN and non-MIMN were also examined based on low-grade dysplasia, high-grade dysplasia, and intramucosal cancer (IMC). Results: In clinicopathological findings, there were significant differences in sex ratios and tumor locations between MIMNs and non-MIMNs. Among the examined biological factors, no significant differences in the frequencies of biological factors were observed between the 2 intramucosal neoplasia types. However, the frequency of intranuclear accumulation of β-catenin was higher in non-MIMNs than in MIMNs. Finally, although the frequency of HME was significantly lower in MIMNs than in non-MIMNs, the opposite was observed for LME. Conclusions: The current finding suggested that DNA methylation and accumulation of β-catenin were closely associated with tumor development from MIMN to non-MIMN.

Little is known about the long-term outcomes and prognostic factors with non-curative endoscopic submucosal dissection (ESD) in elderly patients with early gastric cancer. Clinicopathological findings and long-term outcomes were evaluated in 87 patients with early gastric cancer (EGC) aged ≥ 75 years who were treated with non-curative ESD. Prognostic factors for overall survival (OS) were analyzed with the Kaplan–Meier method and a Cox proportional hazards model. During the follow-up period, among 27 patients who died of any cause, only one patient died of gastric cancer. OS probabilities after 3 and 5 years were 89.7% and 79.3%, respectively. Univariate analyses revealed that Eastern Cooperative Oncology Group performance status 2–3, Charlson comorbidity index (CCI) ≥ 3, neutrophil/lymphocyte ratio ≥ 3.3, prognostic nutritional index

Recent advances in magnifying endoscopy with narrow-band imaging/blue laser imaging have aided in the diagnosis of gastrointestinal lesions. However, it requires knowledge of the relationship between magnifying endoscopic and histopathological images. We propose a novel method which makes possible a complete correspondence between magnifying endoscopic and histopathological images at the single glandular duct level. The KOTO method II enables three-dimensional visualization of the correlation between the endoscopic surface pattern of the mucosa and histopathological images. This method may be helpful in the development of diagnosis using magnifying endoscopy.

MicroRNAs (miRNAs) are potential biomarkers of neoplastic lesions, but additional information on dysregulated miRNA expression during progression of the adenoma-adenocarcinoma sequence may be helpful to identify the role of miRNAs in this sequence. We examined the expression levels of 13 miRNAs (hsa-miRNA-19a-3p, hsa-miRNA-21-5p, hsa-miRNA-27a-3p, hsa-miRNA-27b-3p, hsa-miRNA-31-5p, hsa-miRNA-34b-3p, hsa-miRNA-125b-5p, hsa-miRNA-143-3p, miRNA-191-5p, hsa-miRNA-193b-3p, hsa-miRNA-195-5p, hsa-miRNA-206 and hsa-let-7a-5p) that are closely associated with colorectal carcinogenesis in 40 conventional adenomas (tubular and tubulovillous adenomas), 20 intramucosal carcinomas (IMCs) and 60 invasive colorectal cancers (iCRCs) using reverse-transcription polymerase chain reaction. These 120 tumors were divided into two cohorts, that is, cohort 1 (60 cases) and cohort 2 (for validation; 60 cases). We analyzed the expression levels of these miRNAs in the first step (adenoma→IMC) and second step IMC→iCRC) of the adenoma-carcinoma sequence in both cohorts. Although no significant differences in the expression of any of the 13 miRNAs were found between adenomas and IMCs consistently in both cohorts, the expression levels of hsa-miRNA-125b-5p, hsa-miRNA-143-3p, and hsa-miRNA-206 were significantly upregulated in iCRC in both cohorts compared with those in IMC. The current results suggest that certain miRNAs, including hsa-miRNA-125b-5p, hsa-miRNA-143-3p and hsa-miRNA-206, are candidate markers that play critical roles in the progression of IMC to iCRC.

