Clinical usefulness and acceptability of small-bowel capsule endoscopy with panoramic imaging compared with axial imaging in Japanese patients.

Objectives: We aimed to evaluate the usefulness and acceptability of CapsoCam Plus (CapsoCam) in Japanese patients. Methods: This retrospective single-center study enrolled 930 patients with suspected small-bowel bleeding (SSBB) who underwent capsule endoscopy. Thirty-three patients using CapsoCam and PillCam SB3 (SB3) were matched using propensity score matching. The diagnostic yield and the acceptability of CapsoCam were evaluated. Results: There was no SSBB case where capsule endoscopy was performed within 48 h of bleeding. CapsoCam had a significantly higher observation rate of the entire small bowel (97% vs. 73%, p = 0.006) and Vater's papilla (82% vs. 15%, p < 0.001) than SB3. The reading time of CapsoCam was significantly longer than that of SB3 (30 vs. 25 min, p < 0.001), and CapsoCam's time from the capsule endoscopy swallowing to read completion was longer than that of SB3 (37 vs. 12 h, p < 0.001). The two groups showed no difference in the capsule endoscopy findings according to the P classification. Notably, 85% of the patients using CapsoCam reported examination distress as "not at all" or "almost not," and 94% reported swallowing difficulty as "very easy" or "easy." Conclusions: CapsoCam took time to read; however, it is a well-tolerated examination with a high observation rate of Vater's papilla and entire small-bowel mucosa. Detectability of bleeding sources was comparable in both modalities for cases of occult SSBB and overt SSBB more than 48 h after bleeding. CapsoCam is a useful modality for patients with SSBB.

Management of T1 colorectal cancer.

BACKGROUND: Approximately 10% of patients with submucosal invasive (T1) colorectal cancer (CRC) have lymph node metastasis (LNM). The risk of LNM can be stratified according to various histopathological factors, such as invasion depth, lymphovascular invasion, histological grade, and tumor budding. SUMMARY: T1 CRC with a low risk of LNM can be cured by local excision via endoscopic resection (ER), whereas surgical resection (SR) with lymph node dissection is required for high-risk T1 CRC. Current guidelines raise concern that many patients receive unnecessary SR, even though most patients achieve a radical cure. Novel diagnostic techniques for LNM, such as nomograms, artificial intelligence systems, and genomic analysis, have been recently developed to identify more low-risk T1 CRC cases. Assessing the curability and the necessity of additional treatment, including SR with lymph node dissection and chemoradiotherapy, according to histopathological findings of the specimens resected using ER, is becoming an acceptable strategy for T1 CRC, particularly for rectal cancer. Therefore, complete resection with negative vertical and horizontal margins is necessary for this strategy. Advanced ER methods for resecting the muscle layer or full thickness, which may guarantee complete resection with negative vertical margins, have been developed. KEY MESSAGE: Although a necessary SR should not be delayed for T1 CRC given its unfavorable prognosis when SR with lymph node dissection is performed, the optimal treatment method should be chosen based on the risk of LNM and the patient's life expectancy, physical condition, social characteristics, and wishes.

Significance of changes in tumor markers in patients treated with durvalumab plus tremelimumab combination therapy as a surrogate marker for tumor response to unresectable hepatocellular carcinoma.

AIM: When evaluating response to immune checkpoint inhibitor therapy, the tumor sometimes initially swells before shrinking and ultimately responding, also called pseudo-progression. In this study, we analyzed whether tumor markers were useful for reflecting the treatment response. METHODS: Thirty-three patients who were treated with durvalumab plus tremelimumab combination therapy (Dur + Tre) were enrolled. Their functional reserve was Child-Pugh grade A. Their tumor markers α-fetoprotein (AFP), des-γ-carboxy prothrombin (DCP), or AFP-Lectin 3 fraction (AFP-L3) were positive. Tumor markers were evaluated before treatment and at 1, 4, and 8 weeks after the start of treatment. The first radiological evaluation was carried out at 4 weeks and the second evaluation at 8-12 weeks. The responders included those with complete response and partial response and the nonresponders included those with stable disease (SD) and progression disease at best response evaluated by Response Evaluation Criteria in Solid Tumors. RESULTS: In the responder group, the change ratio of AFP, DCP, and AFP-L3 specifically decreased at 8 weeks. In the nonresponder group, the change ratio of DCP specifically increased at 4 weeks. The optimal cut-off value to divide responders and nonresponders at 4 weeks was approximately -40%. The ratio of responders was 72.7% in the patients whose AFP or DCP decreased over 40% at 4 weeks. CONCLUSIONS: The change in tumor markers is a more useful predicter of tumor response to Dur + Tre than imaging evaluation alone.

