The Expression of Programmed Death-Ligand 1 on Immune Cells Is Related to a Better Prognosis in Biliary Tract Cancer

Background/Aims@#Programmed death-ligand 1 (PD-L1) expression in tumor cells is associated with a poor biliary tract cancer (BTC) prognosis; tumor-infiltrating immune cells in the tumor microenvironment are associated with a better prognosis. The effect of PD-L1 expression on immune cells on survival is unclear. We investigated the relationship between PD-L1 expression in immune cells and BTC prognosis. @*Methods@#PD-L1 expression was evaluated using an anti-PD-L1 22C3 mouse monoclonal primary antibody, and its relationships with clinical characteristics and prognosis were analyzed using the Cox proportional hazard model to investigate the prognostic performance of PD-L1 in BTC. @*Results@#Among 144 analyzed cases, patients with positive PD-L1 expression in tumor cells and negative PD-L1 expression in immune cells showed poorer overall survival rates than those exhibiting other expressions (tumor cells: hazard ratio [HR]=1.023, p<0.001; immune cells: HR=0.983, p=0.021). PD-L1 expression in tumor cells was an independent predictor of poor overall survival (HR=1.024, p<0.001). In contrast, PD-L1 expression in immune cells was a predictive marker of good prognosis (HR=0.983, p=0.018). @*Conclusions@#PD-L1 expression in immune cells may be used as an independent factor to evaluate the prognosis of patients with BTC.

Machine-Learning Model for the Prediction of Hypoxaemia during Endoscopic Retrograde Cholangiopancreatography under Monitored Anaesthesia Care

Purpose@#Hypoxaemia is a significant adverse event during endoscopic retrograde cholangiopancreatography (ERCP) under monitored anaesthesia care (MAC); however, no model has been developed to predict hypoxaemia. We aimed to develop and compare logistic regression (LR) and machine learning (ML) models to predict hypoxaemia during ERCP under MAC. @*Materials and Methods@#We collected patient data from our institutional ERCP database. The study population was randomly divided into training and test sets (7:3). Models were fit to training data and evaluated on unseen test data. The training set was further split into k-fold (k=5) for tuning hyperparameters, such as feature selection and early stopping. Models were trained over k loops; the i-th fold was set aside as a validation set in the i-th loop. Model performance was measured using area under the curve (AUC). @*Results@#We identified 6114 cases of ERCP under MAC, with a total hypoxaemia rate of 5.9%. The LR model was established by combining eight variables and had a test AUC of 0.693. The ML and LR models were evaluated on 30 independent data splits. The average test AUC for LR was 0.7230, which improved to 0.7336 by adding eight more variables with an l 1 regularisation-based selection technique and ensembling the LRs and gradient boosting algorithm (GBM). The high-risk group was discriminated using the GBM ensemble model, with a sensitivity and specificity of 63.6% and 72.2%, respectively. @*Conclusion@#We established GBM ensemble model and LR model for risk prediction, which demonstrated good potential for preventing hypoxaemia during ERCP under MAC.

Comparison of Clinical Performance and Safety between Domestic New Pull-type Triple-lumen Sphincterotome and Conventional Sphincterotome: A Prospective Multicenter Trial / 대한소화기학회지

Background/Aims@#Sphincterotomes are essential for endoscopic sphincterotomy (EST) and can also be used for cannulation in ERCP.A domestic new pull-type sphincterotome (Optimos™, Taewoong, Goyang, Korea) provides acceptable technical feasibility and safety, but there are no comparison results. Thus, this study compared the clinical performance and safety of Optimos™ sphincterotome to a conventional sphincterotome (CleverCut3™, Olympus, Tokyo, Japan) in patients who underwent ERCP. @*Methods@#From April 2021 to July 2021, a randomized prospective comparative study was conducted on 104 consecutive patients who underwent ERCP in three medical centers. The primary endpoint was the clinical performance and safety of sphincterotomes during ERCP. @*Results@#One hundred and four patients were assigned randomly to the Optimos™ group (n=51) or CleverCut3™ group (n=53). All demographic characteristics did not differ between the groups except the BMI. The technical success rate for cannulation, performance of EST, and total procedure time were similar in the two groups. The adverse events did not differ, even though two cases of post-ERCP pancreatitis occurred in CleverCut3™. On the other hand, in questionnaire analysis, CleverCut™ showed a better user’s convenience (median [interquartile range] 4.0 [3.0-4.0] vs. 3.0 [3.0-4.0], p=0.013) and manipulability (median [interquartile range], 4.0 [3.0-4.0] vs. 3.0 [3.0-4.0], p=0.039) than Optimos™, even though the other profiles did not reveal any differences. @*Conclusions@#New domestic pull-type sphincterotome can offer comparable clinical performance and safety profiles to conventional sphincterotome, but it needs refinements to increase the user’s convenience and manipulability. Further improvement and innovation will be required to advance domestic medical devices.

