Preoperative predictors for non-resectability in perihilar cholangiocarcinoma.

INTRODUCTION: Explorative laparotomy without subsequent curative-intent liver resection remains a major clinical problem in the treatment of perihilar cholangiocarcinoma (pCCA). Thus, we aimed to identify preoperative risk factors for non-resectability of pCCA patients. MATERIAL AND METHODS: Patients undergoing surgical exploration between 2010 and 2022 were eligible for the analysis. Separate binary logistic regressions analyses were used to determine risk factors for non-resectability after explorative laparotomy due to technical (tumor extent, vessel infiltration) and oncological (peritoneal carcinomatosis, distant nodal or liver metastases)/liver function reasons. RESULTS: This monocentric cohort comprised 318 patients with 209 (65.7%) being surgically resected and 109 (34.3%) being surgically explored [explorative laparotomy: 87 (27.4%), laparoscopic exploration: 22 (6.9%)]. The median age in the cohort was 69 years (range 60-75) and a majority had significant comorbidities with ASA-Score ≥ 3 (202/318, 63.5%). Statistically significant (p < 0.05) risk factors for non-resectability were age above 70 years (HR = 3.76, p = 0.003), portal vein embolization (PVE, HR = 5.73, p = 0.007), and arterial infiltration > 180° (HR = 8.05 p < 0.001) for technical non-resectability and PVE (HR = 4.67, p = 0.018), arterial infiltration > 180° (HR = 3.24, p = 0.015), and elevated CA 19-9 (HR = 3.2, p = 0.009) for oncological/liver-functional non-resectability. CONCLUSION: Advanced age, PVE, arterial infiltration, and elevated CA19-9 are major risk factors for non-resectability in pCCA. Preoperative assessment of those factors is crucial for better therapeutical pathways. Diagnostic laparoscopy, especially in high-risk situations, should be used to reduce the amount of explorative laparotomies without subsequent liver resection.

Time to surgery is not an oncological risk factor in patients with cholangiocarcinoma undergoing curative-intent liver surgery.

Surgical resection is the only option to achieve long-term survival in cholangiocellular carcinoma (CCA). Due to limitations of health care systems and unforeseeable events, e.g., the COVID pandemic, the time from diagnosis to surgery (time-to-surgery (TTS)) has gained great interest in malignancies. Thus, we investigated whether TTS is associated with the oncological outcome in patients who underwent surgery for CCA. A cohort of 276 patients undergoing curative-intent surgery for intrahepatic and perihilar CCA excluding individuals with neoadjuvant therapy and perioperative mortality between 2010 and 2021 were eligible for analysis. Patients were grouped according to TTS (≤ 30; 31-60; 61-90; > 90 days) and compared by Kruskal-Wallis-analysis. Survival was compared using Kaplan-Meier analysis and characteristics associated with cancer-specific survival (CSS), recurrence-free survival (RFS) and overall survival (OS) using Cox regressions. The median CSS was 39 months (3-year-CSS = 52%, 5-year-CSS = 42%) and the median RFS 20 months (3-year-CSS = 38%, 5-year-CSS = 33%). In univariable Cox regressions, TTS was not associated with CSS (p = 0.971) or RFS (p = 0.855), respectively. A grouped analysis with respect to TTS (≤ 30 days, n = 106; 31-60 days, n = 134; 61-90 days, n = 44; > 90 days, n = 29) displayed a median CSS of 38, 33, 51 and 41 months and median RFS of 17, 22, 28 and 20 months (p = 0.971 log rank; p = 0.520 log rank). No statistical difference regarding oncological risk factors were observed between the groups. This study is the first comprehensive analysis of TTS in CCA patients. Within a representative European cohort, TTS was not associated with earlier tumor recurrence or reduced CCS.

Time to surgery is not an oncological risk factor in HCC patients undergoing liver resection.

