Type Intrahepatic Cholangiocarcinoma Research Articles

Small duct and large duct type intrahepatic cholangiocarcinoma reveal distinct patterns of immune signatures

PurposeDedicated gene signatures in small (SD-iCCA) and large (LD-iCCA) duct type intrahepatic cholangiocarcinoma remain unknown. We performed immune profiling in SD- and LD-iCCA to identify novel biomarker candidates for personalized medicine.MethodsRetrospectively, 19 iCCA patients with either SD-iCCA (n = 10, median age, 63.1 years (45–86); men, 4) or LD-iCCA (n = 9, median age, 69.7 years (62–85); men, 5)) were included. All patients were diagnosed and histologically confirmed between 04/2009 and 01/2021. Tumor tissue samples were processed for differential expression profiling using NanoString nCounter® PanCancer Immune Profiling Panel.ResultsWith the exception of complement signatures, immune-related pathways were broadly downregulated in SD-iCCA vs. LD-iCCA. A total of 20 immune-related genes were strongly downregulated in SD-iCCA with DMBT1 (log2fc = -5.39, p = 0.01) and CEACAM6 (log2fc = -6.38, p = 0.01) showing the strongest downregulation. Among 7 strongly (log2fc > 2, p ≤ 0.02) upregulated genes, CRP (log2fc = 5.06, p = 0.02) ranked first, and four others were associated with complement (C5, C4BPA, C8A, C8B). Total tumor-infiltrating lymphocytes (TIL) signature was decreased in SD-iCCA with elevated ratios of exhausted-CD8/TILs, NK/TILs, and cytotoxic cells/TILs while having decreased ratios of B-cells/TILs, mast cells/TILs and dendritic cells/TILs. The immune profiling signatures in SD-iCCA revealed downregulation in chemokine signaling pathways inclulding JAK2/3 and ERK1/2 as well as nearly all cytokine-cytokine receptor interaction pathways with the exception of the CXCL1/CXCR1-axis.ConclusionImmune patterns differed in SD-iCCA versus LD-iCCA. We identified potential biomarker candidate genes, including CRP, CEACAM6, DMBT1, and various complement factors that could be explored for augmented diagnostics and treatment decision-making.

Subtype prediction of intrahepatic cholangiocarcinoma using dynamic contrast-enhanced ultrasound

ObjectiveThe study aimed to investigate the predictive value of dynamic contrast-enhanced ultrasound (DCE-US) in differentiating small-duct (SD) and large-duct (LD) types of intrahepatic cholangiocarcinoma (ICC).MethodsThis study retrospectively enrolled 110 patients with pathologically confirmed ICC lesions who were subject to preoperative contrast-enhanced ultrasound (CEUS) examinations between January 2022 and February 2023. Patients were further classified according to the subtype: SD-type and LD-type, and an optimal predictive model was established and validated using the above pilot cohort. The test cohort, consisting of 48 patients prospectively enrolled from March 2023 to September 2023, was evaluated.ResultsIn the pilot cohort, compared with SD-type ICCs, more LD-type ICCs showed elevated carcinoembryonic antigen (p < 0.001), carbohydrate antigen 19-9 (p = 0.004), ill-defined margin (p = 0.018), intrahepatic bile duct dilation (p < 0.001). Among DCE-US quantitative parameters, the wash-out area under the curve (WoAUC), wash-in and wash-out area under the curve (WiWoAUC), and fall time (FT) at the margin of lesions were higher in the SD-type group (all p < 0.05). Meanwhile, the mean transit time (mTT) and wash-out rate (WoR) at the margin of the lesion were higher in the LD-type group (p = 0.041 and 0.007, respectively). Logistic regression analysis showed that intrahepatic bile duct dilation, mTT, and WoR were significant predictive factors for predicting ICC subtypes, and the AUC of the predictive model achieved 0.833 in the test cohort.ConclusionsPreoperative DCE-US has the potential to become a novel complementary method for predicting the pathological subtype of ICC.Critical relevance statementDCE-US has the potential to assess the subtypes of ICC lesions quantitatively and preoperatively, which allows for more accurate and objective differential diagnoses, and more appropriate treatments and follow-up or additional examination strategies for the two subtypes.Key PointsPreoperative determination of intrahepatic cholangiocarcinoma (ICC) subtype aids in surgical decision-making.Quantitative parameters from dynamic contrast-enhanced US (DCE-US) allow for the prediction of the ICC subtype.DCE-US-based imaging has the potential to become a novel complementary method for predicting ICC subtypes.Graphical

