廣岡 芳樹

BACKGROUND: With recent advances in chemotherapy for unresectable pancreatic ductal adenocarcinoma (PDAC) with liver metastasis (LM), attempts have been made to resect the primary tumor in patients showing favorable responses to anti-cancer treatment (so-called "conversion surgery"; CS). This study aimed to clarify the outcomes of CS for PDAC with LM in a nationwide multicenter study. METHODS: This retrospective, multicenter study was conducted as a project study of the Japan Pancreas Society and included patients with PDAC with LM at initial diagnosis, diagnosed radiologically or intraoperatively (occult LM), who underwent CS after at least 4 months of chemotherapy between 2010 and 2022. Survival outcomes and prognostic factors were analyzed. RESULTS: 90 patients were enrolled from 31 Japanese institutions. Median duration of preoperative chemotherapy was 10.4 (range, 4.2-58.5) months, and gemcitabine plus nab-paclitaxel was the most common first-line regimen, followed by folinic acid, 5-fluorouracil, irinotecan, and oxaliplatin. Liver metastasectomy was performed in 27 patients (30%). 82 patients (91.1%) initiated adjuvant chemotherapy, and 41 (45.6%) completed it. Overall survival (OS) from initial treatment was 53.1 (95% CI 41.6-65.7) months; OS after CS was 39.7 (95% CI 24.4-55.9) months, and disease-free survival was 14.7 (95% CI 9.3-23.4) months. Preoperative normalization of carbohydrate antigen 19-9 and pathologic negative lymph node metastasis were independent prognostic factors for OS. CONCLUSION: CS may provide a survival benefit for highly selected patients with PDAC and LM, including those with occult lesions, who respond well to multidisciplinary treatment.

Background & Aims: Age-related variation in the gut microbiota complicates biomarker discovery for pancreatic cancer. This study aimed to identify microbial taxa with minimal age dependence that are associated with pancreatic neoplasia and to develop a practical quantitative PCR (qPCR)-based assay targeting a shared gene involved in butyrate production. Study design: Cross-sectional study. Place and Duration of Study: Department of Gastroenterology and Hepatology, Fujita Health University, Toyoake, Japan, between October 2022 and July 2025. Methodology: Fecal samples from 64 individuals with precursor lesions considered to be at high risk for pancreatic cancer (HR) and 22 patients with pancreatic cancer (PC) were compared with those from healthy controls aged <50 years (Young; n = 71) and ≥50 years (Old; n = 65). Microbiota composition was analyzed by 16S rRNA gene sequencing. A qPCR primer set targeting the but gene, which encodes butyryl-CoA:acetate CoA-transferase, was designed to evaluate the shared genetic potential of the identified minimally age-dependent taxa, namely the Anaerostipes hadrus group and Agathobacter rectalis. Results: The A. hadrus group and A. rectalis showed disease-associated depletion with minimal age dependency. The qPCR assay showed no difference in but gene levels between the Young and Old groups (P = 0.3301). but gene levels in the HR group were comparable to those in the Old group (P > 0.9999), whereas levels in the PC group were significantly lower than those in the Old group (P = 0.0020) and the HR group (P = 0.0136). Conclusion: Targeting the but gene provides a practical approach to assessing the shared butyrate-producing potential of this minimally age-dependent microbial cluster. Within this cross-sectional cohort, but gene levels were preserved in HR individuals, whereas levels in the PC group were reduced, suggesting its potential utility as a non-invasive adjunct for future evaluation in longitudinal monitoring or risk assessment after prospective validation.