PURPOSE: Given limitations of the health care systems in case of unforeseeable events, e.g., the COVID pandemic as well as trends in prehabilitation, time from diagnosis to surgery (time to surgery, (TTS)) has become a research issue in malignancies. Thus, we investigated whether TTS is associated with oncological outcome in HCC patients undergoing surgery. METHODS: A monocentric cohort of 217 patients undergoing liver resection for HCC between 2009 and 2021 was analyzed. Individuals were grouped according to TTS and compared regarding clinical characteristics. Overall survival (OS) and recurrence-free survival (RFS) was compared using Kaplan-Meier analysis and investigated by univariate and multivariable Cox regressions. RESULTS: TTS was not associated with OS (p=0.126) or RFS (p=0.761) of the study cohort in univariate analysis. In multivariable analysis age (p=0.028), ASA (p=0.027), INR (0.016), number of HCC nodules (p=0.026), microvascular invasion (MVI; p<0.001), and postoperative complications (p<0.001) were associated with OS and INR (p=0.005), and number of HCC nodules (p<0.001) and MVI (p<0.001) were associated with RFS. A comparative analysis of TTS subgroups was conducted (group 1, ≤30 days, n=55; group 2, 31-60 days, n=79; group 3, 61-90 days, n=45; group 4, >90 days, n=38). Here, the median OS were 62, 41, 38, and 40 months (p=0.602 log rank) and median RFS were 21, 26, 26, and 25 months (p=0.994 log rank). No statistical difference regarding oncological risk factors were observed between these groups. CONCLUSION: TTS is not associated with earlier tumor recurrence or reduced overall survival in surgically treated HCC patients.

Identification and Validation of Potentially Clinically Relevant CpG Regions within the Class 2 Tumor Suppressor Gene SFRP1 in Pancreatic Cancer.

In pancreatic cancer treatment, tumor stage-dependent chemotherapies are used to prolong overall survival. By measuring DNA promoter hypermethylation in the plasma of patients with stage IV pancreatic cancer, it was recently shown that promoter DNA methylation of the tumor suppressor gene SFRP1 has a high value for predicting failure of drug treatment with gemcitabine. In this study, we therefore aimed to identify as precisely as possible the region in the SFRP1 promoter that is frequently hypermethylated in pancreatic cancer tissue. First, we used the TCGA data set to define CpG-rich regions flanking the SFRP1 transcription start site that were significantly more methylated in pancreatic cancer compared to normal pancreatic acinar tissue. A core CpG island was identified that exhibited abundant tumor DNA methylation and anti-correlation of SFRP1 mRNA expression. To validate our in silico results, we performed bisulfide conversion followed by DNA pyrosequencing of 28 matched formalin-fixed, paraffin-embedded (FFPE) pancreatic cancer cases and six pancreatic cancer cell lines. A defined block of seven CpG sites within the core CpG island was identified, which confirmed our in silico results by showing significantly higher SFRP1 methylation in pancreatic cancer specimens than in normal pancreatic tissue. By selecting this core CpG island, we were able to determine a median overall survival benefit for the low SFRP1 methylation group compared to the high SFRP1 methylation group (702 versus 517 days, p = 0.01) in the TCGA pancreatic cancer cohort. We propose a compact pyrosequencing assay that can be used in the future to further investigate the prognostic value of SFRP1 promoter hypermethylation in predicting pancreatic cancer chemoresistance. Therefore, instead of DNA analysis from blood (liquid biopsy), DNA easily extractable from cancer tissue blocks (FFPE material) could be used.

The Role of Single-Nucleotide Polymorphisms in Cholangiocarcinoma: A Systematic Review.

Single-nucleotide polymorphisms (SNPs) play an essential role in various malignancies, but their role in cholangiocarcinoma (CCA) remains to be elucidated. Therefore, the purpose of this systematic review was to evaluate the association between SNPs and CCA, focusing on tumorigenesis and prognosis. A systematic literature search was carried out using PubMed, Embase, Web of Science and the Cochrane database for the association between SNPs and CCA, including literature published between January 2000 and April 2022. This systematic review compiles 43 SNPs in 32 genes associated with CCA risk, metastatic progression and overall prognosis based on 34 studies. Susceptibility to CCA was associated with SNPs in genes related to inflammation (PTGS2/COX2, IL6, IFNG/IFN-γ, TNF/TNF-α), DNA repair (ERCC1, MTHFR, MUTYH, XRCC1, OGG1), detoxification (NAT1, NAT2 and ABCC2), enzymes (SERPINA1, GSTO1, APOBEC3A, APOBEC3B), RNA (HOTAIR) and membrane-based proteins (EGFR, GAB1, KLRK1/NKG2D). Overall oncological prognosis was also related to SNPs in eight genes (GNB3, NFE2L2/NRF2, GALNT14, EGFR, XRCC1, EZH2, GNAS, CXCR1). Our findings indicate that multiple SNPs play different roles at various stages of CCA and might serve as biomarkers guiding treatment and allowing oncological risk assessment. Considering the differences in SNP detection methods, patient ethnicity and corresponding environmental factors, more large-scale multicentric investigations are needed to fully determine the potential of SNP analysis for CCA susceptibility prediction and prognostication.