Response to Neoadjuvant Therapy and Prognosis in Patients with Resectable Pancreatic Cancer: A Propensity Score Matching Analysis

Background/Aims@#Controversy regarding the effectiveness of neoadjuvant therapy for resectable pancreatic ductal adenocarcinoma (PDAC) still exists. Here, we aimed to identify the potential benefits of neoadjuvant therapy followed by surgery for resectable PDAC. @*Methods@#We reviewed radiologically resectable PDAC patients who received resection with curative intent at a tertiary hospital in South Korea between January 2012 and August 2019. A total of 202 patients underwent curative resection for resectable PDAC: 167 underwent surgical resection first during this period, and 35 received neoadjuvant chemotherapy/chemoradiation therapy followed by surgery. Resectable PDAC patients were subdivided, and 1:3 propensity score matching (PSM) was performed to reduce selection bias. @*Results@#Compared with the group that received surgery first, the group that received neoadjuvant treatment followed by surgery had significantly smaller tumors (22.0 mm vs 27.0 mm, p=0.004), a smaller proportion of patients with postoperative pathologic T stage (p=0.026), a smaller proportion of patients with lymphovascular invasion (20.0% vs 40.7%, p=0.022), and a larger proportion of patients with negative resection margins (74.3% vs 51.5%, p=0.049). After PSM, the group that received neoadjuvant therapy had a significantly longer progression-free survival than those in the group that underwent surgery first (29.6 months vs 15.1 months, p=0.002). Overall survival was not significantly different between the two groups after PSM analysis. @*Conclusions@#We observed significantly better surgical outcomes and progression-free survival with the addition of neoadjuvant therapy to the management of resectable PDAC. However, despite PSM, there was still selection bias due to the use of different regimens between the groups receiving surgery first and neoadjuvant therapy. Large homogeneous samples are needed in the future prospective studies.

Updates of Chemotherapy and Radiotherapy for Pancreatic Cancer / 대한췌담도학회지

Pancreatic cancer is still one of the most aggressive malignancy, showing 10% of 5-year survival. Among the several reasons of the grave prognosis, the poor response to chemotherapeutic agents and the absence of effective tool for early detection are the most important. Regarding treatments, surgical resection is still positioned as the only one for expecting the cure of pancreatic cancer. However, the rate of recurrence after surgery is still high as more than 50%. And the portion of patients who are diagnosed at the resectable stage is still less than 15% of all cases. So, chemotherapy and radiotherapy are the main players for combating with pancreatic cancer. After the introduction of outcomes of FOLFIRINOX, and gemcitabineabpaclitaxel for metastatic pancreatic cancer, two-digit overall survival can be expected. And, neoadjuvant treatments including concurrent chemoradiation therapy for borderline resectable pancreatic cancer and/or resectable pancreatic cancer are reported as superior to upfront surgery. More recently, several target agents including polyadenosine diphosphate-ribose polymerase inhibitors and immunologic drugs are under evaluation for pancreatic cancer. So, herein, current status of chemotherapy and radiation therapy for pancreatic cancer will be addressed.

