Side-by-side placement of fully covered metal stents versus conventional 7F plastic stents in malignant hilar biliary obstruction: Prospective randomized controlled trial

OBJECTIVES

We aimed to evaluate the efficacy and safety of metal stents compared with plastic stents when bilateral side-by-side stents were deployed for malignant hilar biliary obstruction (MHBO).

METHODS

Fifty patients with unresectable advanced MHBO were randomly assigned to the metal stent (MS, n = 25) or plastic stent group (PS, n = 25). Fully covered self-expandable metal stents with 6 mm diameter and plastic stents with either 7F straight or double pigtail were used for MS and PS groups, respectively. Time to recurrent biliary obstruction (TRBO) was evaluated as the primary outcome.

RESULTS

Both groups had 100% technical success rates; 88% and 76% of clinical success rates were obtained in MS and PS, respectively. Although stent migrations were more frequent in MS than PS (48% vs. 16%, P = 0.02), the mean TRBO was significantly longer in MS (190 days; 95% confidence interval [CI] 121-260 days vs. 96 days; 95% CI 50-141 days, P = 0.02). The placement of plastic stents (hazard ratio 2.42; 95% CI 1.24-4.73; P = 0.01) was the only significant risk factor associated with TRBO in multivariable analysis. The rates of adverse events were similar between the two groups (difference 0%; 95% CI -25% to 25%; P > 0.99).

CONCLUSIONS

During bilateral side-by-side deployment in MHBO, the use of metal stents appears to be preferable to plastic stents in terms of TRBO, despite a higher frequency of stent migration.

The predictive value of PD-L1 expression in response to anti-PD-1/PD-L1 therapy for biliary tract cancer: a systematic review and meta-analysis

Background

Recently, anti-programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) immunotherapy offers promising results for advanced biliary tract cancer (BTC). However, patients show highly heterogeneous responses to treatment, and predictive biomarkers are lacking. We performed a systematic review and meta-analysis to assess the potential of PD-L1 expression as a biomarker for treatment response and survival in patients with BTC undergoing anti-PD-1/PD-L1 therapy.

Methods

We conducted a comprehensive systematic literature search through June 2023, utilizing the PubMed, EMBASE, and Cochrane Library databases. The outcomes of interest included objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), and overall survival (OS) according to PD-L1 expression. Subgroup analyses and meta-regression were performed to identify possible sources of heterogeneity.

Results

A total of 30 studies was included in the final analysis. Pooled analysis showed no significant differences in ORR (odds ratio [OR], 1.56; 95% confidence intervals [CIs], 0.94-2.56) and DCR (OR, 1.84; 95% CIs, 0.88-3.82) between PD-L1 (+) and PD-L1 (-) patients. In contrast, survival analysis showed improved PFS (hazard ratio [HR], 0.54, 95% CIs, 0.41-0.71) and OS (HR, 0.58; 95% CI, 0.47-0.72) among PD-L1 (+) patients compared to PD-L1 (-) patients. Sensitivity analysis excluding retrospective studies showed no significant differences with the primary results. Furthermore, meta-regression demonstrated that drug target (PD-1 vs. PD-L1), presence of additional intervention (monotherapy vs. combination therapy), and PD-L1 cut-off level (1% vs. ≥5%) significantly affected the predictive value of PD-L1 expression.

Conclusion

PD-L1 expression might be a helpful biomarker for predicting PFS and OS in patients with BTC undergoing anti-PD-1/PD-L1 therapy. The predictive value of PD-L1 expression can be significantly influenced by diagnostic or treatment variables.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO, identifier CRD42023434114.

Removal of intrahepatic bile duct stone could reduce the risk of cholangiocarcinoma: A single-center retrospective study in South Korea

BACKGROUND

Intrahepatic duct (IHD) stones are among the most important risk factors for cholangiocarcinoma (CCC). Approximately 10% of patients with IHD stones develop CCC; however, there are limited studies regarding the effect of IHD stone removal on CCC development.

AIM

To investigate the association between IHD stone removal and CCC development.

METHODS

We retrospectively analyzed 397 patients with IHD stones at a tertiary referral center between January 2011 and December 2020.

RESULTS

CCC occurred in 36 of the 397 enrolled patients. In univariate analysis, chronic hepatitis B infection (11.1% vs 3.0%, P = 0.03), carbohydrate antigen 19-9 (CA19-9, 176.00 vs 11.96 II/mL, P = 0.010), stone located in left or both lobes (86.1% vs 70.1%, P = 0.042), focal atrophy (52.8% vs 26.9%, P = 0.001), duct stricture (47.2% vs 24.9%, P = 0.004), and removal status of IHD stone (33.3% vs 63.2%, P < 0.001) were significantly different between IHD stone patients with and without CCC. In the multivariate analysis, CA19-9 > upper normal limit, carcinoembryonic antigen > upper normal limit, stones located in the left or both lobes, focal atrophy, and complete removal of IHD stones without recurrence were independent factors influencing CCC development. However, the type of removal method was not associated with CCC risk.

CONCLUSION

Complete removal of IHD stones without recurrence could reduce CCC risk.

Survival benefit of concurrent chemoradiotherapy for advanced ampulla of Vater cancer

BACKGROUND

Currently, there is no standard adjuvant therapy for patients with resected ampulla of Vater (AoV) cancer.

AIM

To evaluate the effectiveness of adjuvant concurrent chemoradiotherapy (CCRT) in patients with advanced AoV cancer who underwent curative resection.

METHODS

This single-centered, retrospective study included 29 patients with advanced AoV cancer who underwent pancreaticoduodenectomy between 2006 and 2018. The impact of CCRT on advanced AoV cancer was analyzed.

RESULTS

The 1-, 3-, and 5-yr recurrence-free survival (RFS) rates for patients with advanced AoV cancer were 82.8%, 48.3%, and 40.8%, respectively, and the overall survival (OS) rates were 89.7%, 62.1%, and 51.7%, respectively. Lymphovascular invasion was found to be a significant risk factor for RFS and OS in patients with advanced AoV cancer in the univariate analysis, whereas T stage and lymph node metastasis were significantly associated with OS in the multivariate analysis. Compared to the patients who did not receive adjuvant CCRT, those who received adjuvant CCRT did not show statistically significant improvements in the RFS and OS, although they had a significantly lower average age and significantly higher platelet-to-lymphocyte ratio.

CONCLUSION

Adjuvant CCRT did not improve survival outcomes in patients with advanced AoV cancer. These findings contribute to existing knowledge on the effectiveness of CCRT in this patient population and provide important insights for clinical decision-making.

Clinical impact of ampulla of Vater cancer subtype classification based on immunohistochemical staining

BACKGROUND

The histological subtype is an important prognostic factor for ampulla of Vater (AoV) cancer. This study proposes a classification system for the histological subtyping of AoV cancer based on immunohistochemical (IHC) staining and its prognostic significance.

METHODS

Seventy-five AoV cancers were analyzed for cytokeratin 7 (CK7), CK20, and causal-type homeobox transcription factor 2 (CDX2) expression by IHC staining. We differentiated the subtypes (INT, intestinal; PB, pancreatobiliary; MIX, mixed; NOS, not otherwise specified) into classification I: CK7/CK20, classification II: CK7/CK20 or CDX2, classification III: CK7/CDX2 and examined their associations with clinicopathological factors.

RESULTS

Classifications I, II, and III subtypes were INT (7, 10, and 10 cases), PB (43, 37, and 38 cases), MIX (13, 19, and 18 cases), and NOS (12, 9, and 9 cases). Significant differences in disease-free survival among the subtypes were observed in classifications II and III using CDX2; the PB and NOS subtype exhibited shorter survival time compared with INT subtype. In classification III, an association was revealed between advanced T/N stage, poor differentiation, lymphovascular invasion (LVI), the PB and NOS subtypes, and recurrence risk. In classification III, the subtypes differed significantly in T/N stage and LVI. Patients with the PB subtype had advanced T and N stages and a higher incidence of LVI.

CONCLUSIONS

Classification using CDX2 revealed subtypes with distinct prognostic significance. Combining CK7 and CDX2 or adding CDX2 to CK7/CK20 is useful for distinguishing subtypes, predicting disease outcomes, and impacting the clinical management of patients with AoV cancer.

Efficacy of GV1001 with gemcitabine/capecitabine in previously untreated patients with advanced pancreatic ductal adenocarcinoma having high serum eotaxin levels (KG4/2015): an open-label, randomised, Phase 3 trial

BACKGROUND

The TeloVac study indicated GV1001 did not improve the survival of advanced pancreatic ductal adenocarcinoma (PDAC). However, the cytokine examinations suggested that high serum eotaxin levels may predict responses to GV1001. This Phase III trial assessed the efficacy of GV1001 with gemcitabine/capecitabine for eotaxin-high patients with untreated advanced PDAC.