Aims: To evaluate the diagnostic potential of previously reported (5ar, nan) and novel microbial gene markers in fecal and salivary microbiomes for the non-invasive detection of colorectal cancer (CRC) progression. Study Design: Cross-sectional study. Place and Duration of Study: Department of Gastroenterology and Hepatology, Fujita Health University, Toyoake, Japan, between June 2024 and July 2025. Methodology: Fecal samples were collected from healthy controls (n = 65) and patients with colorectal adenoma (n = 38) or carcinoma (n = 27). Salivary samples were collected from healthy controls (n = 34) and the same patient cohorts. Microbial gene abundances were quantified via quantitative PCR, and microbiome composition was assessed using 16S rRNA gene sequencing. Group comparisons used the Kruskal-Wallis and Dunn’s tests. Beta diversity differences were evaluated by PERMANOVA. Results: In fecal samples, the abundances of 5ar, nan, and the Fusicatenibacter saccharivorans 16S rRNA gene (fsr) showed a stepwise decline from the adenoma stage onward, with significantly lower levels in carcinoma versus controls (5ar, P = 0.0023; nan, P = 0.0012; fsr, P = 0.0004). Conversely, in saliva, the Fusobacterium periodonticum tyrosine phenol lyase gene (tpl) was significantly reduced only in the carcinoma group (P = 0.0180). Fecal beta diversity differed significantly between controls and both colorectal neoplasia groups (both P ≤ 0.001), whereas salivary beta diversity differed only between controls and carcinoma patients (P = 0.014). Conclusion: Fecal and salivary microbial gene markers may serve as non-invasive, rapid, and cost-effective biomarkers for colorectal neoplasia. Fecal markers captured microbiota disruption at the adenoma stage (representing the early phase of CRC progression), whereas salivary markers predominantly reflected alterations specific to carcinoma (representing the later phase). Integrating these multi-niche biomarkers provides a promising clinical platform for early detection, monitoring of precursor lesions, and postoperative surveillance; however, validation in larger, independent cohorts is warranted.

Background and Aims: Crohn’s disease (CD) is a chronic inflammatory bowel disease characterized by gastrointestinal inflammation, with gut microbiota dysbiosis playing a key role in its onset and progression. This study aimed to evaluate whether 1-kestose supplementation modulates gut microbiota composition and mucin degradation–related biomarkers in patients with clinically inactive to mild CD, and to explore plausible ecological mechanisms in vitro. Study Design: Single-arm pilot intervention study with exploratory laboratory experiments. Place and Duration of Study: Samples were collected at Tokai University Hospital (Japan), and microbiome/qPCR analyses and in vitro assays were performed at Fujita Health University (Japan). The supplementation period was four months. Methodology: Nineteen patients with clinically inactive to mild CD (CDAI ≤ 220) received 1-kestose (3 g) twice daily for 4 months. Fecal microbiota composition was assessed by 16S rRNA gene sequencing, and qPCR quantified nanA homologs (nan levels) as a functional marker related to mucin-degrading potential. Clinical biomarkers (CDAI, fecal calprotectin, CRP, albumin) were monitored. To investigate potential mechanisms, in vitro cultures of Ruminococcus gnavus and Bifidobacterium longum were performed under sugar-supplemented conditions, including 1-kestose, and growth responses were evaluated; short-chain fatty acids (SCFAs) were descriptively assessed in pooled culture supernatants. Results: Clinical biomarkers remained stable throughout supplementation. 1-kestose intake was associated with an increased relative abundance of Bifidobacterium and a decreased abundance of Blautia, along with reduced fecal nan levels. In vitro, B. longum showed enhanced early growth with 1-kestose compared with other sugars, whereas R. gnavus exhibited impaired growth under acidic conditions. Exploratory SCFA measurements suggested higher acetate in sugar-supplemented B. longum cultures. Conclusion: In this single-arm pilot cohort of patients with clinically inactive to mild CD, 1-kestose supplementation was associated with shifts toward potentially beneficial taxa and a reduction in nan levels, a functional marker linked to mucin-degrading potential. These findings, supported by exploratory in vitro observations, suggest that 1-kestose may modulate gut ecological conditions; however, clinical efficacy and causality require confirmation in randomized, placebo-controlled trials with detailed dietary and medication monitoring.