PD-1+ T-Cells Correlate with Nerve Fiber Density as a Prognostic Biomarker in Patients with Resected Perihilar Cholangiocarcinoma.

BACKGROUND AND AIMS: Perihilar cholangiocarcinoma (pCCA) is a hepatobiliary malignancy, with a dismal prognosis. Nerve fiber density (NFD)-a novel prognostic biomarker-describes the density of small nerve fibers without cancer invasion and is categorized into high numbers and low numbers of small nerve fibers (high vs low NFD). NFD is different than perineural invasion (PNI), defined as nerve fiber trunks invaded by cancer cells. Here, we aim to explore differences in immune cell populations and survival between high and low NFD patients. APPROACH AND RESULTS: We applied multiplex immunofluorescence (mIF) on 47 pCCA patients and investigated immune cell composition in the tumor microenvironment (TME) of high and low NFD. Group comparison and oncological outcome analysis was performed. CD8+PD-1 expression was higher in the high NFD than in the low NFD group (12.24 × 10-6 vs. 1.38 × 10-6 positive cells by overall cell count, p = 0.017). High CD8+PD-1 expression was further identified as an independent predictor of overall (OS; Hazard ratio (HR) = 0.41; p = 0.031) and recurrence-free survival (RFS; HR = 0.40; p = 0.039). Correspondingly, the median OS was 83 months (95% confidence interval (CI): 18-48) in patients with high CD8+PD-1+ expression compared to 19 months (95% CI: 5-93) in patients with low CD8+PD-1+ expression (p = 0.018 log rank). Furthermore, RFS was significantly lower in patients with low CD8+PD-1+ expression (14 months (95% CI: 6-22)) compared to patients with high CD8+PD-1+ expression (83 months (95% CI: 17-149), p = 0.018 log rank). CONCLUSIONS: PD-1+ T-cells correlate with high NFD as a prognostic biomarker and predict good survival; the biological pathway needs to be investigated.

Limitations of Nerve Fiber Density as a Prognostic Marker in Predicting Oncological Outcomes in Hepatocellular Carcinoma.

It has been shown that the presence and density of nerve fibers (NFs; NFD) in the tumor microenvironment (TME) may play an important prognostic role in predicting long-term oncological outcomes in various malignancies. However, the role of NFD in the prognosis of hepatocellular carcinoma (HCC) is yet to be explored. To this end, we aimed to investigate the impact of NFs on oncological outcomes in a large European single-center cohort of HCC patients. In total, 153 HCC patients who underwent partial hepatectomy in a curative-intent setting between 2010 and 2021 at our university hospital were included in this study. Group comparisons between patients with and without NFs were conducted and the association of recurrence-free survival (RFS) and overall survival (OS) with the presence of NFs and other clinico-pathological variables were determined by univariate and multivariable Cox regression models. Patients with NFs in the TME presented with a median OS of 66 months (95% CI: 30−102) compared to 42 months (95% CI: 20−63) for patients without NFs (p = 0.804 log-rank). Further, RFS was 26 months (95% CI: 12−40) for patients with NFs compared to 18 months (95% CI: 9−27) for patients without NFs (p = 0.666 log-rank). In a subgroup analysis, patients with NFD ≤ 5 showed a median OS of 54 months (95% CI: 11−97) compared to 48 months (95% CI: 0−106) for the group of patients with NFD > 5 (p = 0.787 log-rank). Correspondingly, the RFS was 26 months (95% CI: 10−42) in patients with NFD ≤ 5 and 29 months (95% CI: 14−44) for the subcohort with NFD > 5 (p = 0.421 log-rank). Further, group comparisons showed no clinico-pathological differences between patients with NFs (n = 76) and without NFs (n = 77) and NFs were not associated with OS (p = 0.806) and RFS (p = 0.322) in our Cox regression models. In contrast to observations in various malignancies, NFs in the TME and NFD are not associated with long-term oncological outcomes in HCC patients undergoing surgery.

The role of tumor-infiltrating lymphocytes in cholangiocarcinoma.