METHODS

Patients recruited from 16 hospitals received gemcitabine (1000 mg/m2, D 1, 8, and 15)/capecitabine (830 mg/m2 BID for 21 days) per month either with (GV1001 group) or without (control group) GV1001 (0.56 mg; D 1, 3, and 5, once on week 2-4, 6, then monthly thereafter) at random in a 1:1 ratio. The primary endpoint was overall survival (OS) and secondary end points included time to progression (TTP), objective response rate, and safety.

RESULTS

Total 148 patients were randomly assigned to the GV1001 (n = 75) and control groups (n = 73). The GV1001 group showed improved median OS (11.3 vs. 7.5 months, P = 0.021) and TTP (7.3 vs. 4.5 months, P = 0.021) compared to the control group. Grade >3 adverse events were reported in 77.3% and 73.1% in the GV1001 and control groups (P = 0.562), respectively.

CONCLUSIONS

GV1001 plus gemcitabine/capecitabine improved OS and TTP compared to gemcitabine/capecitabine alone in eotaxin-high patients with advanced PDAC.

CLINICAL TRIAL REGISTRATION

NCT02854072.

Metastatic pancreatic solitary fibrous tumor: A case report

BACKGROUND

Solitary fibrous tumor (SFT) is a rare mesenchymal tumor that is most commonly found in the pleura but can also originate from non-pleural sites. Among the non-pleural localizations, the pancreas is extremely rare. In particular, metastasis to the pancreas from the central nervous system (CNS) is extremely rare, with only two cases reported so far. We report a case of recurrence in the pancreas 14 years after the initial complete surgical removal of a tumor in the CNS.

CASE SUMMARY

A 68-year-old man with a past medical history of recurrent meningeal hemangiopericytoma, currently referred to as SFT, presented to the hospital with jaundice. The patient was first diagnosed with an 8cm-sized meningeal hemangiopericytoma fourteen years ago and underwent osteoplastic craniotomy. After 16 mo, imaging showed recurrence and he underwent gamma knife radiosurgery (GKRS). 2 years later, imaging showed recurrence again leading to a second GKRS. 5 years later, recurrence was again suspected leading to a second craniotomy. Since then 3 years had passed, and imaging showed a 3.5cm-sized mass lesion on the pancreatic head with obstruction of the pancreatic and bile ducts. Endosonography with fine-needle aspiration biopsy was done preoperatively and aided in the diagnosis of SFT. The patient underwent pylorus-preserving pancreaticoduodenectomy. Pathologic findings of the resected pancreatic specimen, consistent with the previously resected brain specimen, confirmed the diagnosis of SFT.

CONCLUSION

The rarity and lack of knowledge about SFTs make suspecting and diagnosing this disease challenging. We believe that a report of metastatic pancreatic SFT from the CNS will contribute to a better understanding of this rare disease.

Clinicopathological characteristics of extrahepatic biliary neuroendocrine neoplasms in the gallbladder, extrahepatic biliary tract, and ampulla of Vater: A single-center cross-sectional study

Backgrounds/Aims

In 2019, the grading and staging system for neuroendocrine neoplasms (NENs) was significantly changed. In this study, we report the clinicopathological characteristics and surgical outcomes of patients with extrahepatic biliary NENs who underwent curative resection with or without adjuvant treatment.

Methods

We retrospectively reviewed a database of 16 patients who developed NENs, neuroendocrine carcinoma (NEC), and mixed endocrine non-endocrine neoplasms (MiNENs) after curative resection. Among them, eight patients had ampulla of Vater (AoV) tumors, and eight patients had non-AoV tumors.

Results

G1 and G2 were more frequently observed in the AoV group than in the non-AoV group (12.5% and 62.5%, respectively). In contrast, NEC and MiNEN were more common in the non-AoV group (50.0%). High Ki-67 index (> 20%) and perineural invasion (PNI) were more frequently observed in the non-AoV group. Advanced age (> 65 years), mitotic count > 20 per 2 mm2, and Ki-67 index > 20% were strongly correlated with patient survival (p = 0.018, 0.009, and 0.044, respectively). Advanced age (> 65 years) and mitotic count > 20 per 2 mm2 were significantly correlated with disease recurrence (p = 0.033 and 0.010, respectively).

Conclusions

AoV and non-AoV tumors had significant differences in the histologic grade, Ki67, and PNI. Patients with non-AoV tumors had an increased risk for survival and recurrence than those in the AoV group. For extrahepatic biliary NENs, early detection of tumors, adequate surgery, and aggressive adjuvant treatment for high-risk patients are important to achieve long-term survival and prevent disease recurrence.

Spiral-phase-objective for a compact spiral-phase-contrast microscopy

Spiral-phase-contrast imaging, which utilizes a spiral phase optical element, has proven to be effective in enhancing various aspects of imaging, such as edge contrast and shadow imaging. Typically, the implementation of spiral-phase-contrast imaging requires the formation of a Fourier plane through a 4f optical configuration in addition to an existing optical microscope. In this study, we present what we believe to be a novel single spiral-phase-objective, integrating a spiral phase plate, which can be easily and simply applied to a standard microscope, such as a conventional objective. Using a new hybrid design approach that combines ray-tracing and field-tracing simulations, we theoretically realized a well-defined and high-quality vortex beam through the spiral-phase-objective. The spiral-phase-objective was designed to have conditions that are practically manufacturable while providing predictable performance. To evaluate its capabilities, we utilized the designed spiral-phase-objective to investigate isotropic spiral phase contrast and anisotropic shadow imaging through field-tracing simulations, and explored the variation of edge contrast caused by changes in the thickness of the imaging object.

Efficacy Analysis of Suprapapillary versus Transpapillary Self-Expandable Metal Stents According to the Level of Obstruction in Malignant Extrahepatic Biliary Obstruction

Background/Aims

The use of a self-expandable metal stent (SEMS) is recommended for unresectable malignant biliary obstruction (MBO). Stent-related adverse events might differ according to the position of the stent through the ampulla of Vater (AOV). We retrospectively evaluated SEMS patency and adverse events according to the position of the SEMS.

Methods

In total, 280 patients who underwent endoscopic SEMS placement due to malignant distal biliary obstruction were analyzed retrospectively. Suprapapillary and transpapillary SEMS insertions were performed on 51 patients and 229 patients, respectively.

Results

Between the suprapapillary group (SPG) and transpapillary group (TPG), the stent patency period was not significantly different (median [95% confidence interval]: 107 days [82.3 to 131.7] vs 120 days [99.3 to 140.7], p=0.559). There was also no significant difference in the rate of adverse events. In subgroup analysis, the stent patency for an MBO located within 2 cm from the AOV was found to be significantly shorter than that for an MBO located more than 2 cm from the AOV in the SPG (64 days [0 to 160.4] vs 127 days [82.0 to 171.9], p<0.001) and TPG (87 days [52.5 to 121.5] vs 130 [97.0 to 162.9], p<0.001). Patients with an MBO located within 2 cm from the AOV in both groups had a higher percentage of duodenal invasion (SPG: 40.0% vs 4.9%, p=0.002; TPG: 28.6% vs 2.9%, p<0.001) than patients with an MBO located more than 2 cm from the AOV.

Conclusions

The SPG and TPG showed similar results in terms of stent patency and rate of adverse events. However, patients with an MBO located within 2 cm from the AOV had a higher percentage of duodenal invasion with shorter stent patency than those with an MBO located more than 2 cm from the AOV, regardless of stent position.

Postoperative delirium after cholecystectomy in older patients: A retrospective study

Backgrounds/Aims

Postoperative delirium (POD) is a common complication that increases mortality and morbidity in older patients. This study aimed to evaluate the clinical significance of post-cholecystectomy delirium in older patients.

Methods

This retrospective study included 201 patients aged > 75 years who underwent cholecystectomy for acute or chronic cholecystitis between January 2016 and December 2019. Patients were divided into the POD (n = 21) and non-POD (n = 180) groups, and their demographic features and clinical results were compared.

Results

The mean patient age was 78.88 years; the female/male ratio was 44.8%/55.2%. Laparoscopic surgery was performed in 93.5% of patients. The univariate analysis showed that lower body mass index (BMI), immobilized admission status, neuropsychiatric disease history, preoperative intervention (percutaneous drainage), high C-reactive protein, hypoalbuminemia, neutrophilia, hypo-/hyperkalemia, and longer operative time were more frequently observed in the POD group. The multivariate analysis showed that lower BMI (odds ratio [OR], 2.796; p = 0.024), neuropsychiatric disease history (OR, 3.019; p = 0.049), hyperkalemia (OR, 5.972; p = 0.007), and longer operative time (OR, 1.011; p = 0.013) were significant risk factors for POD.

Conclusions

POD was associated with inflammation degree, general condition, poor nutritional status, electrolyte imbalance, and stressful conditions. Recognizing risk factors requiring multidisciplinary team approaches is important to prevent and treat POD.

The efficacy of low-dose CT with deep learning image reconstruction in the surveillance of incidentally detected pancreatic cystic lesions

PURPOSE

To evaluate the efficacy of low-dose CT (LDCT) with deep learning image reconstruction (DLIR) for the surveillance of pancreatic cystic lesions (PCLs) compared with standard-dose CT (SDCT) with adaptive statistical iterative reconstruction (ASIR-V).