BACKGROUND/AIM: Atezolizumab plus bevacizumab (Ate+Bev) is widely used as first-line therapy for unresectable hepatocellular carcinoma (HCC). However, a subset of patients experience early disease progression, often detected at the first radiologic assessment around 6 weeks. Evidence guiding second-line therapy in this subgroup is limited, and the clinical value of lenvatinib after early progressive disease (PD) remains unclear. PATIENTS AND METHODS: We retrospectively analyzed 36 patients with unresectable HCC who received lenvatinib after failure of first-line Ate+Bev. Patients were stratified by early PD, defined as radiologic progression at the scheduled 6-week assessment after starting Ate+Bev. Outcomes included antitumor response, progression-free survival (PFS), and overall survival (OS). RESULTS: Objective response rate (ORR) and disease control rate (DCR) assessed by RECIST 1.1 were comparable between patients with and without early PD (ORR: 28.6% vs. 13.8%; DCR: 85.7% vs. 86.2%; p=0.342). Median PFS was also similar between groups [5.2 months (95% confidence interval=1.9-NA) vs. 6.1 months (3.7-7.5); p=0.307]. In multivariate analyses adjusting for Child-Pugh class, Barcelona Clinic Liver Cancer (BCLC) stage, and reduced starting dose, early PD was not significantly associated with either PFS or OS, whereas Child-Pugh class A was independently associated with improved OS. Correlation between first- and second-line PFS was weak and non-significant (r=0.077, p=0.682). CONCLUSION: Lenvatinib demonstrated comparable antitumor activity and survival outcomes even in patients with early PD on first-line Ate+Bev, indicating that early radiologic progression does not necessarily signify refractoriness to subsequent systemic therapy. These findings support lenvatinib as a viable second-line option regardless of early Ate+Bev response, particularly in patients with preserved liver function. Larger prospective studies are needed to confirm these observations.

Aims: To characterize fecal gut microbiota features associated with a history of aggression in dogs and to explore whether supplementation with the prebiotic fructooligosaccharide 1-kestose is associated with alterations in gut microbiota composition and owner-reported aggression-related behaviors. Study Design: An exploratory, non-randomized field study comparing aggressive and non-aggressive client-owned dogs, followed by a single-arm pre–post supplementation study in aggressive dogs with owner-reported behavioral outcomes. Place and Duration of Study: The study was conducted in Japan between 2021 and 2023, with a 60-day 1-kestose supplementation period for the intervention group. Methodology: Fecal samples from aggressive toy poodles (Agg; n = 10) and non-aggressive controls (N-Agg; n = 6) were analyzed using 16S rRNA gene sequencing. Dogs in the Agg group received 1-kestose (400 mg/day) for 60 days. Behavioral outcomes were assessed before and after supplementation using the shortened, owner-reported Canine Behavioral Assessment and Research Questionnaire (C-BARQ). Genome analysis of Blautia caecimuris was conducted to identify glycoside hydrolase family 32 (GH32) enzymes, and a recombinant GH32 enzyme was functionally characterized for fructooligosaccharide hydrolysis. Results: At baseline, Agg dogs differed in gut microbial β-diversity from N-Agg dogs and showed higher relative abundances of Mediterraneibacter gnavus, the Segatella copri group, and the Phocaeicola vulgatus group. Following 1-kestose supplementation, M. gnavus was lower, the B. caecimuris group was higher, and the β-diversity difference between groups diminished. In parallel, owner-reported aggression-related C-BARQ items—particularly responses to unfamiliar dogs and strangers near the home—were lower after supplementation. The characterized GH32 enzyme from B. caecimuris hydrolyzed 1-kestose and nystose. Conclusion: These findings indicate that 1-kestose supplementation is associated with concurrent alterations in the canine gut microbiota and owner-reported aggression-related behavioral scores. While causality cannot be established, the results support further investigation of microbiota–behavior associations using larger, well-controlled study designs incorporating objective physiological and microbial measurements.

Background Foveolar‐type gastric adenomas with a raspberry‐like appearance in the stomach have recently been identified. However, their etiology and mechanisms of development and growth remain unknown. Case Presentation We observed a foveolar‐type gastric adenoma with a raspberry‐like appearance that underwent rapid morphological changes. The first esophagogastroduodenoscopy revealed multiple reddish polyps on the cardia and fundus of the stomach, without Helicobacter pylori infection. The second‐largest polyp on the fundus had a red glove appearance and measured 5 mm in diameter. We diagnosed all of them as hyperplastic polyps on the basis of their shape. Given that the patient had received 10 mg of vonoprazan for a long time to treat reflux esophagitis, 20 mg of famotidine was prescribed instead. Eight months later, the largest polyp on the cardia had disappeared. However, a reddish raspberry‐like lesion was observed at the site of a previously identified polyp on the fundus and was diagnosed as foveolar‐type gastric adenoma by forceps biopsy. The pathological diagnosis was foveolar‐type gastric adenoma with high‐grade dysplasia as determined by tissue resection with endoscopic mucosal resection (EMR). Conclusion This is a valuable case report of a lesion evolving from a hyperplastic‐like polyp morphology to a raspberry‐like lesion within eight months.

