Background: The mismatch repair (MMR) system prevents DNA mutation; therefore, deficient MMR protein (dMMR) expression causes genetic alterations and microsatellite instability (MSI). dMMR is correlated with a good outcome and treatment response in various cancers; however, the situation remains ambiguous in cholangiocarcinoma (CCA). This study aims to evaluate the prevalence of dMMR and investigate the correlation with clinicopathological features and the survival of CCA patients after resection. Materials and Methods: Serum and tissues were collected from CCA patients who underwent resection from January 2005 to December 2017. Serum OV IgG was examined using ELISA. The expression of MMR proteins MLH1, MSH2, MSH6 and PMS2 was investigated by immunohistochemistry; subsequently, MMR assessment was evaluated as either proficient or as deficient by pathologists. The clinicopathological features and MMR status were compared using the Chi-square test. Univariate and multivariate analyses were conducted to identify prognostic factors. Results: Among the 102 CCA patients, dMMR was detected in 22.5%. Survival analysis revealed that dMMR patients had better survival than pMMR (HR = 0.50, p = 0.008). In multivariate analysis, dMMR was an independent factor for a good prognosis in CCA patients (HR = 0.58, p = 0.041), especially at an early stage (HR = 0.18, p = 0.027). Moreover, subgroup analysis showed dMMR patients who received adjuvant chemotherapy had better survival than surgery alone (HR = 0.28, p = 0.012). Conclusion: This study showed a high prevalence of dMMR in cholangiocarcinoma with dMMR being the independent prognostic factor for good survival, especially in early-stage CCA and for patients who received adjuvant chemotherapy. dMMR should be the marker for selecting patients to receive a specific adjuvant treatment after resection for CCA.

Background and Objectives: Gallbladder cancer (GBC) is a biologically aggressive malignancy characterised by poor survival outcomes often attributed to delayed diagnosis due to nonspecific clinical presentations. Paraneoplastic syndromes (PNSs), atypical symptoms caused by cancer itself, may serve as valuable indicators for timely diagnosis, particularly in malignancies with nonspecific features. Understanding the manifestations of PNSs in GBC is, therefore, critical. This systematic review collates case studies documenting the association of PNS with GBC, including subsequent management and clinical outcomes. Materials and Methods: A comprehensive search of PubMed, Embase, CINAHL, Web of Science, and Cochrane Library databases yielded 49 relevant articles. Upon searching other information sources, two more relevant articles were identified via citation sources. Results: The paraneoplastic syndromes were classified according to haematological (leukocytosis), dermatological (inflammatory myositis like dermatomyositis and polymyositis, acanthosis nigricans, Sweet’s syndrome, exfoliative dermatitis), neurological, metabolic (hypercalcemia, hyponatremia), and others (chorea). The analysis included the age, sex, and country of origin of the patient, as well as the time of PNS diagnosis relative to GBC diagnosis. Furthermore, common presenting complaints, investigations, and effectiveness of treatment modalities using survival time were assessed. Conclusions: While PNS management can offer some benefits, oncologic outcomes of GBC are largely poor. The majority of PNS in GBC are reported in advanced stages, and, hence, PNS has a minimal role in early diagnosis. PNS management can improve a patient’s quality of life, and thus recognition and treatment are important considerations in the holistic management of GBC patients.

Background/Objectives: Post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP) is a frequent but insufficiently studied complication in cholangiocarcinoma (CCA). This study aimed to evaluate incidence and risk factors of PEP in CCA. Methods: We retrospectively reviewed 148 CCA patients who underwent ERCP between 2019 and 2022. Demographic, clinical, and procedural data were compared between patients with and without PEP, and logistic regression was used to identify independent predictors. Results: PEP occurred in 26.4% of patients, mostly aged ≥ 66 years, male, and with perihilar CCA. In PEP cases, metallic stents were frequently used, procedures often exceeded 60 min, and 28.2% developed post-ERCP cholangitis. Hospital stay was ≥4 days in nearly 90% of cases. PEP severity was mild (10.3%), moderate (61.5%), and severe (28.2%). Multivariate analysis showed older age, metallic stent placement, and post-ERCP cholangitis as independent risk factors, while bilirubin ≥ 15 mg/dL was protective. Conclusions: PEP occurred in over one-fourth of CCA patients, predominantly of moderate severity. Independent risk factors included older age, metallic stent placement, and post-ERCP cholangitis, whereas bilirubin ≥ 15 mg/dL was protective. Awareness of these factors may aid risk stratification and prevention in this high-risk group.