HK2 promotes migration and invasion of intrahepatic cholangiocarcinoma via enhancing cancer stem-like cells' resistance to anoikis

Cancer stem-like cells (CSLCs) and anoikis resistance play crucial roles in the metastasis of cancers. However, it remains unclear whether CSLCs are related to anoikis resistance in intrahepatic cholangiocarcinoma (ICC). Here we identified a group of stemness-related anoikis genes (SRAGs) via bioinformatic analysis of public data. Accordingly, a novel anoikis-related classification was established and it divided ICC into C1 and C2 type. Different type ICC displayed distinct prognosis, molecular as well immune characteristics. Furthermore, we found one key SRAGs via several machine learning algorithms. HK2 was up-regulated in tumor-repopulating cells (TRCs) of ICC, a kind of CSLCs with a potent resistance to anoikis. Its up-regulation may be caused by the activation of MTORC1 signaling in ICC-TRCs. And inhibition of HK2 significantly increased anoikis and decreased migration as well invasion in ICC-TRCs. Our studies provide an insight into the molecular mechanism underlying the resistance of ICC-TRCs to anoikis and enhance the evidences for targeting HK2 in ICC.

Bile duct adenoma and small-sized small duct type intrahepatic cholangiocarcinoma show distinct differences in genetic alterations, expression of IMP3 and EZH2 and stromal and inflammatory components.

Given that bile duct adenoma was significantly more prevalent in the liver with small duct type intrahepatic cholangiocarcinoma (small duct iCCA), compared to other primary liver carcinomas, we examined the possibility of bile duct adenoma as a precursor of small duct iCCA by analysing genetic alterations and other features in bile duct adenomas. Subjects included 33 bile duct adenomas and 17 small-sized (up to 2 cm in diameter) small duct iCCAs. Genetic alterations were examined by direct sequencing for hot-spot regions and immunohistochemical staining. The expression of p16INK4a , EZH2 and IMP3 and stromal and inflammatory components were also examined. Genetic alterations examined including BRAF were not detected in bile duct adenomas, whereas genetic alterations of p53 (47%), ARID1A (41%), PBRM1 (12%), MTAP (12%), IDH1 (6%), KRAS (6%) and TERT promoter (6%) were detected in 16 small-sized small duct iCCA (94%) (P < 0.01). The expression of IMP3 and EZH2 was not detected in bile duct adenomas, whereas it was detected in most small duct iCCA (94%) (P < 0.01). Immature stroma and neutrophilic infiltration were significantly more prevalent in small duct iCCA, compared to bile duct adenoma (P < 0.01). Bile duct adenomas and small-sized small duct iCCAs show distinct differences in genetic alterations, expression of IMP3 and EZH2 and stromal and inflammatory components. There was no evidence suggesting that bile duct adenoma is a precursor of small duct iCCA. Immunohistochemical staining for IMP3, EZH2, p53, ARID1A and MTAP may be useful for differential diagnosis between bile duct adenomas and small duct iCCAs.