METHODS

The study enrolled 103 patients who underwent pancreatic CT for follow-up of incidentally detected PCLs. The CT protocol included LDCT in the pancreatic phase with 40% ASIR-V, DLIR at medium (DLIR-M) and high levels (DLIR-H), and SDCT in the portal-venous phase with 40% ASIR-V. The overall image quality and conspicuity of PCLs were qualitatively assessed using five-point scales by two radiologists. The size of PCLs, presence of thickened/enhancing walls, enhancing mural nodules, and main pancreatic duct dilatation were reviewed. CT noise and cyst-to-pancreas contrast-to-noise ratio (CNR) were measured. Qualitative and quantitative parameters were analyzed using the chi-squared test, one-way ANOVA, and t-test. Additionally, interobserver agreement was analyzed using the kappa and weighted-kappa statistics.

RESULTS

The volume CT dose-indexes in LDCT and SDCT were 3.0 ± 0.6 mGy and 8.4 ± 2.9 mGy, respectively. LDCT with DLIR-H showed the highest overall image quality, the lowest noise, and the highest CNR. The PCL conspicuity in LDCT with either DLIR-M or DLIR-H was not significantly different from that in SDCT with ASIR-V. Other findings depicting PCLs also revealed no significant differences between LDCT with DLIR and SDCT with ASIR-V. Moreover, the results revealed good or excellent interobserver agreement.

CONCLUSION

LDCT with DLIR has a comparable performance with SDCT for the follow-up of incidentally detected PCLs.

Patient-derived Organoid Model for Predicting the Chemoresponse in Patients With Colorectal Cancer

BACKGROUND/AIM

Cancer mortality has decreased due to the contribution of extensive research on cancer treatment, including chemotherapy, radiation, and immunotherapy. However, histopathologically similar tumors originating from the same organ are treated with identical or similar chemotherapeutic regimens regardless of patient characteristics or cancer subtypes. The aim of this study was to evaluate the utility of organoids in predicting responses to chemotherapeutic agents.

PATIENTS AND METHODS

This study retrospectively reviewed patient-derived organoids (PDOs) from 10 colorectal cancer patients to compare chemotherapy responses. Drug sensitivities for 5-fluorouracil (5-FU), cisplatin, oxaliplatin, and irinotecan were compared using GI50 (concentration that inhibits cancer cell growth by 50%).

RESULTS

When organoids were treated with 5-FU, GI50 was the lowest compared to the other three chemotherapeutic agents (cisplatin, oxaliplatin, and irinotecan). The responsiveness to chemotherapeutic agents differed depending on specific patient characteristics including age, tumor location, stage, and gross type. The response of the patients' organoids to chemotherapeutic agents was consistent with the response to chemotherapy actually performed in those patients with cancer recurrence after surgery.

CONCLUSION

PDOs may be useful as a preclinical model in predicting chemotherapy responses in cancer patients.

Zanidatamab for HER2-amplified, unresectable, locally advanced or metastatic biliary tract cancer (HERIZON-BTC-01): a multicentre, single-arm, phase 2b study

BACKGROUND

HER2 is overexpressed or amplified in a subset of biliary tract cancer. Zanidatamab, a bispecific antibody targeting two distinct HER2 epitopes, exhibited tolerability and preliminary anti-tumour activity in HER2-expressing or HER2 (also known as ERBB2)-amplified treatment-refractory biliary tract cancer.

METHODS

HERIZON-BTC-01 is a global, multicentre, single-arm, phase 2b trial of zanidatamab in patients with HER2-amplified, unresectable, locally advanced, or metastatic biliary tract cancer with disease progression on previous gemcitabine-based therapy, recruited at 32 clinical trial sites in nine countries in North America, South America, Asia, and Europe. Eligible patients were aged 18 years or older with HER2-amplified biliary tract cancer confirmed by in-situ hybridisation per central testing, at least one measurable target lesion per Response Evaluation Criteria in Solid Tumours (version 1.1), and an Eastern Cooperative Oncology Group performance status of 0 or 1. Patients were assigned into cohorts based on HER2 immunohistochemistry (IHC) score: cohort 1 (IHC 2+ or 3+; HER2-positive) and cohort 2 (IHC 0 or 1+). Patients received zanidatamab 20 mg/kg intravenously every 2 weeks. The primary endpoint was confirmed objective response rate in cohort 1 as assessed by independent central review. Anti-tumour activity and safety were assessed in all participants who received any dose of zanidatamab. This trial is registered with ClinicalTrials.gov, NCT04466891, is ongoing, and is closed to recruitment.

FINDINGS

Between Sept 15, 2020, and March 16, 2022, 87 patients were enrolled in HERIZON-BTC-01: 80 in cohort 1 (45 [56%] were female and 35 [44%] were male; 52 [65%] were Asian; median age was 64 years [IQR 58-70]) and seven in cohort 2 (five [71%] were male and two [29%] were female; five [71%] were Asian; median age was 62 years [IQR 58-77]). At the time of the data cutoff (Oct 10, 2022), 18 (21%) patients (17 in cohort 1 and one in cohort 2) were continuing to receive zanidatamab; 69 (79%) discontinued treatment (radiographic progression in 64 [74%] patients). The median duration of follow-up was 12·4 months (IQR 9·4-17·2). Confirmed objective responses by independent central review were observed in 33 patients in cohort 1 (41·3% [95% CI 30·4-52·8]). 16 (18%) patients had grade 3 treatment-related adverse events; the most common were diarrhoea (four [5%] patients) and decreased ejection fraction (three [3%] patients). There were no grade 4 treatment-related adverse events and no treatment-related deaths.

INTERPRETATION

Zanidatamab demonstrated meaningful clinical benefit with a manageable safety profile in patients with treatment-refractory, HER2-positive biliary tract cancer. These results support the potential of zanidatamab as a future treatment option in HER2-positive biliary tract cancer.

FUNDING

Zymeworks, Jazz, and BeiGene.

Risk Factors for Early- and Late-Onset Cholecystitis after Y-Configured Metal Stent Placement in Patients with Malignant Hilar Biliary Obstruction: A Single-Center Study

This study evaluated the prevalence and risk factors of early- (within 7 days of placement) and late-onset (after 7 days of placement) cholecystitis after Y-configured metal stent placement. Between June 2005 and August 2020, 109 patients who had been treated with Y-configured metal stents for malignant hilar obstruction were enrolled in the study. We retrospectively analyzed the potential risk factors for post-stent cholecystitis. The presence of diabetes (p = 0.042), the length of the common part of the Y-stent (p = 0.017), filling of the gallbladder with contrast medium during the procedure (p = 0.040), and tumor invasion of the cystic duct accompanied by filling the gallbladder with contrast medium during metal stent placement (p = 0.001) were identified as important risk factors. In cases of late-onset cholecystitis, stent obstruction (p = 0.004) and repeated endoscopic procedures due to stent malfunction (p = 0.024) were significant risk factors. In the multivariate logistic regression analysis, significant risk factors were the length of the common part of the Y-stent (p = 0.032) in early-onset cholecystitis and stent obstruction (p = 0.007) in late-onset cholecystitis. This study demonstrated that early-onset cholecystitis may occur in patients according to the length of the common portion of the Y-stent. In contrast, late-onset cholecystitis may occur in patients with stent obstruction.

Clinical significance of C-reactive protein-to-prealbumin ratio in predicting early recurrence in resectable pancreatic cancer

PURPOSE

Resectable pancreatic ductal adenocarcinoma (PDAC) has a high risk of recurrence after curative resection; despite this, the preoperative risk factors for predicting early recurrence remain unclear. This study therefore aimed to identify preoperative inflammation and nutrition factors associated with early recurrence of resectable PDAC.

METHODS

From March 2021 to November 2021, a total of 20 patients who underwent curative resection for PDAC were enrolled in this study. We evaluated the risk factors for early recurrence within 1 year by univariate and multivariate analyses using Cox hazard proportional regression. The cutoff values for predicting recurrence were examined using receiver operating characteristic (ROC) curves.

RESULTS

In our univariate and multivariate analyses, C-reactive protein (CRP), CRP-albumin ratio, and CRP-prealbumin ratio, as well as sex and age, were significant independent prognostic factors for early recurrence in PDAC. However, known inflammatory factors (neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios), nutritional factors (albumin, prealbumin, ferritin, vitamin D), and inflammatory-nutritional factors (Glasgow Prognostic Score, modified Glasgow Prognostic Score, albumin-bilirubin) showed no association with early recurrence. In addition, using cutoff values by ROC curve analysis, a high preoperative CRP level of >5 mg/L, as well as high CRP-to-albumin (>5.3) and CRP-to-prealbumin (>1.3) ratios showed no prognostic value.

