Concurrent targeting of GSK3 and MEK as a therapeutic strategy to treat pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies worldwide. However, drug discovery for PDAC treatment has proven complicated, leading to stagnant therapeutic outcomes. Here, we identify Glycogen synthase kinase 3 (GSK3) as a therapeutic target through a whole-body genetic screening utilizing a '4-hit' Drosophila model mimicking the PDAC genotype. Reducing the gene dosage of GSK3 in a whole-body manner or knocking down GSK3 specifically in transformed cells suppressed 4-hit fly lethality, similar to Mitogen-activated protein kinase kinase (MEK), the therapeutic target in PDAC we have recently reported. Consistently, a combination of the GSK3 inhibitor CHIR99021 and the MEK inhibitor trametinib suppressed the phosphorylation of Polo-like kinase 1 (PLK1) as well as the growth of orthotopic human PDAC xenografts in mice. Additionally, reducing PLK1 genetically in 4-hit flies rescued their lethality. Our results reveal a therapeutic vulnerability in PDAC that offers a treatment opportunity for patients by inhibiting multiple targets.

Impact of Neutrophil Extracellular Traps Identified by Citrullinated Histone H3 Immunohistochemistry for Postoperative Prognosis in Patients with Extrahepatic Cholangiocarcinomas.

BACKGROUND: Neutrophil extracellular traps (NETs) are extracellular chromatin structures composed of cytoplasmic, granular, and nuclear components of neutrophils. Recently, NETs have received much attention for their role in tumor biology; however, their impact on the postoperative prognosis of patients with extrahepatic cholangiocarcinomas (EHCCs) remains unclear. The purpose of this study was to clarify the impact of NETs identified by immunohistochemical citrullinated histone H3 (Cit-H3) staining on postoperative overall survival (OS) in patients with perihilar cholangiocarcinoma (PHCC) and distal cholangiocarcinoma (DCC). METHODS: This study included 318 patients with EHCC (PHCC, n = 192; DCC, n = 126) who underwent surgical resection with curative intent. Neutrophils and NETs were identified by immunohistochemistry using antibodies against CD15 and Cit-H3, respectively. Based on the distribution of CD15 and Cit-H3 expression in the tumor bed, the patients were classified into four groups: one negative group and three subgroups of the positive group (diffuse, intermediate, and focal subgroups). RESULTS: No significant difference was found in the postoperative OS rate depending on the distribution of CD15 expression in patients with PHCC or DCC. However, the three subgroups with positive Cit-H3 expression had significantly poorer OS than the negative group for both PHCC and DCC. Moreover, positive Cit-H3 was an independent OS factor in the multivariable analyses of PHCC (hazard ratio [HR] 1.69, 95% confidence interval [CI] 1.11-2.59, P = 0.0115) and DCC (HR 2.03; 95% CI 1.21-3.42, P = 0.0057). CONCLUSIONS: The presence of NETs in the tumor microenvironment may have adverse prognostic effects in patients with EHCCs.

Postoperative Prognosis According to Pathologic Categorization of Desmoplastic Reaction in Patients with Extrahepatic Cholangiocarcinoma.