Gastric intraepithelial foveolar type neoplasia (IEFN) is not well defined. In addition, atrophic mucosa (AM) is an important issue to consider when evaluating gastric tumorigenesis. Here, we assessed the clinicopathological characteristics and molecular alterations contributing to the development of IEFN compared with intestinal type neoplasia. We examined the clinicopathological and molecular features of 42 cases of IEFN with low-grade dysplasia (LGD) and those of 77 cases of intraepithelial intestinal type neoplasia (IEIN) with LGD. The clinicopathological and molecular features examined included the AM status, mucin phenotype expression, CDX2 expression, p53 overexpression, β-catenin intranuclear accumulation, microsatellite instability (MSI), DNA methylation status (low methylation epigenotype [LME], intermediate ME, or high ME), allelic imbalances (AIs), and APC promoter 1B mutations. There were no differences in the frequencies of AM and rates of CDX2 expression between IEFN and IEIN cases. Although no differences in the frequencies of p53 overexpression and MSI were observed between the two histological types, intranuclear expression of β-catenin was significantly higher in IEIN than in IEFN. In addition, although the rate of LME was significantly higher in IEFN cases than in IEIN cases, IEFN was characterized by AIs at multiple foci. Finally, mutation of the APC promoter 1B, which is a characteristic of gastric adenocarcinoma and proximal polyposis of the stomach (potentially resembling IEFN), was detected in only one IEFN case. These findings suggested that IEFN may be an independent entity in terms of molecular alterations including the presence of multiple AIs and LME. Electronic supplementary material The online version of this article (10.1007/s00428-020-02846-0) contains supplementary material, which is available to authorized users.

Crystal-storing histiocytosis (CSH) is a rare phenomenon in which crystalline material accumulates in the cytoplasm of histiocytes. Localized gastric CSH is an extremely rare condition. We report a case of localized gastric CSH in a 72-year-old female who presented with diffuse granular mucosa in the gastric fundus and body endoscopically. Biopsy specimens from the stomach showed accumulation of crystal-storing histiocytes, and the crystalline material was immunohistochemically positive for kappa light chains and polyclonal heavy chains. There were no crystal-storing histiocytes in other organs. For the past 5 years, the gastric CSH lesion has remained without any change, and no neoplastic or lymphoproliferative disease has developed. Once the diagnosis of CSH is established, it is necessary to check for an underlying lymphoplasmacytic disorder. However, some cases of localized gastric CSH are not associated with lymphoplasmacytic neoplasia, and these tend to have a good prognosis. Keywords: Crystal-storing histiocytosis, Stomach, Immunohistochemistry, Ultrastructure

Background/Aims: Gastric-type differentiated adenocarcinoma (GDA) of the stomach is a rare variant of gastric cancer that is highly infiltrating and exhibits early metastasis. However, the endoscopic and pathological features of “early-stage” GDA remain unknown. The aim of this study is to characterize early-stage GDA. Methods: We retrospectively enrolled 479 differentiated-type early gastric cancer cases who underwent endoscopic submucosal dissection (ESD). GDA cases were selected based on morphology and immunohistochemistry. Clinicopathological data were compared between gastric- and intestinal-type differentiated adenocarcinomas (IDAs). Results: Thirteen lesions were classified as GDAs. GDAs as well as IDAs showed irregular microvascular and microsurface patterns with clear demarcation line on magnifying endoscopy with narrow band imaging (M-NBI). The rate of pathological misdiagnosis of GDAs in biopsy specimens was higher than that of IDAs (p = 0.016). GDA was significantly associated with positive lymphovascular invasion (p = 0.016). There was one intramucosal lesion with lymphatic invasion in GDA. Conclusions: Although M-NBI is useful to detect GDA, the pathological diagnosis of GDAs in biopsy specimens often remains challenging. When suspicious lesions are not diagnosed as GDA, they should be followed up intensively, or diagnostic ESD has to be performed. ESD specimens should be carefully evaluated because of a higher incidence of lymphovascular invasion.

Aim The aim of your study is to characterize serrated lesions according to their molecular patterns, specifically BRAF/KRAS mutation, methylation, and microsatellite statuses. We evaluated the molecular patterns of 163 serrated lesions, including 37 microvesicular hyperplastic polyps, 73 sessile serrated adenomas/polyps (SSA/Ps), 31 traditional serrated adenomas, and 22 SSA/Ps with cytological dysplasia/adenocarcinoma. Methods Mutations in BRAF (V600E)/KRAS (exon 2) and microsatellite status [microsatellite stability (MSS) vs. MSI] were examined using a pyrosequencer and the PCR-based microsatellite method, respectively. DNA methylation status was classified as low (LME), intermediate (IME), or high methylation epigenotype (HME) according to a PCR-based two-step method. In addition, mucin and annexin A10 expression was examined. Finally, we performed a hierarchical clustering analysis of the BRAF/KRAS mutation, DNA methylation, and microsatellite statuses. Results The molecular patterns observed in the serrated lesions could be divided into five subgroups: lesions characterized by (1) BRAF mutation, HME, and MSI; (2) BRAF mutation, HME, and MSS; (3) BRAF mutation, LME/IME, and MSS; (4) no BRAF/KRAS mutations, LME/IME, and MSS; and (5) KRAS mutation, LME/IME, and MSS. In addition, we demonstrated that these observed molecular patterns help identify the associations of the molecular patterns and markers (i.e., mucin and annexin A10) with the clinicopathological findings, including histological features and histological diagnosis. Conclusions We suggest that the identified molecular patterns play an important role in the pathway of serrated lesion development.