Clinicopathological, etiological and molecular characteristics of intrahepatic cholangiocarcinoma subtypes classified by mucin production and immunohistochemical features

ABSTRACTBackgroundIntrahepatic cholangiocarcinoma (ICC) can be divided into two morphological subtypes: large duct type and small duct type ICC. This study aims to verify the feasibility of the classification criteria and clinicopathological characteristics of ICC.Research design and methodsICC patients were divided into the large and small type ICC by morphological and immunohistochemical patterns. Subsequently, clinicopathological data of the two groups was compared and the multivariate COX regression was used to verify the clinical significance of ICC subtypes. In addition, IDH1/2 mutation, KRAS mutation and FGFR2 translocation was also evaluated.ResultsTotally, 32, 61 and 13 tumors were defined as large, small and the indeterminate-duct type ICC respectively. Clinicopathologically, the large and small duct type ICC showed distinct morphological features. Compared with the small duct type ICC, the large duct type ICC had higher levels of serum tumor markers, vascular invasion, lymph node metastasis, and postoperative recurrence. Furthermore, positive FGFR2 rearrangement occurred only in small duct type ICC and IDH1/2 was mutated mainly in small duct type ICC.ConclusionsThe subclassification system was applicable and the ICC subtypes had distinct clinicopathological characteristics, prognostic outcome, and IDH1/2 mutation pattern.

The impact of tumor location on the value of lymphadenectomy for intrahepatic cholangiocarcinoma

BackgroundThe therapeutic role of lymphadenectomy (LND) for intrahepatic cholangiocarcinoma (ICC) patients remains ill-defined. We sought to analyze the therapeutic value of LND relative to tumor location and preoperative lymph node metastasis (LNM) risk. MethodsPatients who underwent curative-intent hepatic resection of ICC between 1990 and 2020 were included from a multi-institutional database. Therapeutic LND (tLND) was defined as LND that harvested ≥3 lymph nodes. ResultsAmong 662 patients, 178 (26.9%) individuals received tLND. Patients were categorized into central type ICC (n = 156, 23.6%) and peripheral type ICC (n = 506, 76.4%). Central type harbored multiple adverse clinicopathologic factors and worse overall survival (OS) compared with peripheral type (5-year OS, central: 27.0% vs. peripheral: 47.2%, p < 0.001). After consideration of preoperative LNM risk, patients with central type and high-risk LNM who underwent tLND survived longer than individuals who did not (5-year OS, tLND: 27.9% vs. non-tLND: 9.0%, p = 0.001), whereas tLND was not associated with better survival among patients with peripheral type ICC or low-risk LNM. The therapeutic index of hepatoduodenal ligament (HDL) and other regions was higher in central type than in peripheral type, which was more pronounced among high-risk LNM patients. ConclusionsCentral type ICC with high-risk LNM should undergo LND involving regions beyond the HDL.

两种不同分型肝内胆管癌临床病理特征及预后分析

两种不同分型肝内胆管癌临床病理特征及预后分析

Molecular profile and its clinical impact of IDH1 mutated versus IDH1 wild type intrahepatic cholangiocarcinoma

IDH1-mutated cholangiocarcinomas (CCAs) are an interesting group of neoplasia with particular behavior and therapeutic implications. The aim of the present work is to highlight the differences characterizing IDH1m and IDH1wt CCAs in terms of genomic landscape. 284 patients with iCCA treated for resectable, locally advanced or metastatic disease were selected and studied with the FOUNDATION Cdx technology. A comparative genomic analysis and survival analyses for the most relevant altered genes were performed between IDH1m and IDH1wt patients. Overall, 125 patients were IDH1m and 122 IDH1wt. IDH1m patients showed higher mutation rates compared to IDH1wt in CDKN2B and lower mutation rates in several genes including TP53, FGFR2, BRCA2, ATM, MAP3K1, NOTCH2, ZNF703, CCND1, NBN, NF1, MAP3KI3, and RAD21. At the survival analysis, IDH1m and IDH1wt patients showed no statistically differences in terms of survival outcomes, but a trend in favor of IDH1wt patients was observed. Differences in prognostic values of the most common altered genes were reported. In surgical setting, in IDH1m group the presence of CDKN2A and CDKN2B mutations negatively impact DFS, whereas the presence of CDKN2A, CDKN2B, and PBRM1 mutations negatively impact OS. In advanced setting, in the IDH1m group, the presence of KRAS/NRAS and TP53 mutations negatively impact PFS, whereas the presence of TP53 and PIK3CA mutations negatively impact OS; in the IDH1wt group, only the presence of MTAP mutation negatively impact PFS, whereas the presence of TP53 mutation negatively impact OS. We highlighted several molecular differences with distinct prognostic implications between IDH1m and IDH1wt patients.