BACKGROUND: Recent studies have demonstrated the importance of desmoplastic reaction (DR) in predicting postoperative prognosis for patients with colorectal carcinoma. However, the impact of DR on the prognosis of extrahepatic cholangiocarcinomas (EHCCs) is not established. This study aimed to clarify the associations of pathologic DR categories with clinicopathologic factors and postoperative prognosis of perihilar cholangiocarcinoma (PHCC) and distal cholangiocarcinoma (DCC). METHODS: A pathologic review of 174 patients with PHCC and 109 patients with DCC who underwent surgical resection was performed. The patients were classified into three DR categories (immature, intermediate, and mature) based on the histologic features within the fibrotic stroma in the invasive front. The association between DR categories and the distribution of fibroblasts with anti-α-smooth muscle actin (SMA) expression, seeming to be tumor-promoting cancer-associated fibroblasts (CAFs), was evaluated in 191 tissue microarray specimens of EHCCs. RESULTS: Intermediate/immature DR categories were significantly associated with a more invasive nature, including higher pT and pN stages and more tumor buds than the mature category in both PHCC and DCC. The DR categories could stratify overall survival (OS) and relapse-free survival (RFS) in both PHCC and DCC patients. In the multivariate analysis, the DR category was an independent prognostic factor for OS and RFS in both PHCC and DCC (p < 0.001). The mature and immature DR categories were significantly associated respectively with the confined and pervasive distribution of fibroblasts with α-SMA expression. CONCLUSION: In patients with EHCCs, DR categorization was an independent prognostic factor reflecting the distribution of tumor-promoting CAFs in the invasive front.

Clinical significance of dispersion imaging by shear wave elastography in the treatment and diagnosis of pancreatic cancer.

BACKGROUND AND AIM: Recently, dispersion imaging by shear wave elastography has been developed to visualize a tissue viscosity-related factor by measuring the dispersion slope. However, clinical significance of dispersion imaging in the field of pancreatic cancer is unknown. This study aimed to investigate the clinical significance of dispersion imaging in the treatment and diagnosis of pancreatic cancer. METHODS: We measured shear wave dispersion slope (SWD) (m/s/kHz) and shear wave elasticity (SWE) (kPa) in patients with pancreatic ductal adenocarcinoma (PDA). The primary endpoint was the relationship between the changes in SWD and SWE values before and after chemotherapy and the response to chemotherapy. Secondary endpoints included SWD and SWE values in relation to differences between PDA and non-PDA sites and histopathological scores of stroma, inflammation, fibrosis, and necrosis in endoscopic ultrasound-guided fine-needle aspiration specimens. RESULTS: Fifty-six patients were included, 30 of whom underwent chemotherapy. There was no relationship between the changes of SWD and SWE values and chemotherapy responses. In 56 patients, the median SWD value was 12.20 m/s/kHz (interquartile range [IQR]: 10.88-13.61) at PDA sites and 13.57 m/s/kHz (IQR: 12.28-16.20) at non-PDA sites (P = 0.005). The median SWE value was 8.18 kPa (IQR: 7.00-9.74) at PDA sites and 6.14 kPa (IQR: 5.40-6.77) at non-PDA sites (P < 0.001). Histopathological evaluation revealed that inflammation scores were correlated with SWD values (rs  = 0.42, P < 0.001). CONCLUSIONS: Dispersion imaging in pancreatic cancer would be useful for diagnosis and assessing inflammation.

[A Case of Testicular Cancer with Solitary Iliac Bone Metastasis].

A 23-year-old male was aware of pain around his left hip joint and visited a nearby orthopedic clinic. Swelling of the right testis was pointed out, and a testicular tumor was suspected. He was referred to the urology department of a local hospital. Blood analysis showed an increase of α-fetoprotein (AFP) (3,620 ng/ml). Computed tomographic (CT) -scan revealed a left iliac bone metastasis and morbid fracture. Right radical inguinal orchiectomy was performed. The pathological examination revealed mixed germ cell tumor (embryonic carcinoma and immature teratoma: 70%, seminoma: 30%). The diagnosis was non-seminomatous germ cell tumor, stage IIIc, and poor risk on the International Germ Cell Consensus Classification. After one cycle of a bleomycin, etoposide and cisplatinum (BEP) regimen, he was referred to our hospital. After a total of 4 cycles of BEP, AFP was normalized. Denosumab was also administered monthly. The CT-scan showed a reduction of bone metastasis and recovery of ossification. Bone biopsy did not show viable tumor cells. Because extirpation of the remaining mass would require resection of the left part of the pelvic bone with significant functional loss of the left limb, we performed close follow-up after an additional 2 courses of the etoposide and cisplatin regimen. The patient is currently alive without recurrence at 45 months after the last systemic chemotherapy.