Analysis of Clinical Predictive Factors Affecting the Outcome of Second-Line Chemotherapy for Gemcitabine-Refractory Advanced Pancreatic Cancer

Background/Aims@#The benefit of second-line chemotherapy (SL) after failed first-line chemotherapy (FL) in patients with advanced pancreatic cancer has not yet been established. We evaluated the clinical characteristics affecting the benefits of SL compared to best supportive care (BSC), identified the prognostic factors, and ultimately devised a model of clinical parameters to assist in making decision between SL and BSC after the failure of gemcitabine-based FL. @*Methods@#The records of patients who received gemcitabine-based FL for advanced pancreatic cancer at Yonsei University Hospital between January 2010 and December 2015 were retrospectively reviewed. Significant clinical parameters were assessed for their potential as predictive factors. @*Results@#SL patients received a longer duration of FL compared with BSC patients with median duration being 16.0 weeks (range, 8.0 to 26.0 weeks) and 8.0 weeks (range, 4.0 to 16.0 weeks), respectively (p<0.001). When the SL group was stratified by their modified overall survival (mOS) (longer and shorter than 6 months), we found significant differences for several clinical factors, namely, metastasis to the peritoneum (p<0.001), number of metastases (p<0.001), thrombotic events (p=0.003), and level of carbohydrate antigen 19-9 (CA19-9; p=0.011). In multivariate analysis, more than one site of metastasis, occurrence of thrombotic event during FL, and a CA19-9 level above 90 U/mL were significant independent prognostic factors for mOS in the SL group (p<0.05). When an attempt was made to devise a prognostic nomogram, Harrell’s C-index of the final prognosis prediction model was 0.62. @*Conclusions@#SL may be beneficial for patients without peritoneal metastasis or thrombotic events who have a single metastasis and a level of CA19-9 less than 90 U/mL. This prognostic nomogram can be used to predict mOS before the administration of SL after the failure of gemcitabine-based FL.

Bleeding Complications and Clinical Safety of Endoscopic Retrograde Cholangiopancreatography in Patients with Liver Cirrhosis

PURPOSE: Patients with liver cirrhosis are considered to be at risk for additional adverse events during endoscopic retrograde cholangiopancreatography (ERCP). The present study was designed as a propensity-score matched analysis to investigate whether cirrhotic liver increases the risk of bleeding complications in patients undergoing ERCP. MATERIALS AND METHODS: In total, 8554 patients who underwent ERCP from January 2005 to December 2015 were retrospectively analyzed. To adjust for the imbalance between patients with and those without liver cirrhosis, 1:3 propensity score matching was performed according to age and sex. RESULTS: Liver cirrhosis was identified in 264 (3.1%) patients. After propensity score matching, a total of 768 patients were included in each of the cirrhotic (n=192) and non-cirrhotic groups (n=576). Post-procedure bleeding (10.9% vs. 4.7%, p=0.003) was more frequently observed in patients with liver cirrhosis than in those without. In multivariate analyses, liver cirrhosis was identified as an independent risk factor associated with post-ERCP bleeding (p=0.003) after further adjustment for prothrombin time, antiplatelet/coagulant, duration of ERCP, and stent insertion. Child-Pugh (CP) class C was found to be associated with an increased incidence of post-ERCP bleeding in patients with cirrhosis (odds ratio 6.144, 95% confidence interval 1.320–28.606; p=0.021). CONCLUSION: The incidence of post-ERCP bleeding in patients with liver cirrhosis was higher than that in patients without liver cirrhosis. In particular, CP class C cirrhosis was significantly associated with post-ERCP bleeding.

A Case of 47-Years-Old Female with Obstructive Jaundice and Weight Loss / 대한소화기암학회지

Serine protease inhibitor Kazal-type 1 (SPINK1) is a gene expressed from pancreatic acinar cell which its mutation is known to be associated with chronic pancreatitis (CP) and pancreatic cancer. We report a case of a 47-years-old female with nausea and weight loss with yellow discoloration of skin. Initial imaging and endoscopic study led us to an impression of chronic pancreatitis with pancreatic cancer with common bile-duct dilation. Biopsy result was confirmed with pancreatic adenocarcinoma and additional imaging revealed lymph node and bone metastasis. Our genetic analysis revealed 194+2T>C mutation of SPINK1. Biliary obstruction was successfully decompressed by stent insertion and underwent chemotherapy and radiotherapy. Although there is accumulating evidence of association between SPINK1 mutation and CP, the relationship between SPINK1 mutation and pancreatic cancer in CP patient is an emerging concept. Genetic analysis should be considered in patients with young age especially when diagnosed with both CP and pancreatic cancer.