Vertical margin distance in T1 colorectal carcinoma resected by endoscopic submucosal dissection affects prognosis after additional surgery.

PURPOSE : A vertical margin (VM) distance of < 500 µm is a risk factor for recurrence in patients with T1 colorectal carcinoma (CRC) resected by endoscopy. We aimed to determine the effects of the VM distance on the recurrence and prognosis of T1 CRC. METHODS: We enrolled 168 patients with T1 CRC who underwent additional surgery after endoscopic submucosal dissection (ESD) at multiple centers between 2008 and 2016. None of the patients were followed up for < 5 years. The enrolled 168 patients were classified into patients with VM distance of < 500 µm including positive VM (n = 72 [43%], VM distance < 500 µm group) and patients with VM distance of ≥ 500 µm (n = 96 [57%], VM distance ≥ 500 µm group). The clinicopathological features, recurrence rates, and prognoses were compared between the groups using propensity-score matching (PSM). RESULTS: Tumors recurred in eight of the 168 patients (5%) with VM distance < 500 µm. After PSM, the rate of overall recurrence and local recurrence in the VM distance < 500 µm group were significantly higher than those in the VM distance ≥ 500 µm group. The 5-year recurrence-free survival rate was significantly higher in the VM distance ≥ 500 µm group than that in VM distance < 500 µm group after PSM (100% vs. 89%, p < 0.012). CONCLUSIONS: Complete en bloc resection of T1 CRC via ESD must include a sufficient amount of SM to reduce the risk of metastasis and recurrence after additional surgery.

Impact of endoscopic ultrasound-guided fine needle aspiration on positive peritoneal lavage cytology in patients with resectable pancreatic body and tail cancer.

BACKGROUND/PURPOSE: A recent study has demonstrated that the timing of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) significantly influences the peritoneal lavage cytology (CY) outcomes in pancreatic body-tail cancer. The aim of this study was to clarify the impact of EUS-FNA on CY positivity in patients with resectable pancreatic body-tail cancer. METHODS: Patients with anatomically resectable pancreatic body-tail cancer surgically resected at Hiroshima University Hospital were enrolled, and elated clinicopathological factors, including EUS-FNA variables and CY positivity rate, were analyzed. RESULTS: Of the 129 eligible patients, 16 (12%) had positive CY. The EUS-FNA rates of the CY-positive and CY-negative groups were not significantly different (63% vs. 52%, p = .440). Multivariate analysis revealed that lymph node metastasis was the only independent risk factor for CY positivity (odds ratio: 5.734, p = .031). A total of 10 (14%) of the 69 patients who underwent EUS-FNA had positive CY; however, needle specifications and the interval between EUS-FNA and CY examination did not differ between the CY-positive and CY-negative groups. CY positivity rates were comparable for intervals ≤14 days and ≥15 days (17% vs. 14%, p = 1.000). CONCLUSIONS: EUS-FNA may not affect CY positivity in patients with resectable pancreatic body-tail cancer, regardless of the timing.

Endoscopic Retrograde Cholangiopancreatography-Related Procedures for the Differential Diagnosis of Isolated Immunoglobin G4-Related Sclerosing Cholangitis and Perihilar Cholangiocarcinoma.