Cholangiocarcinoma (CCA) is the second most common primary liver cancer and associated with a dismal prognosis due to the lack of an efficient systemic therapy. In contrast to other cancers, new immunotherapies have demonstrated unsatisfactory results in clinical trials, underlining the importance of a deeper understanding of the special tumor microenvironment of CCA and the role of immune cells interacting with the tumor. Tumor-infiltrating lymphocytes (TILs) are an important component of the adaptive immune system and the foundation of current immunotherapy. Therefore, the aim of this systemic review is to summarize the current literature focusing on the proportions and distribution, molecular pathogenesis, prognostic significance of TILs and their role in immunotherapy for CCA patients.In CCA, CD8+ and CD4+ T lymphocytes represent the majority of TILs and are mostly sequestered around the cancer cells. CD20+ B lymphocytes and Natural Killer (NK) cells are less frequent. In contrast, Foxp3+ cells (regulatory T cells, Tregs) are observed to infiltrate into the tumor. In the immune microenvironment of CCA, cancer cells and stromal cells such as TAMs, TANs, MSDCs and CAFs inhibit the immune protection function of TILs by secreting factors like IL-10 and TGF-ß. With respect to molecular pathogenesis, the Wnt/-catenin, TGF-signaling routes, aPKC-i/P-Sp1/Snail Signaling, B7-H1/PD-1Pathway and Fas/FasL signaling pathways are connected to the malignant potential and contributed to tumor immune evasion by increasing TIL apoptosis. Distinct subtypes of TILs show different prognostic implications for the long-term outcome in CCA. Although there are occasionally conflicting results, CD8+ and CD4+ T cells, and CD20+ B cells are positively correlated with the oncological prognosis of CCA, while a high number of Tregs is very likely associated with worse overall survival. TILs also play a major role in immunotherapy for CCA.In summary, the presence of TILs may represent an important marker for the prognosis and a potential target for novel therapy, but more clinical and translationaldata is needed to fully unravel the importance of TILs in the treatment of CCA.

The Presence of Small Nerve Fibers in the Tumor Microenvironment as Predictive Biomarker of Oncological Outcome Following Partial Hepatectomy for Intrahepatic Cholangiocarcinoma.

The oncological role of the density of nerve fibers (NFs) in the tumor microenvironment (TME) in intrahepatic cholangiocarcinoma (iCCA) remains to be determined. Therefore, data of 95 iCCA patients who underwent hepatectomy between 2010 and 2019 was analyzed regarding NFs and long-term outcome. Extensive group comparisons were carried out and the association of cancer-specific survival (CSS) and recurrence-free survival (RFS) with NFs were assessed using Cox regression models. Patients with iCCA and NFs showed a median CSS of 51 months (5-year-CSS = 47%) compared to 27 months (5-year-CSS = 21%) in patients without NFs (p = 0.043 log rank). Further, NFs (hazard ratio (HR) = 0.39, p = 0.002) and N-category (HR = 2.36, p = 0.010) were identified as independent predictors of CSS. Patients with NFs and without nodal metastases displayed a mean CSS of 89 months (5-year-CSS = 62%), while patients without NFs or with nodal metastases but not both showed a median CCS of 27 months (5-year-CSS = 25%) and patients with both positive lymph nodes and without NFs showed a median CCS of 10 months (5-year-CSS = 0%, p = 0.001 log rank). NFs in the TME are, therefore, a novel and important prognostic biomarker in iCCA patients. NFs alone and in combination with nodal status is suitable to identify iCCA patients at risk of poor oncological outcomes following curative-intent surgery.

Development and validation of deep learning classifiers to detect Epstein-Barr virus and microsatellite instability status in gastric cancer: a retrospective multicentre cohort study.

BACKGROUND: Response to immunotherapy in gastric cancer is associated with microsatellite instability (or mismatch repair deficiency) and Epstein-Barr virus (EBV) positivity. We therefore aimed to develop and validate deep learning-based classifiers to detect microsatellite instability and EBV status from routine histology slides. METHODS: In this retrospective, multicentre study, we collected tissue samples from ten cohorts of patients with gastric cancer from seven countries (South Korea, Switzerland, Japan, Italy, Germany, the UK and the USA). We trained a deep learning-based classifier to detect microsatellite instability and EBV positivity from digitised, haematoxylin and eosin stained resection slides without annotating tumour containing regions. The performance of the classifier was assessed by within-cohort cross-validation in all ten cohorts and by external validation, for which we split the cohorts into a five-cohort training dataset and a five-cohort test dataset. We measured the area under the receiver operating curve (AUROC) for detection of microsatellite instability and EBV status. Microsatellite instability and EBV status were determined to be detectable if the lower bound of the 95% CI for the AUROC was above 0·5. FINDINGS: Across the ten cohorts, our analysis included 2823 patients with known microsatellite instability status and 2685 patients with known EBV status. In the within-cohort cross-validation, the deep learning-based classifier could detect microsatellite instability status in nine of ten cohorts, with AUROCs ranging from 0·597 (95% CI 0·522-0·737) to 0·836 (0·795-0·880) and EBV status in five of eight cohorts, with AUROCs ranging from 0·819 (0·752-0·841) to 0·897 (0·513-0·966). Training a classifier on the pooled training dataset and testing it on the five remaining cohorts resulted in high classification performance with AUROCs ranging from 0·723 (95% CI 0·676-0·794) to 0·863 (0·747-0·969) for detection of microsatellite instability and from 0·672 (0·403-0·989) to 0·859 (0·823-0·919) for detection of EBV status. INTERPRETATION: Classifiers became increasingly robust when trained on pooled cohorts. After prospective validation, this deep learning-based tissue classification system could be used as an inexpensive predictive biomarker for immunotherapy in gastric cancer. FUNDING: German Cancer Aid and German Federal Ministry of Health.