BACKGROUND: Atezolizumab plus bevacizumab (AB) is a standard first-line therapy for unresectable hepatocellular carcinoma (HCC). However, data on the efficacy and safety of AB rechallenge (re-AB) after discontinuation are limited. METHODS: We conducted a retrospective analysis of 13 patients with unresectable HCC who received initial AB treatment and re-AB at the University of Yamanashi and Fujita Health University. Rechallenge was defined as reinitiating AB after prior discontinuation followed by one or more other systemic therapies. Tumor responses were assessed using RECIST v1.1 and modified RECIST (mRECIST), and adverse events (AEs) were evaluated according to CTCAE v5.0. RESULTS: During initial AB, the objective response rate (ORR), disease control rate (DCR), and median progression-free survival (mPFS) were 15%, 69%, and 3.7 months, respectively. AB was discontinued due to disease progression or immune-related AEs. Re-AB was administered after a median of two intervening regimens. In the re-AB phase, ORR, DCR, and mPFS were 15%, 54%, and 4.7 months, respectively. Despite prior progression, two patients achieved partial response and five had stable disease. No worsening of previously observed AEs occurred during re-AB. CONCLUSIONS: AB rechallenge may be a safe and potentially effective treatment option for selected patients with unresectable HCC, even after discontinuation due to disease progression or adverse events.

AIM: This study evaluated the relationship between longitudinal dosing patterns and clinical outcomes of cabozantinib used as third- or later-line therapy in advanced hepatocellular carcinoma (HCC) previously treated with immune checkpoint inhibitors (ICIs), focusing on disease control (DC). METHODS: We retrospectively analyzed 33 patients with unresectable HCC who had received atezolizumab plus bevacizumab and lenvatinib, followed by cabozantinib. Tumor response was assessed by Response Evaluation Criteria in Solid Tumors v1.1, and patients were classified into DC (complete response/partial response/stable disease) or non-DC (progressive disease/not evaluable) groups. Initial dose, longitudinal dosing, and treatment outcomes were compared. RESULTS: Most patients (90.9%) started at reduced doses (40 mg/day: n = 18; 20 mg/day: n = 12), with only three starting at 60 mg/day. Objective response rate was 3.0%, and DC rate was 51.5%. Compared with the non-DC group, the DC group had significantly longer median progression-free survival (4.4 vs. 1.2 months; p < 0.0001), overall survival (10.7 vs. 3.0 months; p = 0.0456), and treatment duration (134 vs. 22 days; p < 0.0001). Time to first dose reduction and average daily dose over the first 6 weeks did not differ significantly between groups. Child-Pugh class A was independently associated with DC and survival. CONCLUSIONS: In real-world practice, cabozantinib is often initiated at reduced doses, yet DC can be achieved even at ∼20 mg/day. For patients with preserved liver function, long-term stable disease is attainable, and individualized dose-reduction strategies represent an effective and feasible approach in later-line HCC treatment after ICIs.