Objective: Recent studies have shown that cancer-associated fibroblasts (CAFs) and the epithelial-mesenchymal transition (EMT) play important roles in the progression and metastasis of CRC. Although prediction of lymph node metastasis in submucosal invasive colorectal cancer (SiCRC) is important, the relationships of CAF and EMT with lymph node metastasis of SiCRC have not yet been examined. Here, we aimed to analyze the expression patterns of CAF- and EMT-related proteins in SiCRC. Materials and Methods: The expression of CAF-related markers, including α-smooth muscle actin, CD10, podoplanin, fibroblast specific protein 1, and adipocyte enhancer-binding protein 1, and EMT-related proteins [zinc finger protein SNAI2 (ZEB1) and twist-related protein 1 (TWIST1) in SiCRC with (n = 29) or without (n = 80) lymph node metastasis was examined by immunohistochemistry. We examined the expression patterns of biomarkers using hierarchical cluster analysis. Consequently, four subgroups were established based on the expression patterns of CAF- and EMT-related markers, and the associations of these subgroups with clinicopathological variables. Results: In multivariate analysis, subgroup 2, which was characterized by high expression of all markers, was correlated with lymph node metastasis (p < 0.01). Next, we examined the associations of individual biomarkers with lymph node metastasis. Multivariate analysis showed that moderately differentiated adenocarcinoma was significantly associated with lymph node metastasis (p < 0.05). Conclusions: Our findings showed that expression patterns of CAF markers and EMT-related proteins may allow for stratification of patients into risk categories for lymph node metastasis in SiCRC.

It is unclear whether somatic copy number alterations (SCNAs) contribute to the development of colorectal cancer (CRC). Here, we aimed to identify the molecular profiles of early colorectal carcinogenesis based on SCNAs and determine the associations of other molecular abnormalities for the detection of neoplasia in both intramucosal neoplasia (IMN) and invasive CRC with invasion into the muscular layer without metastasis (early invasive CRC). A single nucleotide polymorphism array was used to examine 100 colorectal IMNs (low-grade adenoma [LGA], 40; high-grade adenoma [HGA], 25; intramucosal adenocarcinoma [IMA], 35) and early invasive CRC (20 tumors). In addition, genetic mutations (KRAS, BRAF), TP53 overexpression, microsatellite instability (MSI), and DNA methylation (low, intermediate, high) were examined. Hierarchical clustering analysis based on the SCNA pattern was carried out to identify molecular profiles in IMNs and early invasive CRC. Colorectal tumors were classified into three subgroups based on SCNA patterns. Subgroup 1 was characterized by multiple SCNAs, subgroup 3 was closely associated with infrequent SCNAs, and subgroup 2 was an intermediate subgroup in SCNA pattern between subgroups 1 and 3. Although mutations in KRAS were commonly found in all three subgroups, overexpression of TP53 was observed primarily in subgroup 1 and 2. DNA methylation showed a low/intermediate type. Finally, no MSI was detected. Each subgroup was correlated with histology (subgroup 1, early invasive CRC; subgroup 2, LGA; subgroups 2 and 3, HGA and IMA). Considerable SCNAs may be required for acquisition of invasive ability in CRC. Our results provide novel insights into early CRC.