Quantitative Proteomics Reveals Down-Regulated Glycolysis/Gluconeogenesis in the Large-Duct Type Intrahepatic Cholangiocarcinoma.

Intrahepatic cholangiocarcinoma (iCCA) is a lethal hepatobiliary malignancy that arises from the epithelial cells of the intrahepatic bile ducts, accounting for approximately 10% of cholangiocarcinoma (CCA). According to the 2019 World Health Organization (WHO) classification of tumors of the digestive system, iCCA is divided into small-duct type (SD-type) and large-duct type (LD-type). However, it remains unknown which molecular events contribute to the disparity. To explore the proteomic characteristics of iCCA, we used an isobaric tag for relative and absolute quantitation (iTRAQ) based quantitative proteomics strategy to investigate stably dysregulated proteins in the SD-type and LD-type of iCCA tissues. Importantly, we found three glycolysis/gluconeogenesis-related enzymes, triosephosphate isomerize 1 (TPI1), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and phosphoglycerate kinase 1 (PGK1), were significantly down-regulated in the LD-type iCCA, which were further confirmed by immunohistochemistry using tissue microarray. Moreover, we demonstrated that the knockdown of these three candidate proteins by siRNAs notably increased the ability of proliferation in two CCA cell lines (HuH28 and RBE), suggesting that effective down-regulation of the glycolysis/gluconeogenesis pathway might be an underlying novel mechanism contributing to the LD-type iCCA.

SUOX and GLUT1 are biomarkers for the prognosis in large duct type intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (iCCA) is the second most common hepatic malignant disease and has a poor prognosis, but few biomarkers have been found. SUOX is an important factor in energy metabolism and a poor prognostic factor in other malignancies. In this study, we aimed to clarify the relationship between SUOX and GLUT expression in large duct type iCCA and the mechanism of mitochondrial energy metabolism in iCCA. We evaluated SUOX and GLUT1 expression in 96 large duct type iCCA cases and proportion score (PS) was used to evaluate the expression; receiver operating characteristic (ROC) curves of both SUOX and GLUT1 expression were generated, and the Kaplan-Meier method and Cox regression analysis were used to estimate overall survival. Of the 96 iCCA cases, 73 (76.0%) showed low SUOX expression and 66 (68.8%) showed high GLUT1 expression. The 5-year survival rate of iCCA with low SUOX expression was significantly shorter than that of iCCA with high SUOX expression (p=0.001). In contrast, the 5-year survival rate of iCCA with high GLUT1 expression was significantly shorter than that of iCCA with low GLUT1 expression (p=0.005). According to Spearman's correlation, there was no correlation between SUOX and GLUT1. Conversely, the combination of low SUOX and high GLUT1 expression was the most common in 51 of 96 cases (53.1%), and the overall survival was significantly shorter than that of patients with other combinations. Furthermore, SUOX was shown to be an independent prognostic factor together with GLUT1, suggesting that SUOX in combination with GLUT1 can predict the prognosis of large duct type iCCA.

Predicting prognosis and evaluating the benefits of adjuvant chemotherapy depending on the tumor location in intrahepatic cholangiocarcinoma: focusing on the involvement of below 2nd bile duct confluence.