ABSTRACT Psychiatric disorders such as major depressive disorder are closely linked to the intestinal environment, suggesting intestinal health may contribute to their prevention. Prebiotics, which enhance intestinal health, are promising candidates for preventing psychiatric disorders. 1‐Kestose (kestose), a type of prebiotics, has shown potential, but its effects on psychiatric disorders remain unclear. In this study, we investigated whether kestose prevents abnormal behaviors induced by social isolation (SI) stress and which underlies mechanisms of preventive effects. C57BL/6J male mice (3 weeks old) were divided into two groups: individually housed (SI) group and housed five mice per cage (GH) group. Each group received either a normal diet or a kestose diet (5% kestose) for 5 weeks daily until the end of the behavioral testing. Kestose prevented the SI‐induced abnormal behaviors including reduced sociality, impaired spatial recognition, and heightened anxiety, which were associated with suppressed microglial activation in the hippocampus. Kestose altered the diversity of gut microbiota and increased the abundance of Bacteroides sartorii . Furthermore, short‐chain fatty acids (SCFAs) such as butyric acid, acetic acid, and propionic acid, produced by intestinal microbiota, were increased after kestose supplementation. Positive correlations were observed between B. sartorii abundance and SCFA levels, suggesting that B. sartorii contributes to SCFA production. Notably, both B. sartorii and SCFAs were strongly associated with the abnormal behaviors by SI. These findings suggest that kestose prevents SI‐induced abnormal behaviors by modulating gut microbiota, particularly B. sartorii , through an increase of SCFA production. Taken together, kestose could be used as a promising prebiotic intervention for psychiatric disorders. image

Shear wave elastography provides quantitative data on tissue stiffness, but was not available for endoscopic ultrasound until recently. The present study investigated the utility of a newly developed endoscopic ultrasound-guided shear wave measurement for diagnosing upper gastrointestinal subepithelial lesions. Shear wave velocity (Vs) was measured as an indicator of tissue stiffness, and the total amount of effective shear waves (VsN) was used as a reliability index for Vs values obtained by endoscopic ultrasound-guided shear wave measurements. Among the Vs values obtained, the five with the highest VsN were selected, and their median was defined as the median Vs (Vs-med). The median VsN of the five Vs values was defined as the median VsN (VsN-med). Endoscopic ultrasound-guided shear wave measurements were performed on 23 patients, with no complications occurring in any procedure. Histopathological diagnoses included 12 gastrointestinal stromal tumors, seven leiomyomas, and four schwannomas. Vs-med values for gastrointestinal stromal tumors, leiomyomas, and schwannomas were 2.46, 1.73, and 2.85 m/s, respectively, indicating that gastrointestinal stromal tumors and schwannomas were significantly stiffer than leiomyomas. VsN-med values for gastrointestinal stromal tumors, leiomyomas, and schwannomas were 40.5, 39, and 35.5%, respectively, with no significant differences. Endoscopic ultrasound-guided shear wave measurements are feasible for upper gastrointestinal subepithelial lesions and allow for the objective, non-invasive quantification of lesion stiffness. These results suggest the potential of endoscopic ultrasound-guided shear wave measurements as a valuable tool for the differential diagnosis of upper gastrointestinal subepithelial lesions.

BACKGROUND: Cancer gene panel testing (CGP) helps comprehensively analyze a large number of genes, extracting genetic information from the genome profile to aid treatment plans and drug therapy. Advances in drug therapy and surgical treatment for intrahepatic cholangiocarcinoma (ICC) have improved patient outcomes; however, it remains a typical intractable cancer with a poor prognosis. ICC is one of the key tumors for which effective treatment may be identified through CGP testing. This study aimed to identify ICC harboring actionable genetic variants using contrast-enhanced ultrasonography (CE-US). METHODS: We enrolled 26 ICC patients who underwent CE-US before chemotherapy or surgery. Three ultrasound specialists reviewed the images by consensus and assessed the imaging features, including vascularity. Pathological data were reviewed after diagnosis using CE-US. We retrospectively analyzed distinctive CE-US findings in patients with ICC with actionable genetic variants. RESULTS: Twelve ICC patients had actionable gene variants, including four FGFR2 fusions, one FGFR2 rearrangement, six IDH1 mutations, and one BRAF V600E mutation. Univariate analysis showed significant differences in bile duct invasion (p = 0.0217) and blood vessel penetration within the tumor (p = 0.0012). Multivariable logistic regression identified blood vessel penetration within the tumor (OR = 18.275; 95% CI: 1.331-250.925; p = 0.0297) as independently associated with actionable gene variants. CONCLUSION: Patients with ICC and blood vessel penetration on CE-US should be considered for CGP testing.