CONCLUSION

Our results showed that inflammatory and perioperative nutritional factors, especially CRP-to-prealbumin ratio, have significant associations with early recurrence after curative resection in resectable PDAC. Therefore, for such patients, a cautious approach is needed when inflammation and poor nutritional status are present.

Comparison of Two Types of Guidewires for Malignant Hilar Biliary Obstruction by Endoscopic Retrograde Cholangiopancreatography: A Randomized Controlled Trial

Background: There is insufficient information regarding the optimal guidewire for managing malignant hilar biliary obstruction (MHBO). Therefore, a newly designed 0.025-inch guidewire was compared with the conventional 0.035-inch guidewire for selective cannulation of both intrahepatic ducts (IHDs) in patients with MHBO. Methods: Patients were randomly enrolled into the curved type newly designed 0.025-inch guidewire group (0.025 group) or the curved type conventional 0.035-inch guidewire group (0.035 group). The primary outcome was the selective cannulation rate of IHD. If the assigned guidewire failed to pass the stricture within 5 min, the crossover guidewire was selected. If the crossover guidewire failed to cross the stricture within the next 5 min, it was judged as a failed selective cannulation of both IHDs. Results: A total of 90 patients were enrolled (0.025 group, n = 47; 0.035 group, n = 43). There was no significant difference in baseline characteristics between the groups regarding sex, age, BMI, obstruction level, and clinical presentation. Four patients (8.5%) in the 0.025 group the cannulation of the IHD failed and the conventional 0.035-inch guidewire was substituted in a second attempt; the 0.035-inch guidewire failed to cross the stricture in all four patients. In the 0.035 group, eleven patients (25.6%) failed to achieve selective cannulation of IHD, and the 0.025-inch guidewire was substituted; the newly designed 0.025-inch guidewire crossed the stricture in ten of these (10/11, 90.9%). The selective cannulation rate of IHD was significantly higher in the 0.025 group (95.1% vs. 85.5%, p = 0.043). Conclusions: The 0.025 group exhibited a higher success rate for selective cannulation of both IHDs in MHBO than did the 0.035 group.

Efficacy of a Newly Developed Guidewire for Selective Biliary Cannulation: A Multicenter Randomized Controlled Trial

BACKGROUND AND AIMS

Various guidewires are used for biliary cannulation, and each one has its own characteristics affecting its effectiveness. This study aimed to measure the basic properties and evaluate the effectiveness of a newly developed 0.025-inch guidewire for selective biliary cannulation.

METHODS

A total of 190 patients at five referral hospitals were randomly allocated to undergo selective biliary cannulation using the newly developed guidewire (NGW group, n = 95) or a conventional guidewire (CGW group, n = 95). The primary outcome was the selective biliary cannulation rate in naïve papillae. The secondary outcome was to measure the NGW basic properties, compare them with those of the CGW, and analyze the importance of basic property differences.

RESULTS

There were no significant differences between the groups in the baseline characteristics. The primary outcome (75.8% vs. 84.2%, p = 0.102) and adverse event rate (6.3% vs. 4.2%, p = 0.374) were similar in both groups. However, compared with the CGW group, the NGW group showed a higher number of ampulla contacts (2.58 vs. 2.02, p = 0.011) and longer cannulation time (216.5 vs. 135.1 s, p = 0.016). Furthermore, the NGW group had higher maximum friction (34.6 ± 1.34 vs. 30.2 ± 4.09), lower stiffness, and better elastic resiliency. In the multivariate analysis, a curved-tip GW (OR = 0.26, 95% CI 0.11-0.62, p = 0.002) and normal papillary shape (OR = 0.39, 95% CI 0.17-0.86, p = 0.021) were contributing factors for successful selective biliary cannulation.

CONCLUSIONS

The NGW group had high friction and low stiffness, characteristics affecting biliary cannulation. Clinically, the NGW group had similar success and adverse event rates as the CGW, but they showed a higher number of ampulla contacts and longer cannulation time.

Spectrally encoded dual-mode interferometry with orthogonal scanning

Spectrally encoded confocal microscopy (SECM) is a high-speed reflectance confocal microscopy technique. Here, we present a method to integrate optical coherence tomography (OCT) and SECM for complementary imaging by adding orthogonal scanning to the SECM configuration. The co-registration of SECM and OCT is automatic, as all system components are shared in the same order, eliminating the need for additional optical alignment. The proposed multimode imaging system is compact and cost-effective while providing the benefits of imaging aiming and guidance. Furthermore, speckle noise can be suppressed by averaging the speckles generated by shifting the spectral-encoded field in the direction of dispersion. Using a near infrared (NIR) card and a biological sample, we demonstrated the capability of the proposed system by showing SECM imaging at depths of interest guided by the OCT in real time and speckle noise reduction. Interfaced multimodal imaging of SECM and OCT was implemented at a speed of approximately 7 frames/s using fast-switching technology and GPU processing.

Label-free photothermal optical coherence microscopy to locate desired regions of interest in multiphoton imaging of volumetric specimens

Biochip-based research is currently evolving into a three-dimensional and large-scale basis similar to the in vivo microenvironment. For the long-term live and high-resolution imaging in these specimens, nonlinear microscopy capable of label-free and multiscale imaging is becoming increasingly important. Combination with non-destructive contrast imaging will be useful for effectively locating regions of interest (ROI) in large specimens and consequently minimizing photodamage. In this study, a label-free photothermal optical coherence microscopy (OCM) serves as a new approach to locate the desired ROI within biological samples which are under investigation by multiphoton microscopy (MPM). The weak photothermal perturbation in sample by the MPM laser with reduced power was detected at the endogenous photothermal particles within the ROI using the highly sensitive phase-differentiated photothermal (PD-PT) OCM. By monitoring the temporal change of the photothermal response signal of the PD-PT OCM, the hotspot generated within the sample focused by the MPM laser was located on the ROI. Combined with automated sample movement in the x-y axis, the focal plane of MPM could be effectively navigated to the desired portion of a volumetric sample for high-resolution targeted MPM imaging. We demonstrated the feasibility of the proposed method in second harmonic generation microscopy using two phantom samples and a biological sample, a fixed insect on microscope slide, with dimensions of 4 mm wide, 4 mm long, and 1 mm thick.

HER2 status based on breast cancer guidelines as a useful prognostic marker of T2 gallbladder cancer

INTRODUCTION

T2 gallbladder cancer (GBC) is the only stage showing a survival benefit after complete surgical resection, but recurrence rates remain high. Although human epidermal growth factor receptor 2 (HER2) has emerged as a therapeutic target, its role in T2 GBC remains unclear. This study investigated the status and prognostic impact of HER2 expression on T2 GBC.

MATERIALS AND METHODS

HER2 expression and amplification were detected by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH), respectively, in 90 patients with T2 GBC who underwent radical cholecystectomy. We evaluated HER2 status according to the breast and gastric cancer guidelines and analyzed the effect of relevant prognostic factors on survival.

RESULTS

HER2 positive status was observed in 11.11% (10/90) and 8.89% (8/90) of cases based on gastric and breast cancer guidelines, respectively. Poor differentiation and a higher level of perineural invasion were independent prognostic factors of disease-free survival (DFS). Old age, male sex, presence of lymph node metastasis, poor differentiation, high levels of perineural invasion, and HER2 positivity based on breast cancer guidelines were identified as independent prognostic factors of overall survival (OS). Patients with HER2-positive T2 GBC according to breast cancer guidelines had worse OS.

CONCLUSIONS

HER2 positivity based on breast- but not gastric-cancer guidelines was associated with poorer survival. These results provide a criterion for the evaluation of HER2 and a rationale for therapeutic strategies targeting HER2 in T2 GBC.

Clinical impact of serum prealbumin in pancreaticobiliary disease

Purpose

Although there are many studies on prealbumin in individual diseases such as malignant or inflammatory diseases, there are few comparative studies. This study aimed to compare the clinical differences between prealbumin levels in cholecystitis and pancreaticobiliary malignancies and investigate the clinical impact of low prealbumin levels in pancreaticobiliary malignancies.

Methods

From June 2021 to September 2021, 61 patients who had undergone surgery for various pancreaticobiliary diseases were enrolled in this study, and their clinicopathological data were retrospectively analyzed.

Results

Many elderly patients with malignant diseases had poor American Society of Anesthesiologists (ASA) scores, significantly lower albumin and prealbumin levels, and higher systemic immune inflammation indices. The low prealbumin group was older; had poorer ASA scores; and had significantly lower body mass index and hemoglobin and albumin levels and higher systemic immune inflammation indices than the normal prealbumin group. In malignant diseases, the low prealbumin group had significantly lower body mass index and hemoglobin levels and a tendency toward more advanced disease (lymph node and distant metastasis).

Conclusion

Preoperative low prealbumin levels had an area under the receiver operator characteristic curve of 0.69, suggesting that it may be useful for predicting pancreaticobiliary malignancies. Prealbumin levels were lower in malignant diseases, possibly related to poor nutritional status and systemic immune inflammation. Low prealbumin levels may predict the risk of more advanced disease.