PurposeIntrahepatic cholangiocarcinoma (ICC) has various characteristics according to anatomical, histologic classifications, and its prognoses are different. This study aimed to compare oncologic outcomes according to tumor location (second bile duct confluence) and evaluate the effect of adjuvant chemotherapy.MethodsClinical data of 318 patients who underwent curative resection for ICC was reviewed. Central type ICC (C-ICC) and peripheral type ICC (P-ICC) were defined when the tumor invades the intrahepatic secondary biliary confluence and when located more peripherally, respectively.ResultsA larger tumor size, higher rate of elevated CA 19-9 level, vascular invasion, R1 resection, advanced T stage, and lymph node metastasis were found in C-ICC. C-ICC had poorer overall survival (median, 33 months vs. 58 months; P = 0.001), and the difference was more prominent in the early stage. C-ICC had a higher recurrence rate (68.7% vs. 55.1%, P = 0.014); otherwise, there was no difference in the recurrence patterns. There were no survival benefits of adjuvant chemotherapy in the entire cohort, but there were benefits in advanced stages (T3–4, N1 stage), especially in C-ICC.ConclusionC-ICC has more aggressive tumor characteristics and poor survival compared to P-ICC. Adjuvant chemotherapy seems to have survival benefits in the advanced stages, especially in the central type.

Development and Validation of a Nomogram Model to Predict the Prognosis of Intrahepatic Cholangiocarcinoma

Background: The effective method for predicting prognosis of ICC is still lack. This study aims to establish and verify an effective prognostic nomogram model for intrahepatic cholangiocarcinoma (ICC) after partial hepatectomy. Materials and Methods: A nomogram model was developed in a cohort of 127 patients from January 2015 to December 2019. General clinical characteristics including preoperative physical examination data and postoperative pathological features were obtained. The independent risk factors identified by univariate and multivariate COX proportional hazards regression models were used to construct nomogram model. Predictive accuracy and discriminative ability were determined using a concordance index and a calibration curve. In addition, the clinical significance of postoperative pathological subtypes was analyzed by Kaplan-Meier survival analysis. Results: Univariate analysis and multivariate COX regression analysis revealed that CEA, maximum diameter, tumor number, and large duct type ICC was the independent risk factors. These variables were incorporated into the nomogram and the C-index for one year and three year overall survival prediction was 0.765 (95% CI: 0.672–0.814) and 0.695 (95% CI: 0.672–0.814), respectively. Postoperative pathological analysis showed that the large duct ICC had a distinct clinicopathological features and poor outcome. Conclusion: The proposed nomogram enables a prognostic prediction for patients with ICC and postoperative subclassification of ICC is of great significant to the prognosis of ICC.

Molecular Characterization of Biliary Tract Cancer Predicts Chemotherapy and Programmed Death 1/Programmed Death-Ligand 1 Blockade Responses.

Biliary tract cancer (BTC) exhibits diverse molecular characteristics. However, reliable biomarkers that predict therapeutic responses are yet to be discovered. We aimed to identify the molecular features of treatment responses to chemotherapy and immunotherapy in BTCs. We enrolled 121 advanced BTC patients (68 cholangiocarcinomas [33 intrahepatic, 35 extrahepatic], 41 gallbladder cancers, and 12 Ampulla of Vater cancers) whose specimens were analyzed by clinical sequencing platforms. All patients received first-line palliative chemotherapy; 48 patients underwent programmed death 1 (PD-1)/programmed death-ligand 1 (PD-L1) blockade therapy after failed chemotherapy. Molecular and histopathological characterization was performed using targeted sequencing and immunohistochemical staining to investigate treatment response-associated biomarkers. Genomic analysis revealed a broad spectrum of mutational profiles according to anatomical location. Favorable responses to chemotherapy were observed in the small-duct type compared with the large-duct type intrahepatic cholangiocarcinoma, with frequent mutations in BRCA1-associated protein-1/isocitrate dehydrogenase 1/2 and KRAS proto-oncogene, GTPase/SMAD family member 4 genes, respectively. The molecular features were further analyzed in BTCs, and transforming growth factor beta and DNA damage response pathway-altered tumors exhibited poor and favorable chemotherapy responses, respectively. In PD-1/PD-L1 blockade-treated patients, KRAS alteration and chromosomal instability tumors were associated with resistance to immunotherapy. The majority of patients (95.0%) with these resistance factors show no clinical benefit to PD-1/PD-L1 blockade and low tumor mutational burdens. Low tumor-infiltrating lymphocyte (TIL) density in tumors with these resistance factors indicated immune-suppressive tumor microenvironments, whereas high intratumoral TIL density was associated with a favorable immunotherapy response. This study proposes predictive molecular features of chemotherapy and immunotherapy responses in advanced BTCs using clinical sequencing platforms. Our result provides an intuitive framework to guide the treatment of advanced BTCs benefiting from therapeutic agents based on the tumors' molecular features.