BACKGROUND/PURPOSE: Differential diagnosis of isolated immunoglobin (Ig)G4-related sclerosing cholangitis (IgG4-SC) and cholangiocarcinoma is challenging. We aimed to clarify the role of endoscopic retrograde cholangiography (ERCP)-related procedures in the differential diagnosis of isolated IgG4-SC and perihilar cholangiocarcinoma (PHCC). METHODS: Seven patients with hilar-type isolated IgG4-SC diagnosed at Hiroshima University Hospital and sixty-five patients with surgically resected invasive PHCC were enrolled, and the diagnostic yields of intraductal ultrasonography (IDUS), peroral cholangioscopy (POCS), and pathological examinations were determined. RESULTS: In six of seven (86%) patients with isolated IgG4-SC, the stricture was in the perihilar bile duct. IDUS showed that symmetrical wall thickening (40% vs. 5%, p = 0.04), homogeneous internal echo (80% vs. 5%, p < 0.001), and smooth outer margins (80% vs. 6%, p < 0.001) were more frequent in isolated IgG4-SC than in PHCC. POCS showed a smooth mucosal surface more frequent in isolated IgG4-SC (75% vs. 7%, p = 0.006). Only one patient had two pathological findings characteristic of IgG4-SC. The sensitivity for diagnosing PHCC was 81% using two or more combined sampling methods. CONCLUSIONS: Pathological examinations have limitations in the differential diagnosis of isolated-IgG4-SC and PHCC, and a diagnostic strategy that combines multiple ERCP-related procedures, including IDUS and POCS, is recommended.

Interferon alpha induces a stronger antiviral effect than interferon lambda in HBV/HDV infected humanized mice.

Recent studies indicate that treatment of chronic hepatitis D virus (HDV) with either pegylated interferon (IFN)λ or pegylated IFNα monotherapy leads to a dramatic decline in HDV RNA. Herein, we investigated the innate antiviral efficacy of IFNλ and IFNα in humanized mice that lack an adaptive immune response. Humanized mice were either co-infected with hepatitis B virus (HBV) and HDV simultaneously, or HDV infection was performed subsequent to HBV infection (i.e., superinfected). After steady viral replication was achieved, mice received either IFNλ (n=6) or IFNα (n=7) for 12 (or 13) weeks. Pretreatment median levels of serum HBV DNA (8.8 [IQR:0.2] log IU/ml), HDV RNA (9.8 [0.5] log IU/ml), HBsAg (4.0 [0.4] log IU/ml) and human albumin, hAlb (6.9 [0.1] log ng/mL) were similar between mice treated with IFNα or IFNλ and between those coinfected versus superinfected. Compared to mice treated with IFNλ, mice treated with IFNα had a significantly greater decline in HBV, HDV, and HBsAg levels. In conclusion, IFNα induces stronger inhibition of HBV and HDV than IFNλ in humanized mice that lack an adaptive immune response. Further studies are needed to assess the respective role of the combined innate-and adaptive-immune systems in the treatment of HBV and HDV with IFNα and IFNλ.

Severe Refractory Diarrhea Associated with COVID-19: A Case Report.

Introduction: Coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is frequently associated with various gastrointestinal symptoms, including abdominal pain, vomiting, and diarrhea. Moreover, several cases of refractory diarrhea have been reported after COVID-19 recovery. Herein, we present a case of severe refractory diarrhea associated with COVID-19. Case Presentation: A 50-year-old man with no comorbidities was admitted to our hospital with SARS-CoV-2 pneumonia. His respiratory status deteriorated, and ventilatory management, including extracorporeal membrane oxygenation, was needed. The patient's respiratory condition improved, resulting in a transfer to another hospital for rehabilitation. However, the patient developed diarrhea that worsened to 6,000-7,000 mL/day, and he was transferred to our hospital. We diagnosed the patient with enterocolitis caused by cytomegalovirus infection and treated him with ganciclovir on day 5 after transfer to our hospital. The diarrhea did not improve. We suspected enterocolitis associated with COVID-19 and administered a methylprednisolone pulse (intravenous injection, 1,000 mg/day for 3 days) on day 10 after transfer, resulting in a marked improvement in his symptoms. The prednisolone dose was tapered, and no recurrence of diarrhea was observed thereafter. Conclusion: The prevalence of COVID-19-associated enterocolitis is low, and the pathogenesis of the disease remains unclear. Prednisolone administration should be considered in cases of post-COVID-19 symptoms of severe diarrhea due to a possible abnormal immune response related to COVID-19.

Two Cases of Increased Gastrointestinal Polyps in Familial Adenomatous Polyposis following Antiacid Agent Intake.