Predictors of Long-Term Survival in Pancreatic Ductal Adenocarcinoma after Pancreatectomy: TP53 and SMAD4 Mutation Scoring in Combination with CA19-9.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDA) is a fatal cancer for which even unfavorable clinicopathological factors occasionally fail to preclude long-term survival. We sought to establish a scoring system that utilizes measurable pre-intervention factors for predicting survival following surgical resection. METHODS: We retrospectively analyzed 34 patients who died from short-term recurrences and 32 long-term survivors among 310 consecutively resected patients with PDA. A logistic regression model was used to define factors related to clinical parameters, molecular profiles of 18 pancreatic cancer-associated genes, and aberrant expression of major tumor suppressors. RESULTS: Carbohydrate antigen 19-9 (CA19-9) had the best ability to classify patients with short-term recurrence and long-term survivors [odds ratio 21.04, 95% confidence interval (CI) 4.612-96.019], followed by SMAD4 and TP53 mutation scoring (odds ratio 41.322, 95% CI 3.156-541.035). Missense TP53 mutations were strongly associated with the nuclear expression of p53, whereas truncating mutations were associated with the absence of nuclear p53. The former subset was associated with a worse prognosis. The combination of aberrant SMAD4 and mutation types of TP53 exhibited a better resolution for distinguishing patients with short-term recurrences from long-term survivors (compared with the assessment of the number of mutated KRAS, CDKN2A, TP53, and SMAD4 genes). Calibration of mutation scores combined with CA19-9 in a logistic regression model setting demonstrated a practical effect in classifying long survivors and patients with early recurrence (c-statistic = 0.876). CONCLUSIONS: Genetic information, i.e., TP53 mutation types and SMAD4 abnormalities, combined with CA19-9, will be a valuable tool for improving surgical strategies for pancreatic cancer.

Tumor-Informed Approach Improved ctDNA Detection Rate in Resected Pancreatic Cancer.

Pancreatic cancer is one of the cancers with very poor prognosis; there is an urgent need to identify novel biomarkers to improve its clinical outcomes. Circulating tumor DNA (ctDNA) from liquid biopsy has arisen as a promising biomarker for cancer detection and surveillance. However, it is known that the ctDNA detection rate in resected pancreatic cancer is low compared with other types of cancer. In this study, we collected paired tumor and plasma samples from 145 pancreatic cancer patients. Plasma samples were collected from 71 patients of treatment-naïve status and from 74 patients after neoadjuvant therapy (NAT). Genomic profiling of tumor DNA and plasma samples was conducted using targeted next-generation sequencing (NGS). Somatic mutations were detected in 85% (123/145) of tumors. ctDNA was detected in 39% (28/71) and 31% (23/74) of treatment-naïve and after-NAT groups, respectively, without referring to the information of tumor profiles. With a tumor-informed approach (TIA), ctDNA detection rate improved to 56% (40/71) and 36% (27/74) in treatment-naïve and after-NAT groups, respectively, with the detection rate significantly improved (p = 0.0165) among the treatment-naïve group compared to the after-NAT group. Cases who had detectable plasma ctDNA concordant to the corresponding tumor showed significantly shorter recurrence-free survival (RFS) (p = 0.0010). We demonstrated that TIA improves ctDNA detection rate in pancreatic cancer, and that ctDNA could be a potential prognostic biomarker for recurrence risk prediction.

Targeted amplicon sequencing for primary tumors and matched lymph node metastases in patients with extrahepatic cholangiocarcinoma.

