Diagnostic rate of germline pathogenic variants in pancreatic ductal adenocarcinoma patients using whole genome sequencing.

Identification of germline pathogenic variants in cancer patients is critical for treatment planning, genetic counseling, and health policymaking. However, previous estimates of the prevalence of germline etiology of pancreatic ductal adenocarcinoma (PDAC) were biased because they were based only on sequencing data of protein-coding regions of known PDAC candidate genes. To determine the percentage of patients with PDAC carrying germline pathogenic variants, we enrolled the inpatients from the digestive health clinics, hematology and oncology clinics, and surgical clinics of a single tertiary medical center in Taiwan for whole genome sequencing (WGS) analysis of genomic DNA. The virtual gene panel of 750 genes comprised PDAC candidate genes and those listed in the COSMIC Cancer Gene Census. The genetic variant types under investigation included single nucleotide substitutions, small indels, structural variants, and mobile element insertions (MEIs). In 8 of 24 (33.3%) patients with PDAC, we identified pathogenic/likely pathogenic variants, including single nucleotide substitutions and small indels in ATM, BRCA1, BRCA2, POLQ, SPINK1 and CASP8, as well as structural variants in CDC25C and USP44. We identified additional patients carrying variants that could potentially affect splicing. This cohort study demonstrates that an extensive analysis of the abundant information yielded by the WGS approach can uncover many pathogenic variants that could be missed by traditional panel-based or whole exome sequencing-based approaches. The percentage of patients with PDAC carrying germline variants might be much higher than previously expected.

Accuracy of simultaneous measurement of serum biomarkers: Carbohydrate antigen 19-9, pancreatic elastase-1, amylase, and lipase for diagnosing pancreatic ductal adenocarcinoma.

BACKGROUND: Pancreatic cancer is difficult to diagnose early since tumor markers have low sensitivity and specificity. We simultaneously measured serum carbohydrate antigen (CA) 19-9, pancreatic elastase-1, lipase, and amylase, and evaluated the accuracy of a single marker or a combination of two, three, or four markers in the diagnosis of pancreatic ductal adenocarcinoma (PDAC). METHODS: Seventy-six patients with PDAC were included, and 75 patients with non-PDAC diseases were enrolled as the control group. Blood specimens were collected and analyzed for pancreatic elatase-1, CA19-9, amylase and lipase. Sensitivity, specificity, and accuracy for each individual marker and in combination were determined. RESULTS: In PDAC subjects, abnormal CA19-9 was seen most frequently at 80.3%, followed by pancreatic elastase-1 at 57.9%, lipase at 53.9%, and amylase at 51.3%. In non-PDAC subjects, the percentage of abnormal serum pancreatic elastase-1, CA19-9, lipase, and amylase were 50.7%, 41.3%, 40.0%, and 28.0%, respectively. The accuracy rate of amylase and CA19-9 results combined was 64.9% and was higher than the combination of other markers in the intersection set. In the union set, the group of amylase and CA19-9 combined and the group of lipase and CA19-9 combined had the highest accuracy at 66.2%. In the intersection and union set, the area under the curve of CA19-9 was the highest at 0.695. CONCLUSION: CA19-9 as a single marker is the most accurate in the clinical diagnosis of PDAC. Combination of lipase, amylase, or pancreatic elastase-1 results does not significantly increase the accuracy of PDAC diagnosis.

Risk factors related to age at diagnosis of pancreatic cancer: a retrospective cohort pilot study.

BACKGROUND: Increased pancreatic cancer incidence has been observed among younger than in older adults. This pilot study aimed to determine the feasibility of a large study that would compare the age at diagnosis of pancreatic cancer among patients with different risk factors. METHODS: We compared the age at diagnosis of pancreatic cancer between groups of pancreatic cancer patients exposed and not exposed to the identified risk factors. We estimated the age at which exposure started, average exposure quantity, and total years of exposure and investigated their relationships with age at diagnosis of pancreatic cancer. RESULTS: Sixteen out of 24 (67%) subjects carried known genetic factors and/or had smoking and/or drinking habits; however, an earlier age of pancreatic cancer diagnosis was not observed. Conversely, we found a significant correlation between the age at which alcohol consumption was started and the age at diagnosis of pancreatic cancer (r = 0.8124, P = 0.0043). CONCLUSIONS: Our pilot study suggested that a large study following this study design is feasible and that the following should be conducted in a large study: mediation analysis for disease-related factors, advanced genomic analysis for new candidate genes, and the correlation between age of first exposure to risk factors and pancreatic cancer onset.

Endoscopic ultrasound-guided fine-needle biopsy as a tool for studying the intra-tumoral microbiome in pancreatic ductal adenocarcinoma: a pilot study.