Background We attempted to identify the molecular profiles of gastric intramucosal neoplasia (IMN; low-grade dysplasia, LGD; high-grade dysplasia, HGD; intramucosal cancer, IMC) by assessing somatic copy number alterations (SCNAs) stratified by microsatellite status (microsatellite stable, MSS; microsatellite instable, MSI). Thus, microsatellite status was determined in 84 tumors with MSS status and 16 tumors with MSI status. Methods One hundred differentiated type IMNs were examined using SCNAs. In addition, genetic mutations (KRAS, BRAF, PIK3CA, and TP53) and DNA methylation status (low, intermediate and high) were also analyzed. Finally, we attempted to identify molecular profiles using a hierarchical clustering analysis. Results Three patterns could be categorized according to SCNAs in IMNs with the MSS phenotype: subgroups 1 and 2 showing a high frequency of SCNAs, and subgroup 3 displaying a low frequency of SCNAs (subgroup 1 > 2 > 3 for SCNA). Subgroup 1 could be distinguished from subgroup 2 by the numbers of total SCNAs (gains and losses) and SCN gains (subgroup 1 > 2). The SCNA pattern of LGD was different from that of HGD and IMC. Moreover, IMNs with the MSI phenotype could be categorized into two subtypes: high frequency of SCNAs and low frequency of SCNAs. Genetic mutations and DNA methylation status did not differ among subgroups in IMNs. Conclusion Molecular profiles stratified by SCNAs based on microsatellite status may be useful for elucidation of the mechanisms of early gastric carcinogenesis. Electronic supplementary material The online version of this article (10.1007/s10120-018-0810-5) contains supplementary material, which is available to authorized users.

Ulcerative colitis is a well-known inflammatory bowel disease. Although there are drugs that are effective against this disease, the prevention and attenuation of ulcerative colitis by food rich in functional ingredients without side effects is desired because some drugs have side effects. In this study, we investigated the effects of yuzu (Citrus junos Tanaka), a citrus fruit native to northeast Asia, on a mouse dextran sulfate sodium (DSS)-induced colitis model. Mice given drinking water containing DSS showed significant weight loss, colon shortening, diarrhea, and visible fecal blood. In contrast, mice fed a diet containing 5% yuzu peel for 14 d before receiving DSS showed significant attenuation of these phenotypes. To clarify the mechanism underlying the attenuation, we investigated the anti-inflammatory and antioxidant effects of yuzu peel. We found that yuzu peel extract suppressed tumor necrosis factor-α (TNF-α) production in lipopolysaccharide (LPS)-stimulated mice and murine macrophage cell line through suppression of nuclear factor-κB (NF-κB) activation. In addition, we confirmed that yuzu peel extract had a moderate antioxidant effect. These results suggest that yuzu peel attenuates the pathologies of DSS-induced colitis by coordinately suppressing inflammation and oxidative stress against lipids in vivo.

AIM To examine the association between white opaque substance (WOS) and histologically verified lipid droplets in colorectal epithelial neoplasms. METHODS We reviewed colonoscopy records at our institution from 2014 to 2016 and identified cases of endoscopically or surgically resected colorectal epithelial neoplasms observed by magnifying narrow-band imaging (M-NBI) colonoscopy. Immunohistochemistry was used to stain tumors with a monoclonal antibody specific to adipophilin as a marker of lipids. The expression and distribution of adipophilin were compared between WOS-positive and WOS-negative lesions and among tumors classified by histologic type and depth of invasion. RESULTS Under M-NBI colonoscopy, 81 lesions were positive for WOS and 48 lesions were negative for WOS. The rate of adipophilin expression was significantly higher in WOS-positive lesions (95.1%) than in WOS-negative lesions (68.7%) (P = 0.0001). The incidence of deep adipophilin expression was higher in WOS-positive lesions (24.7%) than in WOS-negative lesions (4.2%) (P = 0.001). The incidence of deep expression was predominant among cancers with massive submucosal invasion (62.5%) compared to adenoma (7.2%) and high-grade dysplasia or cancers with slight submucosal invasion (12.7%) (P = 0.0001). CONCLUSION The distribution of lipid droplets may be closely associated with the visibility of WOS under M-NBI colonoscopy, and with histologic grade and depth of tumor invasion.