BACKGROUND: Lymph node metastasis (LNM) is one of the most adverse prognostic factors in extrahepatic cholangiocarcinoma (EHCC) cases. As next-generation sequencing technology has become more widely available, the genomic profile of biliary tract carcinoma has been clarified. However, whether LNMs have additional genomic alterations in patients with EHCC has not been investigated. Here, we aimed to compare the genomic alterations between primary tumors and matched LNMs in patients with EHCC. METHODS: Sixteen patients with node-positive EHCCs were included. Genomic DNA was extracted from tissue samples of primary tumors and matched LNMs. Targeted amplicon sequencing of 160 cancer-related genes was performed. RESULTS: Among the 32 tumor samples from 16 patients, 91 genomic mutations were identified. Genomic mutations were noted in 31 genes, including TP53, MAP3K1, SMAD4, APC, and ARID1A. TP53 mutations were most frequently observed (12/32; 37.5%). Genomic mutation profiles were highly concordant between primary tumors and matched LNMs (13/16; 81.3%), and an additional genomic mutation of CDK12 was observed in only one patient. CONCLUSION: Genomic mutations were highly concordant between primary tumors and matched LNMs, suggesting that genotyping of archived primary tumor samples may help predict genomic mutations of metastatic tumors in patients with EHCC.

[Leukemia Relapse as Granulocytic Sarcoma Beginning with Penile Localization : A Case Report].

A 57-year-old man visited the urology department with a painful mass on the dorsal side of the penis. Magnetic resonance imaging sagittal image showed a small nodule. Leukemia recurrence was suspected due to his history of treatment for acute myeloid leukemia treated with allogeneic hematopoietic stem cell transplantation. No recurrence was identified by bone marrow biopsy ; however, two months later, the recurrence of leukemia was strongly suspected because the tumor grew over time and blasts were found in the peripheral blood. A biopsy of the penile tumor and bone marrow was performed, leading to the diagnosis of granulocytic sarcoma. Patients with a history of leukemia may be preceded by a single recurrence to extramedullary organs, even if blood and bone marrow findings suggest remission.

[Successful treatment of a fulminant-type Wilson's disease with deceased donor liver transplantation after recovery from critical illness].

A 15-year-old female patient was diagnosed with a fulminant-type Wilson's disease. She had severe illness with a Model for End-Stage Liver Disease score of 25 and new Wilson Index score of 11. She underwent plasma exchanges, hemodiafiltration, and administration of fresh frozen plasma on consecutive days. Finally, she had recovered from severe illness and was discharged from the hospital. After 18 months of waiting time, she underwent deceased liver transplantation and returned to normal daily life. In Japan, the critical shortage of donated organs requires a long waiting time. Previous studies demonstrated that artificial liver support systems, including plasma exchange and hemodiafiltration, could be useful for a fulminant-type Wilson's disease. For such a disease, multidisciplinary bridging treatments are crucial for a successful liver transplantation.

A case of Epstein-Barr virus-associated lymphoepithelioma-like carcinoma of the colon.

Lymphoepithelioma-like carcinoma is a poorly differentiated carcinoma with prominent lymphoid infiltration occurring in various organs but is exceedingly rare in the colorectal region. This malignancy is frequently associated with Epstein-Barr virus (EBV). Here we report a case of EBV-associated lymphoepithelioma-like carcinoma of the cecum in an 84-year-old male who presented with occult blood. In situ hybridization for EBV-encoded small RNAs (EBER) in an endoscopic submucosal dissection specimen showed that the tumor consisted of EBER-negative well-differentiated tubular adenocarcinoma and EBER-positive lymphoepithelioma-like carcinoma. Real-time PCR detected 7.16 copies of the EBV genome per cell in a sample microdissected from the latter component. Genotyping analysis demonstrated EBV genotype 1, and viral protein/transcript expression in the tumor showed EBV latency I. Expression of Ephrin receptor A2, a recently reported receptor for EBV, was demonstrated in the tumor cells by immunohistochemistry. To our knowledge, this is the first report of lymphoepithelioma-like carcinoma in the colorectal region showing a definite association with EBV infection.