A new approach by investigating the intra-tumoral microbiome raised great interest because they may influence the host immune response and natural history of the disease. However, previous studies on the intra-tumoral microbiome of pancreatic ductal adenocarcinoma (PDAC) were mostly based on examining the formalin-fixed paraffin-embedded tumor specimens. This study aims to investigate the feasibility of using endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) as a complementary procedure of surgical biopsy to obtain adequate fresh pancreatic cancer tissue for intra-tumoral microbial research. This was a prospective pilot study performed at a single tertiary referral center. We obtained pancreatic cancer tissue by EUS-FNB and surgical biopsy, respectively. We amplified the V3-V4 hyper-variable region of bacterial 16S ribosomal ribonucleic acid (rRNA) genes, constructed a pair-end library, and performed high-throughput sequencing. From August 2020 to November 2020, nine eligible patients with PDAC were enrolled in this study. The intra-tumoral microbiome profile was successfully generated from the PDAC cancer tissue obtained by EUS-FNB as well as by surgical biopsy. There was no significant difference in intra-tumoral alpha-diversity or bacterial taxonomic composition between tissues obtained by EUS-FNB and by surgical biopsy. EUS-FNB can collect sufficient fresh cancer tissue for microbiome analyses without complication. The intra-tumoral microbiome profile in tissues obtained by EUS-FNB had similar alpha-diversity and taxonomic profiles with those obtained by surgical biopsy. It implicated, except for surgical biopsy, EUS-FNB can be another valid and valuable tool for studying intra-tumoral microbiome in patients with resectable and unresectable PDAC.

Predictors of response and survival in patients with unresectable hepatocellular carcinoma treated with nivolumab: real-world experience.

Real-world predictors of the treatment efficacy of immune checkpoint inhibitors for hepatocellular carcinoma (HCC) are unknown. This retrospective study enrolled 87 consecutive patients with unresectable HCC from May 2017 to December 2019 at two hospitals. Of the 87 patients, 7, 9, 60, and 11 patients had Barcelona Clinic Liver Cancer stages A, B, C, and D, respectively, and 45, 30, and 10 patients were Child-Pugh class A, B, and C, respectively. The median injection numbers of nivolumab and treatment duration were 6 (3-8) and 2.53 (1.47-4.23) months, respectively, and 64.4% of patients received combination therapy. Radiological imaging was not assessed for 25 patients. Objective response (OR) and disease control rates were 19.5% and 39.1%, respectively. A single tumor (odds ratio: 9.542, P = .015) and ≥20% decline in serum α-fetoprotein protein (AFP) levels within the first 3 months of treatment (defined as AFP response, odds ratio: 5.997, P = .042) were predictors of OR. Lack of macrovascular invasion, combination therapy, and AFP response were predictors of progression-free survival. A Cancer of the Liver Italian Program (CLIP) score of 0-2 (hazard ratio [HR]: 3.717, P = .004) and grade 1-2 immune-related adverse events (irAEs, HR: 2.217, P = .049) were predictors of overall survival (OS) in the entire cohort, and a CLIP score of 0-2 (HR: 3.257, P = .009) was a predictor of OS in evaluable patients. IrAEs ≥ grade 3 were noted in 14 patients, and three died as a result. Having a single tumor and AFP response were predictors of OR, and CLIP score was a predictor of OS.

Effectiveness of image-guided radiotherapy for locally advanced esophageal squamous cell carcinoma patients treated with definitive concurrent chemoradiotherapy.

BACKGROUND: Image-guided radiotherapy (IGRT) is an advanced radiotherapy technique to improve the accuracy of treatment delivery. However, a recent randomized controlled trial (RCT) for prostate cancer patients treated with radiotherapy either via IGRT or routine care (no daily IGRT) reported a statistically significant worse overall survival for those treated with IGRT. This raised the concern regarding the effectiveness of IGRT for definitive concurrent chemoradiotherapy (dCCRT) for locally advanced esophageal squamous cell carcinoma (LA-ESqCC). METHODS: Eligible LA-ESqCC patients diagnosed between 2011 and 2015 were identified via the Taiwan Cancer Registry. We estimated propensity scores to construct a 1:1 propensity-score-matched groups and balance observable potential confounders. The hazard ratio (HR) of death as well as other outcomes was compared between IGRT and non-IGRT matched groups during the entire follow-up period. The impact of additional covariables was considered in the sensitivity analysis. RESULTS: Our study population included 590 patients in the primary analysis. The HR for death when IGRT was compared with non-IGRT was 0.92 (95% confidence interval 0.77-1.10, P = 0.35). There were also no significant differences for other outcomes or sensitivity analyses. CONCLUSIONS: In this updated nonrandomized study using real world data, we found that the overall survival of LA-ESqCC patients treated with dCCRT was not statistically different between those treated with IGRT versus those without IGRT, although the hazard ratio was less than unity, ie, in favor of IGRT. The results should be interpreted with caution given the nonrandomized design and RCTs are needed to clarify our findings. KEY POINTS: Significant findings of the study: The OS of LA-ESqCC patients treated with dCCRT was not statistically different between those treated with IGRT versus those without IGRT, although the hazard ratio was less than unity, ie, in favor of IGRT. WHAT THIS STUDY ADDS: In this updated nonrandomized study using real world data with additional potential confounders, our study provided a reasonable tentative evidence of lack of RCT as suggested in the literature.