Endoscopist-Driven Sedation Practices in South Korea: Re-evaluation Considering the Nationwide Survey in 2019

Background/Aims

This study aimed to determine changes in endoscopist-driven sedation practices 5 years after the first nationwide survey in 2014 by the Korean Society of Gastrointestinal Endoscopy (KSGE).

Methods

A 59-item survey covering current practices was electronically mailed to all members of the KSGE in 2019.

Results

In total, 955 (12.8%) out of 7,486 questionnaires were returned. A total of 738 (77.7%) out of 955 respondents attended dedicated sedation education programs. The American Society of Anesthesiologists class was recorded by 464 (51.2%) out of 907 respondents. The recording rate was higher in respondents who completed sedation education (p=0.014) and worked in general or tertiary hospitals (p<0.001). Compared to that reported in the previous survey, the reported use of propofol was higher in 2019. The respondents had higher satisfaction scores for propofol-based sedation compared with midazolam monotherapy (p<0.001). The rates of oxygen supplementation (p<0.001) and oxygen saturation level monitoring (p<0.001) during sedative endoscopy were higher in 2019 than in the previous survey. A total of 876 (98.4%) out of 890 respondents reported a separate recovery bay, and 615 (70.5%) out of 872 respondents reported that personnel were assigned solely to the recovery bay.

Conclusions

Endoscopist-driven sedation and monitoring practices in 2019 were significantly different than those in 2014. The respondents favored propofol-based sedation and utilized oxygen supplementation and monitoring of O₂ saturation more frequently in 2019 than in 2014.

Wavelength-tunable spiral-phase-contrast imaging

Wavelength-tunable spiral-phase-contrast (SPC) imaging was experimentally accomplished in the visible wavelengths spanning a broad bandwidth of ∼200 nm based on a single off-axis spiral phase mirror (OSPM). By the rotation of an OSPM, which was designed with an integer orbital angular momentum (OAM) of l = 1 at a wavelength of 561 nm and incidence angle of 45°, high-quality SPC imaging was obtained at different wavelengths. For the comparison with wavelength-tunable SPC imaging using an OSPM, SPC imaging using a spiral phase plate (manufactured to generate an OAM of l = 1 at 561 nm) was performed at three wavelengths (473, 561, and 660 nm), resulting in clear differences. Theoretically, based on field tracing simulations, high-quality wavelength-tunable SPC imaging could be demonstrated in a very broad bandwidth of ∼400 nm, which is beyond the bandwidth of ∼200 nm obtained experimentally. This technique contribute to developing high-performance wavelength-tunable SPC imaging by simply integrating an OSPM into the current optical imaging technologies.

Diagnostic performance of magnetic resonance image for malignant intraductal papillary mucinous neoplasms: the importance of size of enhancing mural nodule within cyst

PURPOSE

To investigate the clinical significance of enhancing mural nodules ≥ 5 mm by comparing the diagnostic performance of high-risk stigmata for diagnosing the malignant IPMN between the international consensus guideline (ICG) 2012 and 2017 in pancreatic magnetic resonance image (MRI).

MATERIALS AND METHODS

In this retrospective study, we reviewed preoperative pancreatic MRI with surgically confirmed IPMNs between May 2009 and April 2021. High-risk stigmata, defined by ICG 2012 and ICG 2017, associated with malignant IPMN were evaluated using logistic regression analysis. We calculated and compared the sensitivity and specificity of ICG 2012 and ICG 2017 for diagnosing malignant IPMNs. Receiver-operating characteristic (ROC) curves were used to compare ICG 2012 to ICG 2017.

RESULTS

A total of 73 patients (43 men and 30 women; mean age, 69 years; standard deviation, 8 years) with 34 malignant IPMNs and 39 benign IPMNs were included. Among high-risk stigmata, enhancing mural nodule ≥ 5 mm, and MPD diameter ≥ 10 mm were the significant predictor of malignant IPMN, in multivariate logistic regression (P < 0.001 for all). For the diagnosis of malignant IPMN, the specificity of ICG 2017 for enhancing mural nodules ≥ 5 mm as the high-risk stigmata was significantly higher than that of ICG 2012 (87.2% vs. 64.1%, P = 0.008). However, there was no significant difference in sensitivity between the two guidelines (94.1% vs. 97.1%, P = 1.0). The comparison of the ROC curves showed that the diagnostic performance of ICG 2017 for malignant IPMNs (AUC, 0.91) significantly improved when compared to that of ICG 2012 (AUC, 0.81) (P = 0.01).

CONCLUSION

When applying enhancing mural nodule ≥ 5 mm as a high-risk stigmata, ICG 2017 provided a significantly higher specificity than ICG 2012 without a reduction in sensitivity.

Comparison of the Malignant Predictors in Intrahepatic and Extrahepatic Intraductal Papillary Neoplasm of the Bile Duct

Background: Intraductal papillary neoplasm of the bile duct (IPNB) is a precancerous lesion of cholangiocarcinoma, for which surgical resection is the most effective treatment. We evaluated the predictors of malignancy in IPNB according to anatomical location and the prognosis without surgery. Methods: A total of 196 IPNB patients who underwent pathologic confirmation by surgical resection or endoscopic retrograde cholangiography or percutaneous transhepatic cholangioscopic biopsy were included. Clinicopathological findings of IPNB with invasive carcinoma or mucosal dysplasia were analyzed according to anatomical location. Results: Of the 116 patients with intrahepatic IPNB (I-IPNB) and 80 patients with extrahepatic IPNB (E-IPNB), 62 (53.4%) and 61 (76.3%) were diagnosed with invasive carcinoma, respectively. Multivariate analysis revealed that mural nodule > 12 mm (p = 0.043) in I-IPNB and enhancement of mural nodule (p = 0.044) in E-IPNB were predictive factors for malignancy. For pathologic discrepancy before and after surgery, IPNB has a 71.2% sensitivity and 82.3% specificity. In the non-surgical IPNB group, composed of nine I-IPNB and seven E-IPNB patients, 43.7% progressed to IPNB with invasive carcinoma within 876 days. Conclusions: E-IPNB has a higher rate of malignancy than I-IPNB. The predictive factor for malignancy is mural nodule > 12 mm in I-IPNB and mural nodule enhancement in E-IPNB.

Relationship between high bile juice amylase levels and chronic bacterial infections in patients with gallbladder cancer

Purpose

Pancreatic enzyme reflux into the biliary tract is associated with chronic inflammation and increased cellular proliferation in the biliary epithelium, leading to biliary carcinoma. We evaluated the relationship between high bile juice amylase levels and biliary microflora in patients with malignant gallbladder lesions.

Methods

In this retrospective study, 25 gallbladder specimens were obtained from patients with gallbladder cancer to evaluate amylase levels and perform bacterial culture. The samples were divided into high and low amylase groups and culture-positive and negative groups for analysis. Bile juice amylase 3 times higher than the normal serum amylase level (36–128 IU/L) was considered high.

Results

The number of positive cultures was higher in the high amylase group than in the low amylase group, but the difference was insignificant. There were no differences in other clinicopathological factors. Sixteen patients showed positive culture results; Escherichia coli and Klebsiella spp. were the most common gram-negative bacteria, whereas Enterococcus and Streptococcus spp. were the most common gram-positive bacteria. Age and bile juice amylase levels were significantly higher in the culture-positive group than in the culture-negative group. The incidence of bacterial resistance to cephalosporins was 6.25%–35.29%, and this incidence was particularly high for lower-generation cephalosporins.

Conclusion

Bacteria in gallbladder were identified more frequently when the amylase level was high. High amylase levels in the gallbladder can be associated with caused chronic bacterial infections with occult pancreaticobiliary reflux, potentially triggering gallbladder cancer.

Efficacy and safety of temperature-controlled intraductal radiofrequency ablation in advanced malignant hilar biliary obstruction: A pilot multicenter randomized comparative trial

PURPOSE

We aimed to evaluate the efficacy and safety of temperature-controlled intraductal radiofrequency ablation (ID-RFA) for advanced malignant hilar biliary obstruction (MHBO).

METHODS

Patients were randomly assigned to RFA group (ID-RFA and bilateral plastic stent [PS]) or non-RFA group (bilateral PS) at a 1:1 ratio. Exchange to self-expanding metal stent (SEMS) was performed after 3 months or when premature PS occlusion occurred. Total event-free stent patency, overall survival (OS), and adverse events (AEs) were analyzed.

RESULTS

A total of 30 patients from three hospitals were enrolled. Stent patency and OS did not differ between the two groups (178 days vs 122 days, P = .154; 230 days vs 144 days, P = .643; respectively). In patients with each stricture length ≥11 mm on both sides, stent patency was longer in the RFA group than in the non-RFA group (175 days vs 121 days, P = .028). More patients received elective exchange to SEMS without PS occlusion in the RFA group than in the non-RFA group (69.2% vs 23.1%, P = .018). AE rates did not differ between the two groups.