Silent pituitary adenoma and metabolic disorders: obesity, abnormal glucose tolerance, hypertension and dyslipidemia.

A silent pituitary adenoma (SPA) is characterized by the expression of pituitary hormones, detected by immunohistochemical staining, in the absence of clinical signs or symptoms of hormonal excess. Compared with functional pituitary adenomas, little is known regarding the involvement of SPAs in metabolic disorders. This study aimed to examine the correlations between SPAs and metabolic disorders, including obesity, abnormal glucose tolerance, hypertension and dyslipidemia. Seventy-four patients with nonfunctional pituitary adenomas who underwent a pituitary adenomectomy in Hokkaido University Hospital from 2008 to 2016 were retrospectively examined. Pituitary adenomas were immunohistochemically classified into pituitary hormone positive or negative groups. Twenty whole hormone-negative pituitary adenomas were excluded because we couldn't identify pituitary transcription factors which is necessary for the diagnosis of a null cell adenoma. The preoperative rates of obesity, abnormal glucose tolerance, hypertension and dyslipidemia were compared between each group. Twenty-seven GH positive adenomas (50.0%), 32 gonadotroph positive adenomas (59.3%), 28 TSH positive adenomas (51.9%) and 21 ACTH positive adenomas (38.9%) were identified. Evaluation of the preoperative clinical data showed 25 cases of obesity (46.2%), 16 cases of abnormal glucose tolerance (29.6%), 29 cases of hypertension (53.7%) and 35 cases of dyslipidemia (64.8%). The rate of hypertension was significantly lower in the GH positive group (37.0%) than the GH negative group (70.4%) (p = 0.0140). In the GH negative group, postoperative systolic and diastolic blood pressure levels were significantly lower than preoperative values. GH positive SPAs may affect the homeostasis of blood pressure.

Distinct TERT promoter C228T and C250T mutations in a patient with an oligodendroglioma: A case report.

The majority of oligodendroglial tumors harbor mutations in the telomerase reverse transcriptase (TERT) gene (TERT) promoter and the isocitrate dehydrogenase 1/2 (IDH1/2) gene (IDH1/2), as well as 1p/19q codeletion. Generally, TERT promoter mutations, C250T and C228T, are mutually exclusive. We present a case of oligodendroglioma harboring both C250T and C228T mutations in TERT promoter. A 38-year-old man presented with grand mal seizures and underwent a resection surgery for a left frontal lobe tumor. He was pathologically diagnosed as having oligodendroglioma and was carefully observed. At 48 years of age, he underwent another resection surgery due to tumor regrowth, with the pathological diagnosis of anaplastic oligodendroglioma. Genetic analysis of the initial tumor specimen revealed IDH1 R132H mutation and both C250T and C228T mutations in TERT promoter. Using mutation-specific primers, two mutations were considered to be distributed in different alleles. In the tumor specimen obtained during the second surgery, IDH1 R132H mutation was detected to be similar to that of the initial specimen; however, only C228T mutation was detected in TERT promoter. The 1p/19q codeletion was detected in both the initial and recurrent tumor specimens. According to the sequencing data from the two tumor specimens, although TERT promoter mutation has been considered to be an early genetic event in the tumorigenesis of oligodendroglial tumors, it is likely that the C250T and C228T mutations in TERT promoter are subclonally distributed in the same tumor specimen of the present case.

Signaling adaptor protein Crk is involved in malignant feature of pancreatic cancer associated with phosphorylation of c-Met.

