廣岡 芳樹

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.

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.

Introduction. Hepatocellular carcinoma (HCC) is one of the deadliest cancers worldwide.Gap statement. Monitoring of HCC and predicting its immunotherapy responses are challenging.Aim. This study explored the potential of the gut microbiome for HCC monitoring and predicting HCC immunotherapy responses.Methods. DNA samples were collected from the faeces of 22 patients with HCC treated with atezolizumab/bevacizumab (Atz/Bev) and 85 healthy controls. The gut microbiome was analysed using 16S rRNA next-generation sequencing and quantitative PCR (qPCR).Results. The microbiomes of patients with HCC demonstrated significant enrichment of Lactobacillus, particularly Lactobacillus fermentum, and Streptococcus, notably Streptococcus anginosus. Comparative analysis between Atz/Bev responders (R) and non-responders (NR) revealed a higher abundance of Bacteroides stercoris in the NR group and Bacteroides coprocola in the R group. Using qPCR analysis, we observed elevated levels of S. anginosus and reduced levels of 5α-reductase genes, essential for the synthesis of isoallolithocholic acid, in HCC patients compared to controls. Additionally, the analysis confirmed a significantly lower abundance of B. stercoris in the Atz/Bev R group relative to the NR group.Conclusions. The gut microbiome analysis and specific gene quantification via qPCR could provide a rapid, less invasive, and cost-effective approach for assessing the increased risk of HCC, monitoring patient status, and predicting immunotherapy responses.

Less than half of all patients diagnosed with pancreatic ductal adenocarcinoma (PDAC) respond to chemotherapy, and the prognosis of PDAC is poor, which may be mediated by the gut microbiota. We investigated the clinical improvement effects of 1-kestose, a fructooligosaccharide, on PDAC chemotherapy in this single-center, randomized, controlled pilot trial conducted at Fujita Health University Hospital, which enrolled patients with PDAC. The trial included 1-kestose administration and non-administration groups. The 1-kestose group received 9 g of 1-kestose daily for 12 weeks, and their blood markers, imaging studies, physical findings, and gut microbiota were evaluated. In the 1-kestose administration group, the cancer marker CA19-9 significantly decreased, and there was a reduction in the neutrophil-to-lymphocyte ratio (NLR). There was also suppression of the reduction of albumin levels and of an increase in C-reactive protein. Additionally, Escherichia coli, which typically increases in PDAC, significantly decreased in the 1-kestose group. Thus, 1-kestose altered the gut microbiota and improved the prognostic factors for PDAC. Large-scale, long-term trials of 1-kestose interventions for PDAC are thus warranted to improve the prognosis of PDAC.