Background: Cholangiocarcinoma (CCA) has the highest incidence in Northeastern Thailand, where patients generally present with late diagnosis and poor prognosis. Opisthorchis viverrini (OV) infection is the major cause of CCA, with oxidative stress driving DNA mutations and genetic instability. Microsatellite instability (MSI) is a predictive biomarker in several cancers. This study aimed to investigate MSI status and its association with clinicopathological features and survival of CCA patients. Methods: Tissue and serum samples were collected from 25 surgical CCA patients. MSI status and mismatch repair (MMR) proteins were evaluated using an MSI scanner and immunohistochemistry (IHC). Serum OV IgG was assessed by ELISA, while tumor-infiltrating lymphocytes (TILs) were evaluated by two pathologists. Associations of MSI with clinicopathological features, OV status, MMR, and survival were analyzed. Results: Among CCA patients, 66.7% were MSI-high and 33.3% were MSI-low. MSI-high significantly correlated with age < 57 years, intraductal growth pattern, OV positivity, and early-stage disease. Patients with MSI-high and high TILs showed markedly improved median survival compared to MSI-low with low TILs (94.0 vs. 16.8 and 3.0 months; HR = 6.82 and 14.10; p = 0.004 and 0.001). Incorporation of MSI and TILs remained an independent prognostic factor in multivariate analysis (p < 0.05). Conclusions: MSI-high is highly prevalent in OV-associated CCA and is associated with intraductal growth, OV infection, and early-stage disease. Combined MSI and TIL status may serve as an independent prognostic factor, warranting validation in larger cohorts.

Cholangiocarcinoma (CCA) in Northeast Thailand is characterized by late diagnosis and poor prognosis, creating a critical need for effective early-detection biomarkers. This study utilized a multi-omics approach to identify novel diagnostic targets and improve CCA screening. Initial serum proteomic and transcriptomic analyses revealed significant upregulation of the luteinizing hormone/choriogonadotropin receptor (LHCGR) in CCA patients, correlating with advanced disease stages. Interaction network analysis subsequently identified its circulating ligand, beta-human chorionic gonadotropin (β-hCG), as a highly translatable clinical target. The protein expression of β-hCG was assessed via immunohistochemistry (IHC) in 100 tissue samples, and serum levels of β-hCG, alongside routine markers (CA19-9, AFP, and CEA), were quantified in a cohort of 405 individuals, including 153 CCA patients. IHC confirmed significantly higher β-hCG expression in tumor tissues compared to adjacent areas (p < 0.0001). Serum β-hCG levels were significantly elevated in CCA patients and correlated with tumor volume and reduced overall survival. Diagnostically, a combined multiparameter panel (β-hCG, carbohydrate antigen 19-9, carcinoembryonic antigen, and alpha-fetoprotein) yielded excellent accuracy in distinguishing CCA from healthy controls (AUC: 0.962) and hepatocellular carcinoma cases (AUC: 0.890). However, discriminatory efficiency was notably lower when differentiating CCA from benign biliary diseases (AUC: 0.680) and liver metastases (AUC: 0.705). In conclusion, activation of the LHCGR signaling axis is a novel pathophysiological feature in CCA. When integrated into a multi-marker blood panel, circulating β-hCG serves as a valuable complementary risk-stratification and prognostic tool, though further optimization is required to overcome limited specificity in the presence of confounding liver pathologies before routine clinical implementation.