Signaling adaptor protein Crk has been shown to play an important role in various human cancers. Crk links tyrosine kinases and guanine nucleotide exchange factors (GEFs) such as C3G and Dock180 to activate small G-proteins Rap and Rac, respectively. In pancreatic cancer, various molecular targeted therapies have provided no significant therapeutic benefit for the patients so far due to constitutive activation of KRAS by frequent KRAS mutation. Therefore, the establishment of novel molecular targeted therapy in KRAS-independent manner is required. Here, we investigated a potential of Crk as a therapeutic target in pancreatic cancer. Immunohistochemistry on human pancreatic cancer specimens revealed that the patients with high expression of Crk had a worse prognosis than those with low expression. We established Crk-knockdown pancreatic cancer cells by siRNA using PANC-1, AsPC-1, and MIA PaCa-2 cells, which showed decreased cell proliferation, invasion, and adhesion. In Crk-knockdown pancreatic cancer cells, the decrease of c-Met phosphorylation was observed. In the orthotopic xenograft model, Crk depletion prolonged survival of mice significantly. Thus, signaling adaptor protein Crk is involved in malignant potential of pancreatic cancer associated with decrease of c-Met phosphorylation, and Crk can be considered to be a potential therapeutic molecular target.

Guidance for diagnosing autoimmune pancreatitis with biopsy tissues.

The biopsy-based diagnosis of autoimmune pancreatitis (AIP) is difficult but is becoming imperative for pathologists due to the increased amount of endoscopic ultrasound-guided biopsy tissue. To cope with this challenge, we propose guidance for the biopsy diagnosis of type 1 AIP. This guidance is for pathologists and comprises three main parts. The first part includes basic issues on tissue acquisition, staining, and final diagnosis, and is intended for gastroenterologists as well. The second part is a practical guide for diagnosing type 1 AIP based on the AIP clinical diagnostic criteria 2018. Inconsistent histological findings, tips for evaluating IgG4 immunostaining and key histological features including the ductal lesion and others are explained. Storiform fibrosis and obliterative phlebitis are diagnostic hallmarks but are sometimes equivocal. Storiform fibrosis is defined as spindle-shaped cells, inflammatory cells and fine collagen fibers forming a flowing arrangement. Obliterative phlebitis is defined as fibrous venous obliteration with inflammatory cells. Examples of each are provided. The third part describes the differentiation of AIP from pancreatic ductal adenocarcinoma (PDAC), focusing on histological features of acinar-ductal metaplasia in AIP, which is an important mimicker of PDAC. This guidance will help standardize pathology reports of pancreatic biopsies for diagnosing type 1 AIP.

An increase in the peripheral lymphocyte-to-monocyte ratio after primary site resection is associated with a prolonged survival in unresectable colorectal carcinoma.

PURPOSE: The prognostic benefits of primary tumor resection in patients with unresectable distant metastatic colorectal cancer remain unclear. A high pre-treatment lymphocyte-to-monocyte ratio (LMR) was previously shown to be associated with a better prognosis. We assessed whether or not primary tumor resection was associated with an improved survival if the peripheral lymphocyte-to-monocyte ratio increased after primary site resection. METHODS: The survival in 64 and 59 patients with and without primary tumor resection, respectively, was retrospectively compared. After resection, the survival in 39 patients with a postoperatively increased LMR (LMR-increase) and 25 patients with a decreased LMR (LMR-decrease) was compared. RESULTS: Primary tumor resection prolonged the median survival more frequently in cases of non-differentiated adenocarcinoma, obstructive symptoms, high serum albumin levels, and no lymph-node metastasis than in others. Cox regression showed that the potential independent prognostic variable was non-resection of the primary lesion. After resection, the median survival in the LMR-increase vs. LMR-decrease groups was significantly different (27.3 vs. 20.8 months). There were no marked differences in patient background characteristics between the groups, except for in the number of pre-operative peripheral blood lymphocytes. The resected specimens showed significantly lower CD8+:CD163+ invading leukocyte ratios in the LMR-increase group than in the LMR-decrease group. CONCLUSIONS: Primary tumor resection in patients with unresectable metastatic colorectal cancer may be associated with an improved survival, especially when the LMR is increased after primary tumor resection.

Impact of tumour budding grade in 310 patients who underwent surgical resection for extrahepatic cholangiocarcinoma.