To characterize somatic alterations in colorectal cancer (CRC), we conducted a genome-scale analysis of 106 CRC specimens. We assessed comprehensive somatic copy number alterations (SCNAs) in these CRC specimens. In addition, we examined microsatellite instability (MSI; low and high), genetic mutations (KRAS, BRAF, TP53, and PIK3CA), and DNA methylation status (classified into low, intermediate, and high type). We stratified molecular alterations in the CRCs using a hierarchical cluster analysis. The examined CRCs could be categorized into three subgroups using hierarchical cluster analysis. Tumors in subgroup 1 were characterized by a low frequency of SCNAs and a high frequency of MSI-high status, whereas tumors in subgroups 2 and 3 were closely associated with a high frequency of SCNAs. Tumors in subgroup 1 were preferentially present in the right-sided colon and showed frequent MSI-high status. Subgroup 3 was distinguished by specific alterations, including gains at 1q23-44, 1p11-36, 10q11-26, 10p11-13, 12q24-24, and 13q33-33. In contrast, tumors in subgroup 2 were characterized by copy-neutral LOH at 12p12-13, 1q24-25, and 10q22. In addition, KRAS mutations were more frequently found in subgroup 3 than in subgroup 1. TP53 mutations and intermediate levels of DNA methylation were common alterations in the three subgroups. SCNAs contributed to sporadic CRC, and there were three subgroups based on SCNAs that played a different role in driving the development of this disease.

Summary The molecular alterations and pathological features of gastric papillary adenocarcinoma (GPA) remain unknown. We examined GPA samples and compared their molecular and pathological characteristics with those of gastric tubular adenocarcinoma (GTA). Additionally, we identified pathological and molecular features of GPA that vary with microsatellite stability. In the present study, samples from 63 GPA patients and 47 GTA patients were examined using a combination of polymerase chain reaction (PCR)-microsatellite assays and PCR-pyrosequencing in order to detect microsatellite instability (microsatellite instability, MSI; microsatellite stable, MSS), methylation status (low methylation, intermediate methylation and high methylation level), and chromosomal AI in multiple cancer-related loci. Additionally, the expression levels of TP53 and Her2 were evaluated using immunohistochemistry. GTA and GPA are statistically different in their frequency of pathological features, including mucinous, poorly differentiated and invasive micropapillary components. Clear genetic patterns differentiating GPA and GTA could not be identified with a hierarchical cluster analysis, but microsatellite stability was linked with TP53 and Her2 overexpression. Methylation status in GPA was also associated with the development of high microsatellite instability. However, no pathological differences were associated with microsatellite stability. We suggest that although molecular alterations in a subset of GPAs are closely associated with microsatellite stability, they play a minor role in GPA carcinogenesis.

We report an unusual case of mucinous tubular and spindle cell carcinoma (MTSCC) with sarcomatoid change in an 80-year-old Japanese male. In a resected specimen, a grayish-white tumor was found in the left kidney, and several metastases were observed in the right cervical bone and liver. Histologically, most of the main tumor examined showed MTSCC with sarcomatoid change. The transitions between the MTSCC and sarcomatoid components suggested that sarcomatoid transformation had occurred in the MTSCC. Immunohistochemically, the epithelial-mesenchymal transition (EMT)-associated marker ZEB1 was expressed in the sarcomatoid and transitional components. In contrast, ZEB1 expression was negative in the MTSCC component. The present findings support the view that MTSCC with sarcomatoid change represents MTSCC that develops a sarcomatoid component via EMT of the MTSCC component. EMT plays an important role in sarcomatoid change; thus, we conclude that MTSCC with sarcomatoid change is an ‘EMT associated tumor’.

Summary The expression of gastrointestinal differentiation markers is associated with the tumorigenesis and prognosis of digestive cancers. However, little is known about the significance of gastrointestinal differentiation marker profiles in patients with extrahepatic cholangiocarcinoma (CCA), which is classified as perihilar and distal CCA. The purpose of this study was to clarify the role of gastrointestinal differentiation marker expression in extrahepatic CCA based on tumor location. We examined the expression of gastrointestinal differentiation markers in resected perihilar (n = 30) and distal (n = 54) CCAs based on the immunohistochemical expression of the following markers: MUC2, MUC5AC, MUC6, CD10, CDX-2, and cytokeratin 20. Expression scores were determined semiquantitatively based on the rate of positively stained cells. Furthermore, we performed hierarchical clustering of the CCAs based on the immunohistochemical expression scores to evaluate differences in the expression patterns of the 6 gastrointestinal differentiation markers. Consequently, perihilar and distal CCAs were stratified into 2 subgroups each. Among the perihilar CCAs, subgroup 1 was characterized by lower expression of MUC5AC and MUC6, a larger median tumor size, and a significantly worse prognosis compared with subgroup 2. Furthermore, the immunohistological subgroup (subgroup 1 versus 2) and TNM stage (stage III versus II) were independent predictors of patient survival. Among the distal CCAs, subgroup 1 was characterized by lower expression of MUC5AC compared with subgroup 2. We suggest that gastrointestinal differentiation marker profiles are useful for stratifying perihilar and distal CCAs. In addition, gastrointestinal differentiation markers play a crucial role in tumor development, particularly in perihilar CCA.