Nerve Fibers in the Tumor Microenvironment as a Novel Biomarker for Oncological Outcome in Patients Undergoing Surgery for Perihilar Cholangiocarcinoma.

INTRODUCTION: Perihilar cholangiocarcinoma (pCCA) is a biliary tract cancer with a dismal prognosis, with surgery being the only chance of cure. A characteristic aggressive biological feature of pCCA is perineural growth which is defined by the invasion of cancer cells to nerves and nerve fibers. Recently, nerve fiber density (NFD) was linked to oncological outcomes in various malignancies; however, its prognostic role in pCCA remains to be elucidated. MATERIALS AND METHODS: Data of 101 pCCA patients who underwent curative-intent surgery between 2010 and 2019 were included in this study. Extensive group comparisons between patients with high and low NFD were carried out, and the association of cancer-specific survival (CSS) and recurrence-free survival with NFD and other clinicopathological characteristics was assessed using univariate and multivariable cox regression models. RESULTS: Patients with high NFD showed a median CSS of 90 months (95% CI: 48-132, 3-year CSS = 77%, 5-year CSS = 72%) compared to 33 months (95% CI: 19-47, 3-year CSS = 46%, 5-year CSS = 32%) in patients with low NFD (p = 0.006 log rank). Further, N1 category (HR = 2.84, p = 0.001) and high NFD (HR = 0.41, p = 0.024) were identified as independent predictors of CSS in multivariable analysis. Patients with high NFD and negative lymph nodes showed a median CSS of 90 months (3-year CSS = 88%, 5-year CSS = 80%), while patients with either positive lymph nodes or low NFD displayed a median CSS of 51 months (3-year CSS = 59%, 5-year CSS = 45%) and patients with both positive lymph nodes and low NFD a median CSS of 24 months (3-year CSS = 26%, 5-year CSS = 16%, p = 0.001 log rank). CONCLUSION: NFD has been identified as an important novel prognostic biomarker in pCCA patients. NFD alone and in combination with nodal status in particular allows to stratify pCCA patients based on their risk for inferior oncological outcomes after curative-intent surgery.

Bacterial bile duct colonization in perihilar cholangiocarcinoma and its clinical significance.

Abdominal infections including cholangitis represent a major problem in patients with perihilar cholangiocarcinoma (pCCA). Thus, we investigated bacterial colonization of the bile ducts and determined its impact on postoperative outcome focusing on abdominal infections. A cohort of 95 pCCA patients who underwent surgery between 2010 and 2019 with available intraoperative microbial bile cultures were analyzed regarding bile duct colonization and postoperative abdominal infection by group comparisons and logistic regressions. 84.2% (80/95) showed bacterial colonization of the bile ducts and 54.7% (52/95) developed postoperative abdominal infections. Enterococcus faecalis (38.8%, 31/80), Enterococcus faecium (32.5%, 26/80), Enterobacter cloacae (16.3%, 13/80) and Escherichia coli (11.3%, 9/80) were the most common bacteria colonizing the bile ducts and Enterococcus faecium (71.2%, 37/52), Enterococcus faecalis (30.8%, 16/52), Enterobacter cloacae (25.0%, 13/52) and Escherichia coli (19.2%, 10/52) the most common causes of postoperative abdominal infection. Further, reduced susceptibility to perioperative antibiotic prophylaxis (OR = 10.10, p = .007) was identified as independent predictor of postoperative abdominal infection. Bacterial colonization is common in pCCA patients and reduced susceptibility of the bacteria to the intraoperative antibiotic prophylaxis is an independent predictor of postoperative abdominal infections. Adapting antibiotic prophylaxis might therefore have the potential to improve surgical outcome pCCA patients.