Clinical implication of tumor location in intrahepatic cholangiocarcinoma and assessment of the current staging system

Intrahepatic cholangiocarcinoma (ICC) exhibits a variety of morphologic and histologic growth pattern, and its treatment and prognosis are known to vary depending on the location and extent of tumor. This study aims to compare the clinical data according to the tumor location in ICC and to verify the current staging system used in ICC. 302 patients who underwent curative resection were reviewed. Central type ICC (C-ICC) was defined when the tumor had an invasion of intrahepatic secondary confluence or segmental branches of the bile duct and peripheral type ICC (P-ICC) when the tumor was located more peripherally. Clinicopathologic characteristics, oncological outcomes, and prognostic stratification of the AJCC 8th staging system were assessed. Among 302 patients, 123 were classified as C-ICC and 179 as P-ICC. Bigger tumor size, higher rate of elevated CA19-9 level, vascular invasion, periductal invasion type, R1 rate, and advanced T stage was found in C-ICC. Five-year overall survival rates were 34.0% for C-ICC and 47.5% for P-ICC (p = 0.005). A significant difference in disease-free survival was seen as well (p = 0.036). The prognostic utility of ICC T stage was assessed in N0 C-ICC but failed to stratify T2, T3, and T4 tumors (median survival; T2: 37 m. T3: 34 m. T4: 33 m. p = 0.591). When applying the perihilar cholangiocarcinoma staging system (p < 0.001), stratification was improved and similar results were also seen in the overall staging. C-ICC has a worse aggressive clinical course compared to P-ICC. The perihilar cholangiocarcinoma cancer staging system is better than ICC staging to stratify the prognosis of C-ICC.

Impact of hepatitis C virus on survival in patients undergoing resection of intrahepatic cholangiocarcinoma: Report of a Japanese nationwide survey.

We reviewed the data of a nationwide follow-up survey to determine the impact of hepatitis C virus (HCV) infection on the outcomes of hepatectomy for mass-forming (MF) type, and combined mass-forming and periductal infiltrating (MF+PI) type intrahepatic cholangiocarcinoma (ICC). In total, 956 patients with ICC who underwent curative hepatic resection were included in this cohort study, and patients were classified according to virus status. Patients were classified according to virus status as follows: HCV-related ICC (n=138, 14.4%), hepatitis B virus (HBV)-related ICC (n=43, 4.5%) and non-virus-related ICC (n=775, 81.1%). To control for variables, we used 1:1 propensity score-matching to compare outcomes after surgery between HCV-related (n=102) and non-virus-related ICC cases (n=102). We successfully matched HCV-related and non-virus-related ICC cases with similar liver function and tumor characteristics. Patients with HCV-related ICC had significantly shorter recurrence-free survival (hazard ratio 0.62, 95% confidence interval 0.42-0.92, p=0.016) and overall survival (hazard ratio: 0.57, 95% confidence interval: 0.37-0.88, p=0.011) than patients with non-virus-related ICC. Cox proportional hazard analysis showed that HCV-related ICC offered a worse prognosis than non-virus-related ICC. HCV infection increases the risk of recurrence and worsens overall survival in patients after curative resection for MF and combined MF+PI type ICC.