Irreversible Electroporation in Patients with Pancreatic Cancer :Angel and Devil / 대한소화기암학회지

Pancreatic cancer has a very poor prognosis. Complete surgical resection remains the only current curative treatment. Locally advanced pancreatic cancer (LAPC) is considered as unresectable because of involvement of celiac and/or mesenteric vessels. The treatment of LAPC is a challenge. Current guidelines suggest systemic therapy. However, the majority of patients will never experience conversion to surgical resection. Thus, in these patients, ablation is an alternative therapy for local control, which causes local destruction while ideally avoiding injury to surrounding healthy tissue. Irreversible electroporation (IRE) is an energy delivery system, effective in ablating tumors by inducing irreversible membrane destruction of cells. IRE demonstrated to be safe in previous studies. However, it is not free from complications, even serious. Here, we reported two cases of the IRE in LAPC patients.

Clinical Outcomes of Bilateral Stent-in-Stent Placement Using Self-Expandable Metallic Stent for High-Grade Malignant Hilar Biliary Obstruction

PURPOSE: Endoscopic bile duct decompression using bilateral self-expandable metallic stents (SEMSs) deployed via a stent-in-stent (SIS) method is considered a preferred procedure for malignant hilar biliary obstruction (MHBO). However, occlusion thereof occurs frequently. Here, we investigated stent patency duration and risk factors related to stent obstruction with bilateral SIS placement for MHBO at two large centers. MATERIALS AND METHODS: The present study reviewed data on patients with MHBO who underwent endoscopic biliary drainage using the SIS method. Clinical outcomes, including stent patency duration and patient overall survival, were analyzed. Factors associated with stent patency were evaluated using Cox proportional hazards models. RESULTS: Seventy patients with MHBO underwent endoscopic biliary drainage using the SIS method. Median age was 68 years old, and median follow-up duration was 140 days (interquartile range, 57–329). The proportion of high-grade MHBOs (Bismuth type IV) was 57.1%. Median stent patency duration with the SIS method was 108 days according to Kaplan-Meier curves. Median patient survival analyzed by the Kaplan-Meier method was 181 days. Multivariate analysis indicated that higher baseline bilirubin (> 6.1 mg/dL) as an independent risk factor related to stent patency (p < 0.05). CONCLUSION: In endoscopic biliary decompression using SEMS placed with the SIS method, obstructive jaundice was a risk factor for stent patency. The SIS method for high-grade MHBO showed short stent patency.

Clinical Value of Contrast-Enhanced Harmonic Endoscopic Ultrasonography in the Differential Diagnosis of Pancreatic and Gallbladder Masses

BACKGROUND/AIMS: Recent studies have revealed that contrast-enhanced harmonic endoscopic ultrasonography (CEH-EUS) is beneficial in the differential diagnosis of malignant neoplasms of the pancreas and gallbladder from benign masses, in terms of the evaluation of microvasculature and real-time perfusion. In this study, we aimed to prove the clinical value of CEH-EUS in the differential diagnosis of pancreatic and gallbladder masses by direct comparison with that of conventional EUS. METHODS: We reviewed the sonographic images and medical information of 471 patients who underwent conventional EUS and CEH-EUS for the diagnosis of pancreatic and gallbladder masses at a single medical center (Severance Hospital, Seoul, Korea) between March 2010 and March 2016. RESULTS: The enhancement pattern of CEH-EUS of the pancreatic solid masses showed higher sensitivity and specificity in differentiating pancreatic adenocarcinoma and neuroendocrine tumors (82.0% and 87.9% for pancreatic adenocarcinoma and 81.1% and 90.9% for neuroendocrine tumors, respectively), and the area under the receiver operating characteristic curves was higher than that of conventional EUS. The enhancement texture of CEH-EUS of the gallbladder masses showed a higher sensitivity in differentiating malignant masses than that of conventional EUS; however, the difference between the areas under the receiver operating characteristic curves was not statistically significant. CONCLUSIONS: CEH-EUS can complement conventional EUS in the diagnosis of pancreatic and gallbladder masses, in terms of the limitations of the latter.