Introduction: Familial adenomatous polyposis (FAP), a hereditary disorder of the gastrointestinal tract, is an autosomal dominant inherited condition caused by germline mutations in the adenomatous polyposis coli (APC) gene. It is characterized by the development of hundreds to thousands of colorectal adenomatous polyps, which, if left untreated, can eventually develop into colorectal carcinomas. Representative extracolonic tumors in FAP include multiple duodenal adenomas and desmoid tumors. Moreover, multiple fundic gland polyps are frequently identified in the stomachs of patients with FAP. Case Presentation: Herein, we report the two cases. A 52-year-old woman who underwent total colectomy for FAP, and pancreatoduodenectomy was initiated on esomeprazole for the treatment of anastomotic erosion. Esophagogastroduodenoscopy performed 42 months later showed an increased number and size of gastric fundic gland polyps, which subsequently decreased after replacing esomeprazole with ranitidine. Similarly, a 39-year-old woman with FAP was initiated on vonoprazan for the treatment of reflux symptoms. Esophagogastroduodenoscopy and colonoscopy performed 14 months later indicated an increase in the number of gastric fundic gland polyps and colorectal polyps, which subsequently decreased after vonoprazan discontinuation. In these two cases, the increase and decrease in the number and size of fundic gland polyps and colon adenoma were associated with serum gastrin levels. Conclusion: Gastric fundic gland polyps and colon polyps may rapidly increase in number and size due to increased gastrin levels induced by proton pump inhibitor/potassium-competitive acid blocker use. Hence, these drugs should be prescribed with caution.

Discovering cancer stem-like molecule, nuclear factor I X, using spatial transcriptome in gastric cancer.

Gastric cancer (GC) is characterized by significant intratumoral heterogeneity, and stem cells are promising therapeutic targets. Despite advancements in spatial transcriptome analyses, unexplored targets for addressing cancer stemness remain unknown. This study aimed to identify Nuclear Factor IX (NFIX) as a critical regulator of cancer stemness in GC and evaluate its clinicopathological significance and function. Spatial transcriptome analysis of GC was conducted. The correlation between NFIX expression, clinicopathological factors, and prognosis was assessed using immunostaining in 127 GC cases. Functional analyses of cancer cell lines validated these findings. Spatial transcriptome analysis stratified GC tissues based on genetic profiles, identified CSC-like cells, and further refined the classification to identify and highlight the significance of NFIX, as validated by Monocle 3 and CytoTRACE analyses. Knockdown experiments in cancer cell lines have demonstrated the involvement of NFIX in cancer cell proliferation and kinase activity. This study underscores the role of spatial transcriptome analysis in refining GC tissue classification and identifying therapeutic targets, highlighting NFIX as a pivotal factor. NFIX expression is correlated with poor prognosis and drives GC progression, suggesting its potential as a novel therapeutic target for personalized GC therapies.

The Spatial Extracellular Proteomic Tumor Microenvironment Distinguishes Molecular Subtypes of Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) mortality rates continue to increase faster than those of other cancer types due to high heterogeneity, which limits diagnosis and treatment. Pathological and molecular subtyping have identified that HCC tumors with poor outcomes are characterized by intratumoral collagenous accumulation. However, the translational and post-translational regulation of tumor collagen, which is critical to the outcome, remains largely unknown. Here, we investigate the spatial extracellular proteome to understand the differences associated with HCC tumors defined by Hoshida transcriptomic subtypes of poor outcome (Subtype 1; S1; n = 12) and better outcome (Subtype 3; S3; n = 24) that show differential stroma-regulated pathways. Collagen-targeted mass spectrometry imaging (MSI) with the same-tissue reference libraries, built from untargeted and targeted LC-MS/MS was used to spatially define the extracellular microenvironment from clinically-characterized, formalin-fixed, paraffin-embedded tissue sections. Collagen α-1(I) chain domains for discoidin-domain receptor and integrin binding showed distinctive spatial distribution within the tumor microenvironment. Hydroxylated proline (HYP)-containing peptides from the triple helical regions of fibrillar collagens distinguished S1 from S3 tumors. Exploratory machine learning on multiple peptides extracted from the tumor regions could distinguish S1 and S3 tumors (with an area under the receiver operating curve of ≥0.98; 95% confidence intervals between 0.976 and 1.00; and accuracies above 94%). An overall finding was that the extracellular microenvironment has a high potential to predict clinically relevant outcomes in HCC.

Pexidartinib and Immune Checkpoint Inhibitors Combine to Activate Tumor Immunity in a Murine Colorectal Cancer Model by Depleting M2 Macrophages Differentiated by Cancer-Associated Fibroblasts.