Prognostic Value of Inflammatory and Tumour Markers in Small-Duct Subtype Intrahepatic Cholangiocarcinoma after Curative-Intent Resection

Intrahepatic cholangiocarcinoma (ICC) is characterised by heterogeneity, and it can be subdivided into small-duct and large-duct types. Inflammatory and tumour markers could effectively predict prognosis in many cancers, but no similar studies have been conducted in the histological subtypes of ICC. A total of 102 and 72 patients with ICC undergoing curative-intent resection were retrospectively subclassified into large-duct and small-duct types by chemical staining, respectively. The prognostic value of inflammatory and tumour markers was studied for the first time in histological subtypes of ICC by using a Cox regression model. A novel predictor named prognostic inflammatory index (PII) was proposed and defined as neutrophil × monocyte/lymphocyte count (109/L). Survival analysis showed that PII, neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA19-9), CA242, and ferritin were all predictors of DFS and OS in patients with ICC (P < 0.040). Subgroup analysis showed that PII, CA19-9, and ferritin were risk predictors of disease-free survival (DFS) and overall survival (OS) in small-duct type ICC (P < 0.015). In addition, in small-duct type ICC, NLR and LMR were correlated with OS (P < 0.025), whilst CEA and CA242 were correlated with DFS (P ≤ 0.010). In conclusion, PII is a convenient and efficient inflammatory predictor of DFS and OS in ICCs and their small-duct type. NLR and LMR, rather than platelet-to-lymphocyte ratio, were correlated with OS in small-duct type ICC. In addition, ferritin may be a supplement to CA19-9 in stratifying the survival outcome of patients with small-duct type ICC.

Different iron-handling in inflamed small and large cholangiocytes and in small and large-duct type intrahepatic cholangiocarcinoma.

Cholangiocarcinoma (CCA) represents the second most common primary hepatic malignancy and originates from the neoplastic transformation of the biliary cells. The intrahepatic subtype includes two morpho-molecular forms: large-duct type intrahepatic CCA (iCCA) and small-duct type iCCA. Iron is fundamental for the cellular processes, contributing in tumor development and progression. The aim of this study was to evaluate iron uptake, storage, and efflux proteins in both lipopolysaccharide-inflamed small and large cholangiocytes as well as in different iCCA subtypes. Our results show that, despite an increase in interleukin-6 production by both small and large cholangiocytes, ferroportin (Fpn) was decreased only in small cholangiocytes, whereas transferrin receptor-1 (TfR1) and ferritin (Ftn) did not show any change. Differently from in vitro models, Fpn expression was increased in malignant cholangiocytes of small-duct type iCCA in comparison to large-duct type iCCA and peritumoral tissues. TfR1, Ftn and hepcidin were enhanced, even if at different extent, in both malignant cholangiocytes in comparison to the surrounding samples. Lactoferrin was higher in large-duct type iCCA in respect to small-duct type iCCA and peritumoral tissues. These findings show a different iron handling by inflamed small and large cholangiocytes, and small and large-duct type iCCA. The difference in iron homeostasis by the iCCA subtypes may have implications for the tumor management.

Bile duct adenoma may be a precursor lesion of small duct type intrahepatic cholangiocarcinoma.

Precursor lesions of small duct type intrahepatic cholangiocarcinoma (small duct iCCA) have not been clarified so far. We hypothesised that precursor lesions may be frequently distributed in the background liver of small duct iCCA. We determined by histology the presence of bile duct adenomas and von Meyenburg complexes as candidate precursor lesions in the background liver of small duct iCCA, with other primary liver carcinomas as control. Subjects included 28 patients with small duct iCCA, 29 with large duct iCCAs, 60 with combined hepatocellular-cholangiocarcinoma (Comb) and 40 with hepatocellular carcinoma (HCC). The prevalence of bile duct adenomas in the background liver was significantly higher in small duct iCCA (35.7%) compared to other primary liver carcinomas (Comb, 4.9%; 10%, HCC) (P<0.01). The prevalence of bile duct adenomas was significantly associated with the presence of von Meyenburg complexes and ductal plate malformation-like patterns in small duct iCCAs and Combs. Von Meyenburg complexes were detected in 11 small duct iCCA (39.3%), five large duct iCCAs (17.2%), 10 Comb (16.4%) and 13 HCC (33.3%), respectively (P>0.05). Small duct iCCAs showed altered expression of ARID1A (46.4%), p53 (39.3%), PBRM1 (14.3%), IMP3 (85.7%) and EZH2 (82.1%), whereas these markers were negative in bile duct adenomas. Bile duct adenomas may be precursor lesions of small duct iCCAs. Alteration of ARID1A, p53 or PBRM1 may be involved in the carcinogenesis of small duct iCCAs.