Assessment of the Risk of Colorectal Cancer Survivors Developing a Second Primary Pancreatic Cancer

BACKGROUND/AIMS: We aimed to investigate the incidence of second primary pancreatic cancer (PC) after colorectal cancer (CRC) and to identify risk factors associated with subsequent PC. METHODS: The observed incidence of a subsequent PC in patients with CRC was standardized using a population with CRC from the Korean Central Cancer Registry (KCCR). The expected incidence rate of PC was obtained by assuming that the select group experienced the same cancer incidence as the corresponding general population in the KCCR. RESULTS: The registry included 4,822 patients with CRC aged 45 to 74 years, representing 16,725.1 person-years of follow-up. Thirteen patients (0.3%) were diagnosed with a subsequent PC, and the overall age-adjusted incidence of second primary PC was 269.6 per 100,000 cases. In contrast, the overall incidence of primary PC in the general population was 18.68 per 100,000 individuals. The standardized incidence ratio of subsequent PC was 14.44, which was significantly higher in patients with CRC than in the general population. Sex, diabetes mellitus, smoking, body mass index, and a history of receiving chemotherapy as a treatment for CRC did not increase the risk of subsequent development of PC. CONCLUSIONS: The risk of a second primary PC was higher in patients with CRC. Further studies are needed to identify the risk factors and generate a screening strategy for cancer survivors.

Cholecystectomy for Prevention of Recurrence after Endoscopic Clearance of Bile Duct Stones in Korea

PURPOSE: Cholecystectomy in patients with an intact gallbladder after endoscopic removal of stones from the common bile duct (CBD) remains controversial. We conducted a case-control study to determine the risk of recurrent CBD stones and the benefit of cholecystectomy for prevention of recurrence after endoscopic removal of stones from the CBD in Korean patients. MATERIALS AND METHODS: A total of 317 patients who underwent endoscopic CBD stone extraction between 2006 and 2012 were included. Possible risk factors for the recurrence of CBD stones including previous cholecystectomy history, bile duct diameter, stone size, number of stones, stone composition, and the presence of a periampullary diverticulum were analyzed. RESULTS: The mean duration of follow-up after CBD stone extraction was 25.4+/-22.0 months. A CBD diameter of 15 mm or larger [odds ratio (OR), 1.930; 95% confidence interval (CI), 1.098 to 3.391; p=0.022] and the presence of a periampullary diverticulum (OR, 1.859; 95% CI, 1.014 to 3.408; p=0.045) were independent predictive factors for CBD stone recurrence. Seventeen patients (26.6%) in the recurrence group underwent elective cholecystectomy soon after endoscopic extraction of CBD stones, compared to 88 (34.8%) in the non-recurrence group; the difference was not statistically significant (p=0.212). CONCLUSION: A CBD diameter of 15 mm or larger and the presence of a periampullary diverticulum were found to be potential predictive factors for recurrence after endoscopic extraction of CBD stones. Elective cholecystectomy after clearance of CBD stones did not reduce the incidence of recurrent CBD stones in Korean patients.

Novel Therapeutic Modalities for Metastatic Pancreatic Cancer / 대한췌담도학회지

Pancreatic cancer is still one of the most devastating cancers with less than 5% of 5-year survival even though the advances in modern medicine. Considering effective screening strategies and vaccinations has been improving clinical outcomes in other gastrointestinal malignancies, there is not yet effective tools for pancreatic cancer in earlier stage. Thus, about 80% of patients of pancreatic cancer are diagnosed as unsuitable for curative resection. Furthermore, recent experimental data suggest metastasis of pancreatic cancer can be developed in remarkably earlier stage during carcinogenesis. Based on these findings, systemic chemotherapy is the main therapeutic option for treating pancreatic cancer. However, the outcome of systemic chemotherapy is still disappointing even though recent data with FOLFIRINOX and nab-paclitaxel showed relatively promising. With advances in molecular technologies including next generation sequencing, the therapeutic paradigm for handling malignancies has been rapidly changing. The new wave of tailored or precision medicine leads to develop several novel therapeutic options like immune check point inhibitor or novel adoptive cell therapy. Herein, we will discuss the current status and perspectives of targeted therapy for pancreatic cancer.