Ulcerative colitis is a well-known inflammatory bowel disease. Although there are drugs that are effective against this disease, the prevention and attenuation of ulcerative colitis by food rich in functional ingredients without side effects is desired because some drugs have side effects. In this study, we investigated the effects of yuzu (Citrus junos Tanaka), a citrus fruit native to northeast Asia, on a mouse dextran sulfate sodium (DSS)-induced colitis model. Mice given drinking water containing DSS showed significant weight loss, colon shortening, diarrhea, and visible fecal blood. In contrast, mice fed a diet containing 5% yuzu peel for 14 d before receiving DSS showed significant attenuation of these phenotypes. To clarify the mechanism underlying the attenuation, we investigated the anti-inflammatory and antioxidant effects of yuzu peel. We found that yuzu peel extract suppressed tumor necrosis factor-α (TNF-α) production in lipopolysaccharide (LPS)-stimulated mice and murine macrophage cell line through suppression of nuclear factor-κB (NF-κB) activation. In addition, we confirmed that yuzu peel extract had a moderate antioxidant effect. These results suggest that yuzu peel attenuates the pathologies of DSS-induced colitis by coordinately suppressing inflammation and oxidative stress against lipids in vivo.

Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is an inflammatory disease of the central nervous system with a predilection for the hindbrain. Generally, lesions decrease in size with increasing distance from the hindbrain. We herein describe a case of CLIPPERS in a patient showing the largest lesions in the temporal lobe. A 49-year-old man consulted to our hospital with a 22-day history of a high fever and an abnormal visual field involving the left eye. Brain MRI showed a FLAIR hyperintense lesion in the right temporal lobe with punctate gadolinium enhancement. Several days later, lesions showing similar enhancement extended to the pons, medulla oblongata, and cerebellar hemispheres. Biopsy of the right temporal lobe lesion revealed perivascular lymphocytic infiltrates without any findings of demyelination, lymphoma, or glioma. He was diagnosed with CLIPPERS based on clinical, radiological, and histopathological findings. Clinical and radiological findings improved quickly after steroid therapy. CLIPPERS could represent larger lesions distant from the hindbrain showing punctate enhancement.

Background Three-dimensional (3D) spheroids are frequently used in toxicological study because their morphology and function closely resemble those of tissue. As these properties are maintained over a long term, repeated treatment of the spheroids with a test object is possible. Generally, in the repeated treatment test to assess cytotoxicity in the spheroids, ATP assay, colorimetric measurement using pigments or high-content imaging analysis is performed. However, continuous assessment of cytotoxicity in the same spheroids using the above assays or analysis is impossible because the spheroids must be disrupted or killed. To overcome this technical limitation, we constructed a simple monitoring system in which cytotoxicity in the spheroids can be continuously monitored by nondestructive bioluminescence measurement. Results Mouse primary hepatocytes were isolated from transchromosomic (Tc) mice harboring a mouse artificial chromosome (MAC) vector expressing beetle luciferase Emerald Luc (ELuc) under the control of cytomegalovirus immediate early enhancer/chicken β-actin promoter/rabbit β-globin intron II (CAG) promoter, and used in 3D cultures. We confirmed that both luminescence and albumin secretion from the spheroids seeded in the 96-well format Cell-ableTM were maintained for approximately 1 month. Finally, we repetitively treated the luminescent 3D spheroids with representative hepatotoxicants for approximately 1 month, and continuously and nondestructively measured bioluminescence every day. We successfully obtained daily changes of the dose-response bioluminescence curves for the respective toxicants. Conclusions In this study, we constructed a monitoring system in which cytotoxicity in the same 3D spheroids was continuously and sensitively monitored over a long term. Because this system can be easily applied to other cells, such as human primary cells or stem cells, it is expected to serve as the preferred platform for simple and cost-effective long-term monitoring of cellular events, including cytotoxicity. Electronic supplementary material The online version of this article (doi:10.1186/s12896-017-0374-1) contains supplementary material, which is available to authorized users.