Abstract 3627: Comparison of genetic profiles of small and large duct type intrahepatic cholangiocarcinoma with distal extrahepatic cholangiocarcinoma

Abstract Cholangiocarcinoma comprises epithelial malignancy that occurs in various sites in the biliary tree. Cholangiocarcinoma is categorized into intrahepatic, perihilar, and distal bile duct carcinomas according to its anatomical position. According to the fifth edition of World Health Organization Classification of Tumors, intrahepatic cholangiocarcinoma (ICC) is further classified into small- and large duct types on histopathological basis. We analyzed molecular profiles of different types of cholangiocarcinoma by next-generation sequencing (NGS). We utilized the Oncomine Comprehensive Assay (OCA) panel v2 on the IonTorrent™ NGS platform to explore genetic differences among the two histologic types of ICC and distal extrahepatic cholangiocarcinoma (DEC). Formalin-fixed paraffin-embedded tumor tissues were obtained from 25 patients who underwent surgical resection of cholangiocarcinoma in Korea University Guro Hospital between 2010 and 2018. We analyzed 7 and 8 small- and large duct type ICCs and 10 DECs. NGS assay of the included cases showed distinct genetic alterations between ICC and DEC, which were enriched in different biological pathways. Unsupervised hierarchical clustering analysis showed two distinct groups. The first group consisted of 12 cases (9 DECs and 3 large duct type ICCs). The second group included 13 cases (7 large duct type and 6 small duct type ICCs). Molecular alteration patterns of a subset of large duct type ICCs were more closely related to DECs than small duct type ICCs. All included small duct type ICCs were considered genetically distinct from DECs. Our study suggested an association between anatomical and histopathological classifications of intra- and extrahepatic cholangiocarcinomas. Citation Format: Hayeon Kim, Soo Yeon Lee, Aeree Kim, Baek-hui Kim, Chung-yeul Kim. Comparison of genetic profiles of small and large duct type intrahepatic cholangiocarcinoma with distal extrahepatic cholangiocarcinoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3627.

Distinct clinical and prognostic implication of IDH1/2 mutation and other most frequent mutations in large duct and small duct subtypes of intrahepatic cholangiocarcinoma

BackgroundIsocitrate dehydrogenase 1/2 (IDH1/2), BAP1, ARID1A and PBRM1 have been reported as the most frequent mutant genes in intrahepatic cholangiocarcinoma (ICC), and their relationships with clinicopathological features and prognosis were researched in this study.MethodsWe collected clinical data of 130 ICC patients from January 2012 to December 2017. The IDH1/2 mutation and loss of BAP1, ARID1A and PBRM1 expressions were detected by DNA sequencing or immunohistochemical methods, and histological subtype of ICCs was determined by hematoxylin-eosin, Alcian blue and S100P staining.ResultsIDH1/2 mutation was related to decreased preoperative serum total bilirubin (P = 0.039), ferritin (P = 0.000) and higher histological differentiation (P = 0.024), and was associated with prolonged disease-free survival (P = 0.009) and a trend toward increased overall survival (P = 0.126) in small duct type of ICCs. Immunohistochemical staining results of MsMab-1 were generally consistent with DNA sequencing for IDH1/2 mutant in ICCs (κ = 0.691). Only BAP1 expression loss was correlated to prolonged disease-free survival (P = 0.031) and overall survival (P = 0.041) in large duct type of ICCs.ConclusionsIDH1/2 mutation is a favorable predictor and may be related to iron metabolism in small duct type of ICCs. Furthermore, we suggest that the detection of IDH1/2 mutation is indispensable to determine targeted therapy in small duct type ICCs, while it is not necessary in large duct of ICCs. MsMab-1 is a relatively effective multi-specific antibody against IDH1/2 mutant in ICCs. BAP1 expression loss was correlated with improved prognosis only in large duct type ICCs.