Novel Therapeutic Modalities for Metastatic Pancreatic Cancer / 대한췌담도학회지

Pancreatic cancer is still one of the most devastating cancers with less than 5% of 5-year survival even though the advances in modern medicine. Considering effective screening strategies and vaccinations has been improving clinical outcomes in other gastrointestinal malignancies, there is not yet effective tools for pancreatic cancer in earlier stage. Thus, about 80% of patients of pancreatic cancer are diagnosed as unsuitable for curative resection. Furthermore, recent experimental data suggest metastasis of pancreatic cancer can be developed in remarkably earlier stage during carcinogenesis. Based on these findings, systemic chemotherapy is the main therapeutic option for treating pancreatic cancer. However, the outcome of systemic chemotherapy is still disappointing even though recent data with FOLFIRINOX and nab-paclitaxel showed relatively promising. With advances in molecular technologies including next generation sequencing, the therapeutic paradigm for handling malignancies has been rapidly changing. The new wave of tailored or precision medicine leads to develop several novel therapeutic options like immune check point inhibitor or novel adoptive cell therapy. Herein, we will discuss the current status and perspectives of targeted therapy for pancreatic cancer.

Concomitant Statin Use Has a Favorable Effect on Gemcitabine-Erlotinib Combination Chemotherapy for Advanced Pancreatic Cancer

PURPOSE: Erlotinib-gemcitabine combined chemotherapy is considered as the standard treatment for unresectable pancreatic cancer. This study aimed to determine the clinical factors associated with response to this treatment. MATERIALS AND METHODS: This retrospective study included 180 patients with unresectable pancreatic cancer who received ≥2 cycles of gemcitabine-erlotinib combination therapy as first-line palliative chemotherapy between 2006 and 2014. "Long-term response" was defined as tumor stabilization after >6 chemotherapy cycles. RESULTS: The median progression-free survival (PFS) and overall survival (OS) were 3.9 and 8.1 months, respectively. On univariate analysis, liver metastasis (p=0.023) was negatively correlated with long-term response. Locally advanced stage (p=0.017), a history of statin treatment (p=0.01), and carcinoembryonic antigen levels <4.5 (p=0.029) had a favorable effect on long-term response. On multivariate analysis, a history of statin treatment was the only independent favorable factor for long-term response (p=0.017). Prognostic factors for OS and PFS were significantly correlated with liver metastasis (p=0.031 and 0.013, respectively). A history of statin treatment was also significantly associated with OS after adjusting for all potential confounders (hazard ratio, 0.48; 95% confidence interval, 0.26-0.92; p=0.026). CONCLUSION: These results suggest that statins have a favorable effect on "long-term response" to gemcitabine-erlotinib chemotherapy in unresectable pancreatic cancer patients. Statins may have a chemoadjuvant role in stabilizing long-term tumor growth.

A Comparison of Gastrointestinal Toxicities between Intensity-Modulated Radiotherapy and Three-Dimensional Conformal Radiotherapy for Pancreatic Cancer

BACKGROUND/AIMS: Concurrent chemoradiotherapy (CCRT) is considered the treatment option for locally advanced pancreatic cancer, but accompanying gastrointestinal toxicities are the most common complication. With the introduction of three-dimensional conformal radiotherapy (3-D CRT) and intensity-modulated radiotherapy (IMRT), CCRT-related adverse events are expected to diminish. Here, we evaluated the benefits of radiation modalities by comparing gastrointestinal toxicities between 3-D CRT and IMRT. METHODS: Patients who received CCRT between July 2010 and June 2012 in Severance Hospital, Yonsei University College of Medicine, were enrolled prospectively. The patients underwent upper endoscopy before and 1 month after CCRT. RESULTS: A total of 84 patients were enrolled during the study period. The radiotherapy modalities delivered included 3D-CRT (n=40) and IMRT (n=44). The median follow-up period from the start of CCRT was 10.6 months (range, 3.8 to 29.9 months). The symptoms of dyspepsia, nausea/vomiting, and diarrhea did not differ between the groups. Upper endoscopy revealed significantly more gastroduodenal ulcers in the 3-D CRT group (p=0.003). The modality of radiotherapy (3D-CRT; odds ratio [OR], 11.67; p=0.011) and tumor location (body of pancreas; OR, 11.06; p=0.009) were risk factors for gastrointestinal toxicities. CONCLUSIONS: IMRT is associated with significantly fewer gastroduodenal injuries among patients treated with CCRT for pancreatic cancer.