INTRODUCTION: Gastrectomy considerably affects the gut microbiome; however, the association between dysbiosis and post-gastrectomy syndrome remains to be explored. This study prospectively explored fecal gut microbiota alterations before and 3 months after gastrectomy, investigating their potential association with weight loss. METHODS: The gut microbiome of 21 patients with gastric cancer scheduled for gastrectomy in April-October 2022 was analyzed using 16S rRNA gene Next-Generation Sequencing. Their microbiome profiles were compared to those of healthy controls. Bacterial taxa demonstrating significant changes were determined using the Linear Discriminant Analysis Effect Size algorithm and further analyzed for their relationship with weight loss in the gastrectomy cohort. RESULTS: Postoperative complications (≥grade 2) were observed in 14.3% of patients. Postoperative weight loss was －10.9%, with the following breakdown: distal (－7.0%), total (－13.5%), and proximal (－14.0%) gastrectomy (P = 0.003). Microbiota analysis demonstrated a significant incline in the abundance of the Streptococcus salivarius group and a decline in Bacteroides uniformis in patients with gastric cancer compared to healthy controls. The S. salivarius group exhibited a further increase, while B. uniformis showed signs of recovery after gastrectomy. Additionally, 5α-reductase gene levels, reported to decrease as several cancers progress, were found to elevate post-surgery. Furthermore, patients experiencing greater weight loss showed a significant reduction in Faecalibacterium prausnitzii levels, while lower serum prealbumin and zinc levels were associated with the abundance of Escherichia coli. CONCLUSION: Gastrectomy significantly alters the gut microbiome. Supporting microbiome health with prebiotics may help alleviate postoperative issues and improve patients' quality of life.

Objective In 2021, anamorelin, an orally active ghrelin receptor selective antagonist, was approved for the treatment of cachexia in patients with non-small cell lung cancer, gastric cancer, pancreatic cancer, and colon cancer. Cancer cachexia is classified into three stages: pre-cachexia, cachexia, and refractory cachexia, with the pre-cachexia and cachexia stages considered reversible with a combination of nutritional therapy, pharmacotherapy, and exercise therapy. In addition, treatment of cachexia requires early intervention, but diagnosis and early detection of cachexia are difficult. We hypothesized that the initiation of anamorelin treatment may be delayed in clinical practice and explored the appropriate timing of treatment initiation. Methods The data of patients with cachexia who received anamorelin at our hospital from June 2021 to July 2023 were retrospectively reviewed. Anamorelin was administered to 201 patients, of whom 134 were included in the study. Survival time and duration of medication were compared based on the number of objective criteria for anamorelin prescription (C-reactive protein [CRP] >0.5 mg/dL, hemoglobin <12 g/dL, albumin <3.2 g/dL). Multivariate analysis was used to determine the factors associated with continuation of anamorelin treatment for 12 weeks. Results Patients with a higher number of objective criteria for anamorelin prescription (CRP >0.5 mg/dL, hemoglobin <12 g/dL, albumin <3.2 g/dL) had shorter anamorelin treatment duration and survival. In multivariate analysis, 12 weeks of anamorelin treatment was associated with CRP. Comparing CRP ≤0.5 mg/dL vs. CRP >0.5 mg/dL, survival was significantly longer for CRP ≤0.5 mg/dL (p < 0.01). Conclusions Initiating anamorelin treatment with close attention to CRP and ensuring that prescribing criteria are met may be helpful in treating cachexia.

The new Kyoto guidelines for the management of intraductal papillary mucinous neoplasm (IPMN) provide evidence-based recommendations for the diagnosis and treatment of IPMN. Endoscopic ultrasonography (EUS) is a diagnostic modality with a high spatial resolution that allows detailed observation and obtaining cyst fluid or tissue samples via EUS-guided fine needle aspiration (EUS-FNA). Currently, EUS is an indispensable examination method for the diagnosis of pancreatic diseases. On the other hand, there have been concerns that EUS imaging tends to be highly operator-dependent, and may lack objectivity. Previous guidelines have assigned EUS as an option for patients with worrisome features. However, recent reports indicate that the sensitivity of EUS for the diagnosis of mural nodules (MNs) is more than 90%, comparable or superior to that of contrast-enhanced computed tomography or magnetic resonance cholangiopancreatography. The specific advantages of EUS in the diagnosis of IPMN are: (1) high spatial resolution imaging for the diagnosis of MNs, (2) contrast-enhanced EUS for differentiation of intra-cystic MNs from mucous clots, and (3) pathological diagnosis using EUS-FNA and differential diagnosis of a pancreatic cystic tumor by cystic fluid analysis. In order to utilize EUS in the diagnosis of IPMN, endoscopists are required to have the skills to provide sufficiently objective imaging findings.