Tumor-associated macrophages (TAMs) and cancer-associated fibroblasts (CAFs) are known to play supportive roles in tumor development and progression, but their interactions in colorectal cancer (CRC) remain unclear. Here, we investigated the effects of colon-cancer-derived CAFs on TAM differentiation, migration, and tumor immunity, both in vitro and in vivo. When co-cultured with monocytes, CAFs attracted monocytes and induced their differentiation into M2 macrophages. Immunohistology of surgically resected human CRC specimens and orthotopically transplanted mouse tumors revealed a correlation between numbers of CAFs and numbers of M2 macrophages. In a mouse model of CRC orthotopic transplantation, treatment with an inhibitor of the colony-stimulating factor-1 receptor (PLX3397) depleted M2 macrophages and increased CD8-positive T cells infiltrating the tumor nest. While this treatment had a minor effect on tumor growth, combining PLX3397 with anti-PD-1 antibody significantly reduced tumor growth. RNA-seq following combination therapy showed activation of tumor immunity. In summary, CAFs are involved in the induction and mobilization of M2 macrophage differentiation in the CRC tumor immune microenvironment, and the combination of cancer immunotherapy and PLX3397 may represent a novel therapeutic option for CRC.

Integrator complex subunit 6 promotes hepatocellular steatosis via ß-catenin-PPARγ axis.

Hepatic adipogenesis has common mechanisms with adipocyte differentiation such as PPARγ involvement and the induction of adipose tissue-specific molecules. A previous report demonstrated that integrator complex subunit 6 (INTS6) is required for adipocyte differentiation. This study aimed to investigate INTS6 expression and its role in hepatic steatosis progression. The expression of INTS6 and PPARγ was examined in the liver of a mouse model of steatohepatitis and in paired liver biopsy samples from 11 patients with severe obesity and histologically proven metabolic dysfunction associated steatohepatitis (MASH) before and one year after bariatric surgery. To induce hepatocellular steatosis in vitro, an immortalized human hepatocyte cell line Hc3716 was treated with free fatty acids. In the steatohepatitis mouse model, we observed hepatic induction of INTS6, PPARγ, and adipocyte-specific genes. In contrast, ß-catenin which negatively regulates PPARγ was reduced. Biopsied human livers demonstrated a strong positive correlation (r2 = 0.8755) between INTS6 and PPARγ mRNA levels. After bariatric surgery, gene expressions of PPARγ, FABP4, and CD36 were mostly downregulated. In our in vitro experiments, we observed a concentration-dependent increase in Oil Red O staining in Hc3716 cells after treatment with the free fatty acids. Alongside this change, the expression of INTS6, PPARγ, and adipocyte-specific genes was induced. INTS6 knockdown using siRNA significantly suppressed cellular lipid accumulation together with induction of ß-catenin and PPARγ downregulation. Collectively, INTS6 expression closely correlates with PPARγ. INTS6 suppression significantly reduced hepatocyte steatosis via ß-catenin-PPARγ axis, indicating that INTS6 could be a novel therapeutic target for treating MASH.

Long-Term Outcomes of Additional Surgery After Endoscopic Resection Versus Primary Surgery for T1 Colorectal Cancer.

INTRODUCTION: There is considerable concern about whether endoscopic resection (ER) before additional surgery (AS) for T1 colorectal cancer (CRC) has oncologically potential adverse effects. Therefore, the aim of this study was to compare the long-term outcomes, including overall survival (OS), of patients treated with AS after ER vs primary surgery (PS) for T1 CRC using a propensity score-matched analysis from a large observational study. METHODS: This study investigated 6,105 patients with T1 CRC treated with either ER or surgical resection between 2009 and 2016 at 27 high-volume Japanese institutions, with those undergoing surgery alone included in the PS group and those undergoing AS after ER included in the AS group. Propensity score matching was used for long-term outcomes of mortality and recurrence analysis. RESULTS: After propensity score matching, 1,219 of 2,438 patients were identified in each group. The 5-year OS rates in the AS and PS groups were 97.1% and 96.0%, respectively (hazard ratio: 0.72, 95% confidence interval: 0.49-1.08), indicating the noninferiority of the AS group. Moreover, 32 patients (2.6%) in the AS group and 24 (2.0%) in the PS group had recurrences, with no significant difference between the 2 groups (odds ratio: 1.34, 95% confidence interval: 0.76-2.40, P = 0.344). DISCUSSION: ER before AS for T1 CRC had no adverse effect on patients' long-term outcomes, including the 5-year OS rate. ER is a viable first-line treatment option for endoscopically resectable T1 CRC.