CONCLUSIONS

Temperature-controlled ID-RFA for advanced MHBO was safe and feasible. It could prevent premature PS occlusion within 3 months.

Central Sarcopenia, Frailty and Comorbidity as Predictor of Surgical Outcome in Elderly Patients with Degenerative Spine Disease

Objective

People are living longer and the elderly population continues to increase. The incidence of degenerative spinal diseases (DSDs) in the elderly population is quite high. Therefore, we are facing more cases of DSD and offering more surgical solutions in geriatric patients. Understanding the significance and association of frailty and central sarcopenia as risk factors for spinal surgery in elderly patients will be helpful in improving surgical outcomes. We conducted a retrospective cohort analysis of prospectively collected data to assess the impact of preoperative central sarcopenia, frailty, and comorbidity on surgical outcome in elderly patients with DSD.

Methods

We conducted a retrospective analysis of patients who underwent elective spinal surgery performed from January 1, 2019 to September 30, 2020 at our hospital. We included patients aged 65 and over who underwent surgery on the thoracic or lumbar spine and were diagnosed as DSD. Central sarcopenia was measured by the 50th percentile of psoas : L4 vertebral index (PLVI) using the cross-sectional area of the psoas muscle. We used the Korean version of the fatigue, resistance, ambulation, illnesses, and loss of weight (K-FRAIL) scale to measure frailty. Comorbidity was confirmed and scored using the Charlson Comorbidity Index (CCI). As a tool for measuring surgical outcome, we used the Clavien-Dindo (CD) classification for postoperative complications and the length of stay (LOS).

Results

This study included 85 patients (35 males and 50 females). The mean age was 74.05±6.47 years. Using the K-FRAIL scale, four patients were scored as robust, 44 patients were pre-frail and 37 patients were frail. The mean PLVI was 0.61±0.19. According to the CD classification, 50 patients were classified as grade 1, 19 as grade 2, and four as grade 4. The mean LOS was 12.35±8.17 days. Multivariate stepwise regression analysis showed that postoperative complication was significantly associated with surgical invasiveness and K-FRAIL scale. LOS was significantly associated with surgical invasiveness and CCI. K-FRAIL scale showed a significant correlation with CCI and PLVI.

Conclusion

The present study demonstrates that frailty, comorbidity, and surgical invasiveness are important risk factors for postoperative complications and LOS in elderly patients with DSD. Preoperative recognition of these factors may be useful for perioperative optimization, risk stratification, and patient counseling.

Clinical utility of methionyl-tRNA synthetase 1 immunostaining in cytologic brushings of indeterminate biliary strictures: a multicenter prospective study

BACKGROUND AND AIMS

Endobiliary brushings are routinely used in the diagnosis, treatment, and prognostication of biliary strictures. However, standard Papanicolaou (Pap) staining has a low sensitivity in this setting, and the accuracy of brush cytology has not been established for indeterminate strictures. We therefore evaluated the diagnostic merit of methionyl-transfer RNA synthetase 1 (MARS1) immunofluorescence (IF) staining in such cytologic specimens.

METHODS

During ERCP, endobiliary brushings were obtained from patients with extrahepatic biliary strictures prospectively enrolled at 6 tertiary hospitals. Using liquid-based cytologic preparations of these samples, we performed Pap and MARS1 IF staining.

RESULTS

In total, 240 patients were eligible; of these, we compared the Pap and MARS1 IF staining results of 218 (malignant, 157; benign, 61). By conventional Pap staining, the diagnoses were distributed as follows: malignant, 55; suspicious of malignancy, 60; atypical, 45; negative for malignancy, 58. MARS1 IF staining was strongly positive in malignant biliary stricture but not so in specimens negative for malignancy. The diagnostic parameters (sensitivity, specificity, positive predictive value, negative predictive value, and accuracy) of the MARS1 IF (93.6%, 96.7%, 98.7%, 85.5%, and 94.5%, respectively) and conventional Pap (73.2%, 100%, 100%, 59.2%, and 80.7%, respectively) staining methods differed significantly (P < .0001).

CONCLUSIONS

The high sensitivity and accuracy of MARS1 IF staining enabled the detection of malignancy in patients with biliary strictures. Further prospective studies are needed to validate our findings. (Clinical trial registration number: NCT03708445.).

Generation of wavelength-tunable optical vortices using an off-axis spiral phase mirror: publisher's note

This publisher's note contains corrections to Opt. Lett.46, 4216 (2021)OPLEDP0146-959210.1364/OL.432413.

Vimentin-Positive Circulating Tumor Cells as Diagnostic and Prognostic Biomarkers in Patients with Biliary Tract Cancer

Biliary tract cancer (BTC) has poor prognosis; thus, early diagnosis is important to decrease mortality. Although vimentin-positive circulating tumor cells (V-CTCs) are a good candidate for diagnostic and prognostic biomarkers, studies on the topic are limited. We aimed to evaluate the diagnostic efficacy of V-CTCs between BTC and benign biliary disease (BBD) and determine the prognostic value of V-CTCs in BTC patients. We recruited 69 participants who had BTCs and BBDs from a single tertiary referral center. We analyzed CTCs and V-CTCs in peripheral blood using the CD-PRIME^TM system. Seven patients were excluded due to a technical failure of CTC detection. CTCs were detected in all 62 patients. CTC count > 40/mL blood (55.8% vs. 20%, p = 0.039), V-CTC count > 15/mL blood (57.7% vs. 10%, p = 0.005), and V-CTC/CTC ratio > 40% (48.1% vs. 10%, p = 0.025) were significantly different between BTCs and BBDs. Two or more of these three parameters (61.5% vs. 10%, p = 0.002) increased the accuracy. A combination of CTC markers with CA19-9 and biopsy increased the accuracy (90.4% vs. 10%, p = 0.000). V-CTC > 50/mL blood was a significant factor affecting survival (140 (66.6–213.3) vs. 253 (163.9–342.1) days, p = 0.008). V-CTC could be a potential biomarker for early diagnosis and predicting prognosis in patients with BTC.

Generation of wavelength-tunable optical vortices using an off-axis spiral phase mirror

Wavelength-tunable optical vortices with a topological charge equal to l=1 of orbital angular momentum (OAM) were experimentally realized using a single off-axis spiral phase mirror (OSPM) with lasers of various visible-light wavelengths. Using an OSPM designed for 561 nm and an incidence angle of 45°, circular doughnut-shaped l=1 optical vortices were obtained at 561, 473, and 660 nm by rotating the OSPM to modify the laser incidence angle. Wavelength-tunable l=1 optical vortices were obtained at the respective incidence angles of 45°, 53.4°, and 33.7°, because the effective geometrical thickness of the OSPM, which determines the order of OAM, was identical at each wavelength. This flexible OSPM which operates over a wide wavelength range will provide continuously wavelength-tunable optical vortices for applications in the fields of advanced optics and photonics in which optical vortices with wide wavelength tunability are in demand.

Quantitative Photothermal Characterization with Bioprinted 3D Complex Tissue Constructs for Early-Stage Breast Cancer Therapy Using Gold Nanorods

Plasmonic photothermal therapy (PPTT) using gold nanoparticles (AuNPs) has shown great potential for use in selective tumor treatment, because the AuNPs can generate destructive heat preferentially upon irradiation. However, PPTT using AuNPs has not been added to practice, owing to insufficient heating methods and tissue temperature measurement techniques, leading to unreliable and inaccurate treatments. Because the photothermal properties of AuNPs vary with laser power, particle optical density, and tissue depth, the accurate prediction of heat generation is indispensable for clinical treatment. In this report, bioprinted 3D complex tissue constructs comprising processed gel obtained from porcine skin and human decellularized adipose tissue are presented for characterization of the photothermal properties of gold nanorods (AuNRs) having an aspect ratio of 3.7 irradiated by a near-infrared laser. Moreover, an analytical function is suggested for achieving PPTT that can cause thermal damage selectively on early-stage human breast cancer by regulating the heat generation of the AuNRs in the tissue.

Primary needle-knife fistulotomy for preventing post-endoscopic retrograde cholangiopancreatography pancreatitis: Importance of the endoscopist’s expertise level

BACKGROUND

Needle-knife fistulotomy (NKF) is used as a rescue technique for difficult cannulation. However, the data are limited regarding the use of NKF for primary biliary cannulation, especially when performed by beginners.

AIM

To assess the effectiveness and safety of primary NKF for biliary cannulation, and the role of the endoscopist’s expertise level (beginner vs expert).

METHODS

We retrospectively evaluated the records of 542 patients with naïve prominent bulging papilla and no history of pancreatitis, who underwent bile duct cannulation at a tertiary referral center. The patients were categorized according to the endoscopist’s expertise level and the technique used for bile duct cannulation. We assessed the rates of successful cannulation and adverse events.