Background/study aim Linked color imaging (LCI) by a laser endoscope (Fujifilm Co, Tokyo, Japan) is a novel narrow band light observation. In this study, we aimed to investigate whether LCI could improve the visibility of colorectal polyps using endoscopic videos. Patients and methods We prospectively recorded videos of consecutive polyps 2 – 20 mm in size diagnosed as neoplastic polyps. Three videos, white light (WL), blue laser imaging (BLI)-bright, and LCI, were recorded for each polyp by one expert. After excluding inappropriate videos, all videos were evaluated in random order by two experts and two non-experts according to a published polyp visibility score from four (excellent visibility) to one (poor visibility). Additionally, the relationship between polyp visibility scores in LCI and various clinical characteristics including location, size, histology, morphology, and preparation were analyzed compared to WL and BLI-bright. Results We analyzed 101 colorectal polyps (94 neoplastic) in 66 patients (303 videos). The mean polyp size was 9.0 ± 8.1 mm and 54 polyps were non-polypoid. The mean polyp visibility scores for LCI (2.86 ± 1.08) were significantly higher than for WL and BLI-bright (2.53 ± 1.15, P Conclusions LCI improved polyp visibility compared to WL for both expert and non-expert endoscopists. It is useful for improving polyp visibility in any location, any size, any morphology, any histology, and any preparation level.Study registration: UMIN000013770

Endoscopic findings have now become nearly as detailed as histopathological findings. Thus, one-to-one correspondence and precise feedback of histopathological findings is very desirable but may be very difficult to accomplish. We describe a systematic process called the Kyoto One-to-One Correspondence Method (the KOTO Method) that allows detailed adjustments of endoscopic findings to match histopathological findings. By comparing endoscopic and stereoscopic images of the gastric mucosa, we could obtain one-to-one correspondence between endoscopic images and equivalent histology in 44 of 47 fields. The histological structure of gastric cancers of the same histological subtype may not be similar. One-to-one correspondence between endoscopic images and gastric mucosal histology (histopathology-oriented correspondence) will improve endoscopic diagnosis and provide more useful information for pathological diagnosis.

Backgrounds. Magnifying endoscopy with blue laser imaging (ME-BLI) for diagnosis of early gastric cancer (EGC) is as effective as magnifying endoscopy with narrow-band imaging (ME-NBI). However, there are different EGCs in microstructure visualization between ME-BLI and ME-NBI. This study aimed to clarify the pathological features of the EGCs, in which microstructure visualization was different between ME-NBI and ME-BLI. Methods. EGCs were classified into groups A (irregular microsurface pattern (MSP) in ME-BLI and absent MSP in ME-NBI), B (irregular MSP in two modalities), or C (absent MSP in two modalities), according to the vessel plus surface classification. We compared the pathological features of EGCs between the three groups. Results. 17, four, and five lesions could be evaluated in detail in groups A, B and C, respectively. Well-differentiated adenocarcinomas with shallow crypts were more frequent in group A than in group B (58.8 and 0%, resp.). The mean crypt depth of group A was significantly shallower than that of group B (56 ± 20, 265 ± 64 μm, resp., P=0.0002). Conclusions. ME-BLI could better visualize the microstructures of the EGCs with shallow crypts compared with ME-NBI. Therefore, ME-BLI could enable a more accurate diagnosis of EGC with shallow crypts.

Droplet infiltration (DI) is a tumor infiltration pattern observed in superficial squamous cell carcinoma (SSCC) of the esophagus. Lymph node metastasis (LNM) is related to three reported features of DI (DILFs): longitudinal diameter ≤20 μm (DIsLF); number of constituent cells ≤4 (DInLF); distance from the primary focus ≥200 μm (DIdLF). The aim of this study was to clarify the characteristics of SSCC with high risk of LNM, by analyzing DILF-forming SSCC histopathologically and immunohistochemically. Forty-five SSCC invading the muscularis mucosa or submucosa were divided into two groups with and without above-mentioned three DILFs. The Ki-67 labeling index (LI) and the expression of cytokeratin (CK) 13, 14, 17, and 19 were compared in the paired. The Ki-67 LI was elevated in SSCC with DIsLF and with DInLF (P