Ramucirumab for advanced hepatocellular carcinoma in the current real world: a Japanese single-arm study post-REACH-2 (The R-evolution study).

This study aimed to complement the results of the REACH-2 study by prospectively evaluating the safety and efficacy of ramucirumab in advanced hepatocellular carcinoma (HCC) in a real-world setting. This was an open-label, nonrandomized, multicenter, prospective study conducted at 13 institutions in Japan (jRCTs031190236). The study included Child-Pugh Class A patients with advanced HCC who had received pretreatment with atezolizumab plus bevacizumab (Atez/Bev) or lenvatinib. Ramucirumab was introduced as a second-line treatment after Atez/Bev or lenvatinib and as a third-line treatment after Atez/Bev and lenvatinib. Between May 2020 and July 2022, we enrolled 19 patients, including 17 who received ramucirumab. Additionally, seven patients received lenvatinib, another seven patients received Atez/Bev, and three patients received Atez/Bev followed by lenvatinib as prior treatment. The primary endpoint was a 6-month progression-free survival (PFS) rate, which was 14.3%. The median PFS and overall survival were 3.7 and 12.0 months, respectively. The most common grade ≥ 3 adverse events (AEs) were hypertension (23.5%), proteinuria (17.6%), and neutropenia (11.8%). The discontinuation rate due to AEs was 29.4%. Six patients progressed from Child-Pugh A to B after treatment with ramucirumab. Thirteen patients were eligible for post-ramucirumab treatment, including systemic therapy. Despite the limited number of patients, the efficacy of ramucirumab was comparable to that observed in the REACH-2 study when used after lenvatinib and Atez/Bev. However, the incidence of AEs was higher than that in the REACH-2 study.

Long-term prognosis after endoscopic submucosal dissection for esophageal cancer in older adult patients.

BACKGROUND: The validity of endoscopic submucosal dissection (ESD) for esophageal squamous cell carcinoma (ESCC) in older individuals with comorbidities remains unclear. Therefore, this study evaluated the safety and efficacy of ESD and additional treatment for ESCC in older adult patients. METHODS: The clinicopathological characteristics and clinical outcomes of 398 consecutive older adult patients (≥ 65 years) with 505 lesions who underwent ESD for ESCC at the Hiroshima University Hospital between September 2007 and December 2019 were retrospectively evaluated. Additionally, the prognoses of 381 patients who were followed up for > 3 years were assessed. RESULTS: The mean patient age and procedure time were 73.1 ± 5.8 years and 77.1 ± 43.5 min, respectively. The histological en bloc resection rate was 98% (496/505). Postoperative stenosis, perforation, pneumonia, and delayed bleeding were conservatively treated in 82 (16%), 19 (4%), 15 (3%), and 5 (1%) patients, respectively. The 5-year overall and disease-specific survival rates were 78.9% and 98.0%, respectively (mean follow-up time: 71.1 ± 37.3 months). Multivariate analysis showed that age and the American Society of Anesthesiologists classification of physical status class ≥III (hazard ratio: 1.27; 95% confidence interval: 1.01-1.59, p = 0.0392) were independently associated with overall survival. A significantly lower overall survival rate was observed in the high-risk follow-up group than in the low-risk follow-up and high-risk additional treatment groups (p < 0.01). However, no significant difference in disease-specific survival was observed among the three groups. CONCLUSIONS: ESD is safe for ESCC treatment in patients aged ≥ 65 years. However, additional treatments should be considered based on the patient's general condition.

Mixed neuroendocrine-non-neuroendocrine neoplasm of the bile duct with long-term prognosis after neoadjuvant chemotherapy.