RESULTS

The baseline characteristics did not differ between the experienced and less-experienced endoscopists. The incidence rate of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) was significantly affected by the endoscopist’s expertise level in patients who received conventional cannulation with sphincterotomy (8.9% vs 3.4% for beginner vs expert, P = 0.039), but not in those who received NKF. In the multivariable analysis, a lower expertise level of the biliary endoscopist (P = 0.037) and longer total procedure time (P = 0.026) were significant risk factor of PEP in patients who received conventional cannulation with sphincterotomy but only total procedure time (P = 0.004) was significant risk factor of PEP in those who received NKF.

CONCLUSION

Primary NKF was effective and safe in patients with prominent and bulging ampulla, even when performed by less-experienced endoscopist. We need to confirm which level of endoscopist’s experience is needed for primary NKF through prospective randomized study.

KG 4/2015: A randomized, controlled, multicenter, open-label phase III clinical trial of GV1001 with gemcitabine/capecitabine in previous untreated, eotaxin-high patients with advanced pancreatic ductal adenocarcinoma

4020

Background: In the TeloVac study, GV1001 with Gemcitabine/capecitabine (G/C) did not show increased overall survival (OS) than G/C in patients (pts) with advanced pancreatic ductal adenocarcinoma (PDA). But cytokine examination suggested high serum eotaxin level may predict improved survivals in pts received GV1001 with G/C. This phase III trial was designed to assess the efficacy of GV1001 with G/C for previous untreated eotaxin-high Korean pts with advanced PDA. Methods: Eligible pts with histologically proven locally advanced and metastatic PDA (except peritoneal carcinomatosis), age > 18 years, and ECOG PS 0–2 were recruited. Pts were randomly assigned (1:1) to receive either G/C or G/C with GV1001 (G/C/GV). All pts receiving G/C/GV were with high serum eotaxin level (≥81.02 ng/mL), and the pts receiving G/C were randomly assigned again (1:1) to eotaxin-high and eotaxin-low pts. Study was designed according to Korean MFDS guidance for approval of clinical trial. G/C treatment included G (1000 mg/m2, 30 min IVF, D 1, 8, & 15) and C (830 mg/m2 BID for 21 days per month (m). G/C/GV treatment included an intradermal injection of GM-CSF (75 μg) and GV1001 (0.56 mg; D 1, 3, & 5, once on week 2–4, & 6, then monthly thereafter) from the start of G/C. The primary endpoint was OS. The secondary endpoints included time to progression (TTP), objective response rate, and safety. Survival data was analyzed using the copula graphic estimate method under dependent censoring. The response was independently assessed per RECIST v1.1. Under the one-sided significance level of 2.5% and to achieve the power of 80% of the statistical significance with the median OS difference from 7.9 to 14.9 m (HR = 0.53), 85 events and 118 registrations needed. Considering 20% drop-outs, 148 registrations were required. Results: Between Nov 2015 and Apr 2020, of 511 pts screened in 16 centers, eotaxin-high pts were identified as 34.7% (174 / 502 pts). 148 pts randomly assigned to G/C/GV (n = 75; all eotaxine-high) and G/C (n = 73; 37 eotaxine-high, 36 eotaxine-low). Median OS was significantly improved in the G/C/GV group with 11.3m [95% CI 8.6-14.0] than G/C group with 7.5 m [95% CI 5.1-10.0] (p = 0.021). Also, median TTP was significantly improved in the G/C/GV group (7.3 m [95% CI 5.0-9.7]) than in the G/C group (4.5 m [95% CI 3.2-5.8], p = 0.021). In other secondary endpoints, no statistical significance was confirmed between the two groups. Grade 3-4 treatment-emergent adverse events were reported in 49 pts (73.13%) vs. 58 pts (77.33%) in the G/C and G/C/GV group, without significant differences (p = 0.562). Conclusions: G/C/GV treatments significantly extend OS and TTP in advanced PDA than G/C, and specific safety-related issues had not been found. GV1001 should be considered as one of the options in PDA pts with high serum eotaxin levels. Clinical trial information: NCT02854072.

Real-Life Effectiveness and Safety of Glecaprevir/Pibrentasvir for Korean Patients with Chronic Hepatitis C at a Single Institution

Background/Aims

Glecaprevir/pibrentasvir (G/P) is a combination of direct-acting antiviral agents that is an approved treatment for chronic infections by all six hepatitis C virus (HCV) genotypes. However, there are limited data on the effect of G/P in Korean patients in actual real-world settings. We evaluated the real-life effectiveness and safety of G/P at a single institution in Korea.

Methods

This retrospective, observational, cohort study used sustained virologic response at 12 weeks after treatment completion (SVR12) as the primary effectiveness endpoint. Safety and tolerability were also determined.

Results

We examined 267 individuals who received G/P for chronic HCV infections. There were 148 females (55.4%), and the overall median age was 63.0 years (range, 25 to 87 years). Eighty-three patients (31.1%) had HCV genotype-1 and 182 (68.2%) had HCV-2. A total of 212 patients (79.4%) were HCV treatment-naïve, 200 (74.9%) received the 8-week treatment, 13 (4.9%) had received prior treatment for hepatocellular carcinoma, 37 (13.7%) had chronic kidney disease stage 3 or higher, and 10 (3.7%) were receiving dialysis. Intention to treat (ITT) analysis indicated that 256 (95.9%) achieved SVR12. A modified ITT analysis indicated that SVR12 was 97.7% (256/262). Six patients failed therapy because of posttreatment relapse. SVR12 was significantly lower in those who received prior sofosbuvir treatment (p=0.002) and those with detectable HCV RNA at week 4 (p=0.027). Seventy patients (26.2%) experienced one or more adverse events, and most of them were mild.

Conclusions

These real-life data indicated that G/P treatment was highly effective and well tolerated, regardless of viral genotype or patient comorbidities. (Gut Liver 2021;15-450)

The predictors of sustained virological response with sofosbuvir and ribavirin in patients with chronic hepatitis C genotype 2

BACKGROUND/AIMS

Real-world, clinical practice data are lacking about sofosbuvir/ ribavirin (SOF/RBV) treatment of Korean patients with hepatitis C virus genotype 2 (HCV GT2) infection. This study investigated the efficacy and safety of SOF/RBV in Korean patients with HCV GT2 infection and clinical factors predicting sustained virological response 12 weeks (SVR12) after the end of SOF/RBV treatment.

METHODS

A total of 181 patients with HCV GT2 with/without cirrhosis were treated with SOF/RBV for 16/12 weeks. Rapid virological response (RVR) was defined as non-detectable HCV RNA at 4 weeks.

RESULTS

The RVR rate was 80.7% (146/181), the end of treatment response rate was 97.8% (177/181) and the SVR12 rate was 92.8% (168/181). Of eight patients with relapse, four did not achieve RVR. Three patients had a history of hepatocellular carcinoma (HCC). Multivariable analysis showed that RVR (p = 0.015) and no previous history of HCC (p = 0.007) were associated with SVR12. Factors significantly contributing to RVR included cirrhosis, creatinine concentration, and pre-treatment HCV RNA level. SVR12 rate was significantly higher in RVR (+) than RVR (-) patients (95.2% vs. 82.9%, p = 0.011) and also significantly higher in patients without than with a history of HCC (94.1% vs. 72.7%, p = 0.008). During treatment, 80/181 patients (44.2%) experienced mild to moderate adverse events, with 32 (17.7%) requiring RBV dose reductions due to anemia.

CONCLUSION

SOF/RBV treatment was effective and tolerable in HCV GT2 patients. RVR and no previous history of HCC were positive predictors of SVR12.

Validation of functional liver imaging scores (FLIS) derived from gadoxetic acid-enhanced MRI in patients with chronic liver disease and liver cirrhosis: the relationship between Child-Pugh score and FLIS

OBJECTIVES

To validate the functional liver imaging score (FLIS) for prediction of hepatic function in gadoxetic acid-enhanced MRI.

METHODS

We retrospectively identified 134 patients (88 men, 46 women; mean age, 58.8 years) between January 2015 and December 2018 with the following inclusion criteria: patients diagnosed with liver cirrhosis or chronic liver disease (CLD) who underwent gadoxetic acid-enhanced MRI. Three parameters on hepatobiliary phase images were evaluated for FLIS: liver parenchymal enhancement, biliary excretion, and signal intensity of the portal vein. Patients were classified as CLD (n = 11), Child-Pugh (CP) class A (n = 87), CP B (n = 22), or CP C (n = 14). We assessed the correlation between CP score and both FLIS and its components using Spearman rank correlation. Receiver operating characteristic (ROC) curve analysis was performed to demonstrate the cutoff value of FLIS for differentiating between CP classes. The associations between patient characteristics, serum markers, FLIS, and hepatic decompensation were evaluated with Cox proportional hazard models.

RESULTS

FLIS and three FLIS parameters showed strong to very strong correlation with CP score (r = -0.60 to 0.82). ROC curve analysis showed that FLIS ≥ 5 was the optimal cutoff for prediction of CP class A or CLD (sensitivity, 83.7%; specificity, 94.4%; area under the curve [AUC], 0.93). FLIS < 5 was independently associated with the development of first hepatic decompensation in patients with CP A (HR, 50.0; 95% confidence interval, 6.2, 400.4).