AIMS: Tumour budding is a risk factor for poor prognosis in various cancers. Tumour buds may present an epithelial-mesenchymal transition (EMT) morphological phenotype. This study aimed to elucidate the prognostic impact of tumour budding grade and its association with clinicopathological and EMT-related features in perihilar cholangiocarcinoma (PHCC) or distal cholangiocarcinoma (DCC). METHODS AND RESULTS: Subjects included 195 PHCC and 115 DCC patients. The numbers of tumour buds in different patients were stratified for postoperative survival using the recursive partitioning technique. Consequently, the numbers of tumour buds in PHCC patients were classified into three grades; namely, low (0-4 buds); intermediate (5-11 buds); and high (≥12 buds); those of DCC patients were classified into two grades; namely, low (0-4 buds) and high (≥5 buds). In both PHCC and DCC patients, high tumour budding grade was associated with poor histological differentiation, higher pT factor, presence of lymphatic, venous, perineural invasion and regional lymph node metastasis. In PHCC patients, residual invasive tumour in the resected margin was also associated with high tumour budding grade. For both PHCC and DCC patients, high tumour budding grade was an independent adverse prognostic factor in multivariate analysis (P < 0001 and P = 0.046, respectively). Immunohistochemical examination revealed that the number of tumour buds increased in patients with tumours showing a mesenchymal profile (negative for E-cadherin and positive for vimentin). CONCLUSIONS: Higher tumour budding grade is associated with invasive clinicopathological features, adverse postoperative prognosis and EMT status in extrahepatic cholangiocarcinoma.

Genomic characterization of biliary tract cancers identifies driver genes and predisposing mutations.

BACKGROUND & AIMS: Biliary tract cancers (BTCs) are clinically and pathologically heterogeneous and respond poorly to treatment. Genomic profiling can offer a clearer understanding of their carcinogenesis, classification and treatment strategy. We performed large-scale genome sequencing analyses on BTCs to investigate their somatic and germline driver events and characterize their genomic landscape. METHODS: We analyzed 412 BTC samples from Japanese and Italian populations, 107 by whole-exome sequencing (WES), 39 by whole-genome sequencing (WGS), and a further 266 samples by targeted sequencing. The subtypes were 136 intrahepatic cholangiocarcinomas (ICCs), 101 distal cholangiocarcinomas (DCCs), 109 peri-hilar type cholangiocarcinomas (PHCs), and 66 gallbladder or cystic duct cancers (GBCs/CDCs). We identified somatic alterations and searched for driver genes in BTCs, finding pathogenic germline variants of cancer-predisposing genes. We predicted cell-of-origin for BTCs by combining somatic mutation patterns and epigenetic features. RESULTS: We identified 32 significantly and commonly mutated genes including TP53, KRAS, SMAD4, NF1, ARID1A, PBRM1, and ATR, some of which negatively affected patient prognosis. A novel deletion of MUC17 at 7q22.1 affected patient prognosis. Cell-of-origin predictions using WGS and epigenetic features suggest hepatocyte-origin of hepatitis-related ICCs. Deleterious germline mutations of cancer-predisposing genes such as BRCA1, BRCA2, RAD51D, MLH1, or MSH2 were detected in 11% (16/146) of BTC patients. CONCLUSIONS: BTCs have distinct genetic features including somatic events and germline predisposition. These findings could be useful to establish treatment and diagnostic strategies for BTCs based on genetic information. LAY SUMMARY: We here analyzed genomic features of 412 BTC samples from Japanese and Italian populations. A total of 32 significantly and commonly mutated genes were identified, some of which negatively affected patient prognosis, including a novel deletion of MUC17 at 7q22.1. Cell-of-origin predictions using WGS and epigenetic features suggest hepatocyte-origin of hepatitis-related ICCs. Deleterious germline mutations of cancer-predisposing genes were detected in 11% of patients with BTC. BTCs have distinct genetic features including somatic events and germline predisposition.