A 74-year-old man with obstructive jaundice presented with a thickened distal bile duct wall. A transpapillary forceps biopsy revealed an adenocarcinoma; however, because the tumor image was different from that of a typical cholangiocarcinoma, endoscopic ultrasound-guided fine-needle aspiration was performed on the tumor and enlarged lymph nodes. The tumor cells were positive for synaptophysin and CD56 with a Ki67 labeling index of 95%, and he was diagnosed with small cell neuroendocrine carcinoma. We diagnosed a bile duct tumor with neuroendocrine carcinoma component with lymph node metastasis. Preoperative chemotherapy for neuroendocrine carcinoma was administered because R0 resection was difficult and the risk of postoperative recurrence was high. Three courses of chemotherapy with carboplatin and etoposide resulted in marked tumor shrinkage, and radical resection was performed 3 months after diagnosis. Postoperative pathology revealed adenocarcinoma in the mucosal epithelium and small cell neuroendocrine carcinoma in the submucosa, most of which resolved with chemotherapy. Carboplatin and etoposide were resumed as adjuvant chemotherapy, and 67 months of recurrence-free survival were achieved after surgery.

Influence of dispersion slope on the diagnosis of liver fibrosis by the shear wave in metabolic dysfunction-associated steatotic liver disease.

AIM: Shear wave (SW) elastography is used to evaluate metabolic dysfunction-associated steatotic liver disease (MASLD) pathophysiology. Increased elasticity due to fibrosis and increased viscosity due to necrosis and inflammation affect SW. Assessing fibrosis, the most prognostically relevant pathology, is critical. Viscosity is evaluated using the dispersion slope (DS); however, cut-off values that affect SW values are unclear. We compared the ultrasound imaging parameters (SW for viscoelasticity; DS for viscosity) with pathological findings. METHODS: Patients (n = 159) who underwent liver biopsy and SW and DS assessments at our hospital were included. Fibrosis stage and inflammation grade cut-off values were calculated from SW, DS, and liver biopsy results using receiver operating characteristic curves. Cases in which liver biopsy results were inconsistent with SW results were used to determine the effect of viscosity on SW values. DS was examined in the Correct and Incorrect Diagnosis groups, which were categorized based on the concordance between SW and liver biopsy results. Dispersion slope cut-off values between the two groups were calculated. RESULTS: Fibrosis stage cut-off values by SW (m/s) were: ≥F2, 1.62; ≥F3, 1.74; and F4, 1.97. Inflammation grade cut-off values by DS (m/s/kHz) were: ≥A1, 11.6; ≥A2, 14.5; and A3, 16.1. The Correct/Incorrect Diagnosis groups had 25/70 patients. The DS cut-off value for both groups was 13.2 m/s/kHz. CONCLUSIONS: Shear wave and DS are useful for evaluating liver fibrosis and inflammation in MASLD. For DS > 13.2 m/s/kHz, SW may be affected by the increased viscosity owing to inflammation. In such patients, caution should be used when determining/interpreting values.

Analysis of anti-tumor effect and mechanism of GLS1 inhibitor CB-839 in colorectal cancer using a stroma-abundant tumor model.

BACKGROUND: Glutaminase 1 (GLS1), a key enzyme in glutamine metabolism in cancer cells, acts as a tumor promoter and could be a potential therapeutic target. CB-839, a GLS1-specific inhibitor, was developed recently. Herein, we aimed to elucidate the anti-tumor effects and mechanism of action of CB-839 in colorectal cancer (CRC). METHODS: Using the UCSC Xena public database, we evaluated GLS1 expression in various cancers. Immunostaining for GLS1 was performed on 154 surgically resected human CRC specimens. Subsequently, we examined the GLS1 mRNA expression levels in eight CRC cell lines and evaluated the association between GLS1 expression and CB-839 efficacy. To create a reproducible CRC model with abundant stroma and an allogeneic immune response, we co-transplanted CT26 and stem cells into BALB/c mice and treated them with CB-839. Finally, RNA sequencing of mouse tumors was performed. RESULTS: Database analysis showed higher GLS1 expression in CRC tissues than in normal colon tissues. Clinical samples from 114 of the 154 patients with CRC showed positive GLS1 expression. GLS1 expression in clinical CRC tissues correlated with vascular invasion. CB-839 treatment inhibited cancer cell proliferation depending on GLS1 expression in vitro and inhibited tumor growth and metastasis in the CRC mouse model. RNA sequencing revealed that CB-839 treatment inhibited stromal activation, tumor growth, migration, and angiogenesis. These findings were validated through in vitro and in vivo experiments and clinical specimen analysis. CONCLUSIONS: GLS1 expression in CRC plays important roles in tumor progression. CB-839 has inhibitory effects on cancer proliferation and the tumor microenvironment.