PURPOSE: This study aimed to clarify the current treatment status for biliary tract cancers based on data from the National Clinical Database (NCD) in Japan. METHODS: Total 3895 cases of biliary tract cancers registered in the NCD during 2021 were included. We identified the rates of resection, R0 resection, postoperative complications, and incidences of lymph node metastasis for gallbladder carcinoma, perihilar cholangiocarcinoma, distal bile duct carcinoma, and ampullary carcinoma. RESULTS: The number of biliary tract cancers registered in the NCD during 2021 was 3895 (1775 in extrahepatic bile duct carcinoma, 1422 in gallbladder carcinoma, and 698 in ampullary carcinoma). In gallbladder carcinoma, the resection (89.59%) and R0 resection rates (87.99%) were favorable, and the complication rate (6.05%) was lower than that of others. However, the postoperative complication rate could be higher in T3-T4 cases and when extrahepatic bile duct resection was performed concomitantly. Lymph node metastasis was frequently seen in 12.60% at the No. 13a lymph node. In perihilar cholangiocarcinoma, the R0 resection (69.82%) and complication rates (16.75%) were significantly lower and higher, respectively. In distal cholangiocarcinoma and ampullary carcinoma, metastasis was observed in approximately 2% and 10% of the dissected No. 16b1 para-aortic lymph nodes, respectively. In conclusion, although short-term surgical outcomes for biliary tract cancers in Japan might be acceptable, the significantly lower R0 resection and higher complication rates of perihilar cholangiocarcinomas indicate additional challenges for surgeons in the future and should continue to be monitored by the Japanese Society of Hepatobiliary and Pancreatic Surgery.

Feline atopic skin syndrome (FASS) is a chronic inflammatory skin disease characterized by itching and dermatitis. While the relationship between the gut microbiota and atopic dermatitis (AD) has been highlighted, exploring gut-targeted therapies for FASS remain limited. This study aimed to evaluate the effects of a parasynbiotic containing 1-kestose and heat-killed Lactobacillus plantarum FM8 on clinical symptoms and gut microbiota in cats with FASS. Eleven FASS cats were treated with a parasynbiotic containing 1-kestose (400 mg/day) and heat-killed FM8 (2.0 × 1010 CFU/day) for 8 weeks. Clinical symptoms were assessed using the SCORing Feline Allergic Dermatitis (SCORFAD), investigator pruritus score (IPS), and rating of global assessment of improvement (GAI). Fecal microbiota composition was analyzed through 16S rRNA sequencing, with 16 healthy cats serving as controls. Parasynbiotic intervention significantly reduced SCORFAD and IPS scores. GAI scores improved in 10 of 11 cats, with the most severe case maintaining a score of 3. The β-diversity analysis showed no significant differences; however, a trend toward variation was observed between the healthy control cats and the baseline group of FASS cats, as well as between the healthy control cats and post- intervention groups. The abundance of Collinsella stercoris was significantly higher in FASS cats than in healthy controls, and it significantly decreased after parasynbiotic intervention, suggesting potential improvements in gut health and inflammation. This study is the first to demonstrate the potential benefits of parasynbiotic administration in FASS, showing improvements in clinical symptoms and partial modulation of the gut microbiota. These findings highlight parasynbiotic administration as a compelling therapeutic approach for FASS, offering new possibilities for innovative interventions aimed at the gut–skin axis.