CONCLUSION

FLIS showed a strong correlation with hepatic function and can stratify the CP class. In addition, FLIS can help prediction for the development of first decompensation.

KEY POINTS

• Functional liver imaging scores (FLIS) and its three parameters, derived from hepatobiliary phase image, have strong to very strong correlations with Child-Pugh (CP) scores. • FLIS can stratify patients with chronic liver disease or liver cirrhosis according to CP classification. • Low FLIS is an independent predictor for first hepatic decompensation in patients with CP class A.

Artificial intelligence-assisted analysis of endoscopic retrograde cholangiopancreatography image for identifying ampulla and difficulty of selective cannulation

The advancement of artificial intelligence (AI) has facilitated its application in medical fields. However, there has been little research for AI-assisted endoscopy, despite the clinical significance of the efficiency and safety of cannulation in the endoscopic retrograde cholangiopancreatography (ERCP). In this study, we aim to assist endoscopists performing ERCP through automatic detection of the ampulla and the identification of cannulation difficulty. We developed a novel AI-assisted system based on convolutional neural networks that predict the location of the ampulla and the difficulty of cannulation to the ampulla. ERCP data of 531 and 451 patients were utilized in the evaluation of our model for each task. Our model detected the ampulla with mean intersection-over-union 64.1%, precision 76.2%, recall 78.4%, and centroid distance 0.021. In classifying the cannulation difficulty, it achieved the recall of 71.9% for the class of easy cases and that of 61.1% for that of difficult cases. Remarkably, our model accurately detected AOV with varying morphological shape, size, and texture on par with the level of a human expert and showed promising results for recognizing cannulation difficulty. It demonstrated its potential to improve the quality of ERCP by assisting endoscopists.

First-line chemotherapy in very elderly patients with metastatic pancreatic cancer: Gemcitabine monotherapy vs combination chemotherapy

BACKGROUND

Combination chemotherapy (gemcitabine plus nab-paclitaxel and FOLFIRINOX) is widely used as the standard first-line treatment for pancreatic cancer. Considering the severe toxicities of combination chemotherapy, gemcitabine monotherapy (G mono) could be used as a first-line treatment in very elderly patients or those with a low Eastern Cooperative Oncology Group status. However, reports on the efficacy of G mono in patients older than 75 years are limited.

AIM

To evaluate the efficacy of G mono and combination chemotherapy by comparing their clinical outcomes in very elderly patients with pancreatic cancer.

METHODS

We retrospectively analyzed 104 older patients with pancreatic cancer who underwent chemotherapy with G mono (n = 45) or combination therapy (n = 59) as a first-line treatment between 2011 and 2019. All patients were histologically diagnosed with ductal adenocarcinoma. Primary outcomes were progression-free survival and overall survival. We also analyzed subgroups according to age [65-74 years (elderly) and ≥ 75 years (very elderly)]. Propensity score matching was performed to compare the outcomes between the two chemotherapy groups.

RESULTS

The baseline characteristics were significantly different between the two chemotherapy groups, especially regarding age, ratio of multiple metastases, tumor burden, and Eastern Cooperative Oncology Group performance status. After propensity score matching, the baseline characteristics were not significantly different between the chemotherapy groups in elderly and very elderly patients. In the elderly patients, the median progression-free survival (62 d vs 206 d, P = 0.000) and overall survival (102 d vs 302 d, P = 0.000) were longer in the combination chemotherapy group. However, in the very elderly patients, the median progression-free survival (147 d and 174 d, respectively, P = 0.796) and overall survival (227 d and 211 d, respectively, P = 0.739) were comparable between the G mono and combination chemotherapy groups. Adverse events occurred more frequently in the combination chemotherapy group than in the G mono group, especially thromboembolism (G mono vs nab-paclitaxel vs FOLFIRINOX; 8.9% vs 5.9% vs 28%, P = 0.041), neutropenia (40.0% vs 76.5% vs 84.0%, P = 0.000), and neuropathy (0% vs 61.8% vs 28.0%, P = 0.006).

CONCLUSION

In elderly patients, combination therapy is more effective than G mono. However, G mono is superior for the management of metastatic pancreatic cancer in very elderly patients.

Comparison of gemcitabine plus nab-paclitaxel and FOLFIRINOX in metastatic pancreatic cancer

BACKGROUND

Gemcitabine plus nab-paclitaxel (GA) and modified FOLFIRINOX (FFX) have been widely used as standard first-line treatment in pancreatic cancer. However, it is unclear which regimen is more efficacious.

AIM

To evaluate a retrospective analysis comparing the efficacy and safety of FFX and GA as first-line chemotherapeutic regimens in patients with metastatic pancreatic cancer.

METHODS

We retrospectively analyzed and compared outcomes in 101 patients who presented with pancreatic cancer and were treated with either GA (n = 54) or FFX (n = 47). Moreover, we performed subgroup analysis based on the neutrophil/lymphocyte ratio (NLR) and Eastern Cooperative Oncology Group (ECOG) performance status.

RESULTS

There were no significant differences between two groups in baseline characteristics, except for the ECOG performance status. The median progression-free survival (PFS) (6.43 mo vs 4.90 mo, P = 0.058) was comparable between two groups; however, median overall survival (OS) (10.17 mo vs 6.93 mo, P = 0.008) was longer in patients who received GA regimen. In patients with ECOG 0 (PFS: 8.93 mo vs 5.43 mo, P = 0.002; OS: 16.10 mo vs 6.97 mo, P = 0.000) and those with NLR < 3 (PFS: 8.10 mo vs 6.57 mo, P = 0.008; OS: 12.87 mo vs 9.93 mo, P = 0.002), GA regimen showed higher efficacy.

CONCLUSION

GA regimen may be recommended to the patients with NLR < 3 or ECOG 0 status although GA and FFX showed comparable efficacy outcomes in patients with metastatic pancreatic cancer.

Usefulness of intraductal RFA in patients with malignant biliary obstruction

BACKGROUND/AIMS

Intraductal radiofrequency ablation (ID-RFA) is a novel therapy for unresectable malignant biliary obstructions. ID-RFA for perihilar lesions is associated with a high risk of adverse events. We aimed to evaluate the feasibility and efficacy of temperature-controlled ID-RFA for perihilar malignant biliary obstruction.

METHODS

Sixteen patients with pathologically proven perihilar cholangiocarcinoma were prospectively enrolled to evaluate the feasibility of hilar ID-RFA. Clinical efficacy and outcomes were subsequently evaluated in a multicenter retrospective cohort.

RESULTS

Nine of the 16 patients in the prospective cohort had Bismuth type IV and 7 had type IIIA perihilar cholangiocarcinoma. The median length of stricture was 34.5 mm. The median number of ID-RFA sessions was three, and all sessions were technically and functionally successful without severe adverse events. Clinical outcomes were assessed using a multicenter hilar ID-RFA cohort of 21 patients; the median stent patency and overall survival were 90 days (range: 35-483 days) and 147 days (range: 92-487 days), respectively. An approximate 16-month patency of the bile duct was maintained in one patient who had an intraductal growth pattern. In a comparison of the self-expandable metallic stent (SEMS) and plastic stent (PS) after hilar ID-RFA, no differences in stent patency (89 vs 90.5 days, respectively; P = .912) and adverse events (20.0% vs 10%, respectively; P = .739) were observed.

CONCLUSIONS

ID-RFA at 7 W for 120 seconds is safe and feasible in patients with advanced perihilar cholangiocarcinoma. After ID-RFA, SEMS and PS placement showed comparable patency and survival rates.

TRIAL REGISTRATION NUMBER

KCT0003223.

Ultralow Water Permeation Barrier Films of Triad a-SiNx:H/n-SiOxNy/h-SiOx Structure for Organic Light-Emitting Diodes

Organic electronic devices such as organic light-emitting diodes (OLEDs), quantum dot LEDs, and organic photovoltaics are promising technologies for future electronics. However, achieving long-term stability of organic-based optoelectronic devices has been regarded as a crucial problem to be solved. In this work, a simple and reproducible fabrication method for ultralow water permeation barrier films having a triple-layered (triad) hydrogenated silicon nitride (a-SiN_x:H)/nanosilicon oxynitride (n-SiO_xN_y)/hybrid silicon oxide (h-SiO_x) multistructure is presented. Two triad (a-SiN_x:H/n-SiO_xN_y/h-SiO_x)_n=2 multistructure barrier films are deposited on both sides of a poly(ethylene terephthalate) substrate using a combination of low-pressure plasma-enhanced chemical vapor deposition and dip coating. The deposited films show a high average transmittance (400-700 nm) of 84% and an ultralow water vapor transmission rate of 2 × 10^-6 g/m²/day. In the electroluminescence characteristics of OLEDs encapsulated with two triad barrier films, the operational lifetime (T₅₀) of OLEDs is 1584 h, which is almost similar to that (1416 h) of OLEDs encapsulated with a glass lid.