Diagnostic utility of DNA integrity number as an indicator of sufficient DNA quality in next-generation sequencing-based genomic profiling.

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.

Dramatic Response to Trastuzumab Deruxtecan Rechallenge in a Patient with HER2-Positive Gastric Cancer: A Case Report.

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.

Complete one-to-one correspondence between magnifying endoscopic and histopathologic images: the KOTO method II.

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.

Analysis of clinicopathological and molecular features of crawling-type gastric adenocarcinoma.

BACKGROUND: Crawling-type adenocarcinoma (CRA) is an important gastric cancer (GC) subtype that exhibits a specific histological pattern and has characteristic clinicopathological findings. Despite its characteristic histology, little is known about the molecular characteristics of CRA. METHODS: We examined 177 GC cases, including 51 cases of CRA and 126 cases having conventional differentiated adenocarcinomas (CDAs). Results for immunohistochemistry (mucin phenotype; Muc5AC, Muc6, Muc2 and CD10, CDX-2, MLH-1, p53 and ß-catenin), mutation analysis (TP53, KRAS and BRAF), microsatellite instability (BAT25, BAT26, D2S123, D5S346 and D17S250), DNA methylation status by a two-panel method (RUNX3, MINT31, LOX, NEUROG1, ELMO1 and THBD), MLH-1 promoter methylation, and allelic imbalance (AI; 1p, 3p, 4p, 5q, 8p, 9p, 13q, TP53, 18q and 22q) were examined. RESULTS: CRAs were more likely to occur in the middle third of the stomach, in younger patients and to be macroscopically depressed. Nuclear accumulation of ß-catenin and loss of MLH-1 expression were less frequent among CRA cases compared to CDA cases. At a molecular level, CRA is often characterized by the deletion mutation c.529_546 (18-base pair deletion at codon 177-182 in exon 5) in the TP53 gene (10 cases). Although the low methylation epigenotype was significantly more frequent for CRAs compared to CDAs, multiple AIs were more often seen in CRAs relative to CDAs. CONCLUSIONS: The results demonstrated that TP53 mutations, particularly c.529_546del, and multiple AIs are closely associated with CRA carcinogenesis. Our results suggest that CRA is an independent entity of GC in terms of clinicopathologic and molecular findings.

Dysregulation of microRNA expression during the progression of colorectal tumors.

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.

The clinicopathological and molecular features of sporadic gastric foveolar type neoplasia.

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, ß-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 ß-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.

Diagnostic algorithm of magnifying endoscopy with crystal violet staining for non-ampullary duodenal epithelial tumors.

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.

Clinicopathological and Molecular Findings of Differentiated-Type Minute Gastric Intramucosal Neoplasia.

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 ß-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 ß-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 ß-catenin were closely associated with tumor development from MIMN to non-MIMN.

Risk Factors for Post-gastric Endoscopic Submucosal Dissection Bleeding with a Special Emphasis on Anticoagulant Therapy.

BACKGROUND: Little is known about the risk factors for post endoscopic submucosal dissection (post-ESD) bleeding with anticoagulant therapy. AIMS: We aimed to investigate the risk factors for post-ESD bleeding for early gastric cancer (EGC) with an emphasis on anticoagulant therapy. METHODS: 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. RESULTS: 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. CONCLUSIONS: Anticoagulant therapy and resected specimen size were risk factors associated with post-ESD bleeding for EGC.

Differential expression of microRNAs in colorectal cancer: Different patterns between isolated cancer gland and stromal cells.

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.

Microvascular density under magnifying narrow-band imaging endoscopy in colorectal epithelial neoplasms.

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.

The expression of gastrointestinal differentiation markers in extrahepatic cholangiocarcinoma: clinicopathological significance based on tumor location.

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.

Gastric mixed neuroendocrine-non-neuroendocrine neoplasm (MiNEN) with pancreatic acinar differentiation: a case report.

BACKGROUND: Gastric mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs) are infrequently encountered in routine practice. Some gastric neuroendocrine carcinomas (NECs) have a variety of differentiation patterns; however, pancreatic acinar differentiation in gastric NECs is rare. The molecular abnormalities of NECs with pancreatic acinar differentiation are not well understood. CASE PRESENTATION: A 67-year-old male with a gastric MiNEN with pancreatic acinar differentiation without any symptoms. The tumor consisted of two components, including both glandular and solid histological features. Although the former component was a common type of adenocarcinoma, the latter showed endocrine differentiation and expressed pancreatic acinar enzymes immunohistochemically. A positive signal with the anti-BCL10 antibody, which detects one of the pancreatic acinar enzymes, was also present specifically in the latter component. We also examined TP53 genomic mutations, DNA methylation status, and allelic imbalance (AI), which is an indicator of tumor aggressiveness. Although both components of this tumor showed no genomic mutation and a low methylation epigenotype, the frequency of AI was higher in the acinar-endocrine component than in the adenocarcinomatous component. The finding of AI indicated the progression of the conventional adenocarcinoma to an acinar-endocrine component and identified the aggressive potential of the acinar-endocrine component. CONCLUSIONS: We report a rare case of gastric MiNEN with pancreatic acinar differentiation. AI analysis revealed tumor progression and aggressiveness. In addition, the usefulness of the anti-BCL10 antibody for detecting the acinar-endocrine component was suggested.

Mesenteric extraovarian Sertoli-Leydig cell tumor without DICER1 hotspot mutation: a case report.

BACKGROUND: Ovarian Sertoli-Leydig cell tumors (SLCTs) with androgenic manifestations harbor DICER1 mutations in 30-60% of cases. Ovarian SLCTs without DICER1 hotspot mutations have been reported to exhibit elderly onset and no androgenic manifestations. We present the first case of a primary mesenteric SLCT without DICER1 hotspot mutation. CASE PRESENTATION: An 84-year-old woman presented with a 75-mm mesenteric solid tumor. She presented no androgenic or estrogenic manifestations. She underwent ileocecal resection. Histologically, her mesenteric tumor showed histopathological features that resembled moderately differentiated SLCT. Moreover, DICER1 hotspot mutation was not detected. CONCLUSIONS: We described the first case of heterotopic primary mesenteric SLCT without DICER1 hotspot mutation.

Sarcomatoid change associated with epithelial-mesenchymal transition in mucinous tubular and spindle cell carcinoma of the kidney: a case report.

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'.

Clinical and Pathological Challenges in the Diagnosis of Gastric-Type Differentiated Adenocarcinoma in the Stomach: A Study of Endoscopic Submucosal Dissection Cases.

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.

Long-term outcomes and prognostic factors with non-curative endoscopic submucosal dissection for gastric cancer in elderly patients aged ≥ 75 years.

BACKGROUND: 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. METHODS: 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. RESULTS: 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 < 44.8, distal tumor location and macroscopically depressed or flat configuration were associated with poor OS. Cox multivariate analysis revealed high CCI (≥ 3) to be an independent prognostic factor associated with OS (hazard ratio: 2.63, 95% confidence interval [CI] 1.06-6.49, P = 0.037). CONCLUSIONS: CCI may be a useful parameter for decision-making regarding additional surgery for elderly patients with gastric cancer treated by non-curative ESD.

Analysis of the expression of cancer-associated fibroblast- and EMT-related proteins in submucosal invasive colorectal cancer.

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.

Molecular Profiling Based on KRAS/BRAF Mutation, Methylation, and Microsatellite Statuses in Serrated Lesions.

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.