Recent studies have linked Ruminococcus gnavus to inflammatory bowel disease and Fusobacterium nucleatum to various cancers. Agarooligosaccharides (AOS), derived from the acid hydrolysis of agar, have shown significant inhibitory effects on the growth of R. gnavus and F. nucleatum at concentrations of 0.1 and 0.2%, respectively. RNA sequencing and quantitative reverse-transcription PCR analyses revealed the downregulation of fatty acid biosynthesis genes (fab genes) in these bacteria when exposed to 0.1% AOS. Furthermore, AOS treatment altered the fatty acid composition of R. gnavus cell membranes, increasing medium-chain saturated fatty acids (C8, C10) and C18 fatty acids while reducing long-chain fatty acids (C14, C16). In contrast, no significant growth inhibition was observed in several strains of Bifidobacteria and Lactobacillales at AOS concentrations of 0.2 and 2%, respectively. Co-culture experiments with R. gnavus and Bifidobacterium longum in 0.2% AOS resulted in B. longum dominating the population, constituting over 96% post-incubation. In vivo studies using mice demonstrated a significant reduction in the Lachnospiraceae family, to which R. gnavus belongs, following AOS administration. Quantitative PCR also showed lower levels of the nan gene, potentially associated with immune disorders, in the AOS group. These findings suggest that AOS may introduce a novel concept in prebiotics by selectively inhibiting potentially pathogenic bacteria while preserving beneficial bacteria such as Bifidobacteria and Lactobacillales.

Aim: This study aimed to establish a non-invasive, rapid, and cost-effective method to assess the potential risk of immune and psychiatric disorders by quantifying nan gene levels in gut microbiota, specifically focusing on Ruminococcus gnavus and other Lachnospiraceae species associated with mucin degradation. Methodology: We first designed a primer set targeting the consensus sequence of the nanA gene, which is highly conserved within nan gene clusters. To validate this primer set, we performed Next-Generation Sequencing (NGS) on the PCR-amplified fragments. To explore the association between nan levels and immune or psychiatric disorders, we conducted qPCR to quantify nan levels in the intestines, analyzing intestinal DNA from both allergy-induced mice with or without fructan treatment, and dogs with or without aggressive behavior. Additionally, to assess whether nan levels reflect the clinical status of immune disorders, fecal samples were collected from 45 patients with ulcerative colitis (UC) and analyzed for nan levels. Results: NGS analysis of DNA fragments amplified from various intestinal samples using the nan primer set confirmed the presence of nanA sequences from R. gnavus and other members of the Lachnospiraceae family, including Blautia and Dorea species. The qPCR quantification of nan levels using this primer set revealed that allergy-induced mice treated with fructans, which are known to be associated with lower allergy scores compared to untreated mice, exhibited significantly reduced nan levels. Additionally, the nan levels of aggressive dogs were substantially higher than those of non-aggressive dogs. Notably, nan levels were also substantially elevated in patients with UC in comparison to the healthy control individuals. Conclusion: qPCR-based measurement of nan levels in gut microbiota shows potential for selectively detecting pathogenic nan-harboring strains and may reflect the clinical status of immune and psychiatric disorders. This approach could provide a non-invasive, rapid, and cost-effective method for assessing the risk of these disorders.

AIM: To investigate the characteristics and prognosis of patients with advanced hepatocellular carcinoma (HCC) treated with atezolizumab and bevacizumab (Atz/Bev) who achieved a complete response (CR) according to the modified Response Evaluation Criteria in Solid Tumors (mRECIST). METHODS: A total of 120 patients with Eastern Cooperative Oncology Group performance status (PS) 0 or 1 and Child-Pugh A at the start of Atz/Bev treatment were included. Barcelona Clinic Liver Cancer stage C was recorded in 59 patients. RESULTS: The CR rate with Atz/Bev alone was 15.0%. The median time to CR was 3.4 months, and the median duration of CR was 15.6 months. A significant factor associated with achieving CR with Atz/Bev alone was an AFP ratio of 0.34 or less at 3 weeks. Adding transarterial chemoembolization (TACE) in the six patients who achieved a partial response increased the overall CR rate to 20%. Among the 24 patients who achieved CR, the median progression-free survival was 19.3 months, the median overall survival was not reached, and 14 patients (58.3%) were able to discontinue Atz/Bev and achieve a drug-free status. Twelve of these patients developed progressive disease (PD), but eleven successfully received post-PD treatments and responded well. CONCLUSIONS: Achieving CR by mRECIST using Atz/Bev alone or with additional TACE can be expected to offer an extremely favorable prognosis.