Surveillance and Early Diagnosis of Pancreatic Cancer / 대한췌담도학회지

Pancreatic cancer is still one of the most dreadful malignancies with 5-year survival of 5%. The lack of effective diagnostic tools for early detection of pancreatic cancer is the major factor for the poor prognosis of pancreatic cancer. Considering the relatively lower incidence of pancreatic cancer, it seems to be reasonable to find and investigate the high risk group of pancreatic cancer rather than to screen general population. During the last 2 decades, several epidemiologic and genetic high risk groups of pancreatic cancer were found. Especially, western countries including US have been taking care of genetic high risk group and reported several meaningful outcomes. With advances of understanding molecular carcinogenesis and progression of pancreatic cancer, the effort to find specific biomarkers for both detection and treatment of pancreatic cancer has been overwhelmed. Various types of biomarkers including protein, microRNA, exosomes or circulating tumor cells itself have been under investigations. Although there has been no single biomarker which can overcome CA19-9 in serum to date. It will be worthwhile to wait for more potent biomarker which can be used for early diagnosis and treatment of pancreatic cancer in near future.

A Case of Alpha-cell Nesidioblastosis and Hyperplasia with Multiple Glucagon-producing Endocrine Cell Tumor of the Pancreas / 대한소화기학회지

Nesidioblastosis is a term used to describe pathologic overgrowth of pancreatic islet cells. It also means maldistribution of islet cells within the ductules of exocrine pancreas. Generally, nesidioblastosis occurs in beta-cell and causes neonatal hyperinsulinemic hypoglycemia or adult noninsulinoma pancreatogenous hypoglycemia syndrome. Alpha-cell nesidioblastosis and hyperplasia is an extremely rare disorder. It often accompanies glucagon-producing marco- and mircoadenoma without typical glucagonoma syndrome. A 35-year-old female was referred to our hospital with recurrent acute pancreatitis. On radiologic studies, 1.5 cm sized mass was noted in pancreas tail. Cytological evaluation with EUS-fine-needle aspiration suggested serous cystadenoma. She received distal pancreatectomy. The histologic examination revealed a 1.7 cm sized neuroendocrine tumor positive for immunohistochemical staining with glucagon antibody. Multiple glucagon-producing micro endocrine cell tumors were scattered next to the main tumor. Additionally, diffuse hyperplasia of pancreatic islets and ectopic proliferation of islet cells in centroacinar area, findings compatible to nesidioblastosis, were seen. These hyperplasia and almost all nesidioblastic cells were positive for glucagon immunochemistry. Even though serum glucagon level still remained higher than the reference value, she has been followed-up without any evidence of recurrence or hormone related symptoms. Herein, we report a case of alpha-cell nesidioblastosis and hyperplasia combined with glucagon-producing neuroendocrine tumor with literature review.

Clinicopathologic Characteristics Associated with Complications and Long-Term Outcomes of Endoscopic Papillectomy for Adenoma

PURPOSE: Endoscopic papillectomy (EP) is currently employed for the treatment of ampullary adenoma. This study aimed to evaluate the clinical, endoscopic, and histologic characteristics related to complications and long-term outcomes of EP. MATERIALS AND METHODS: Thirty-nine patients underwent EP for ampullary adenoma. Patients were grouped according to the occurrence of procedure-related complications: no complication group (n=28) and complication group (n=11). RESULTS: The overall complication rate was 28.2%. The most common complication was EP-related pancreatitis (n=7). Amylase (p=0.006) and lipase levels (p=0.007), 24 hours after EP, were significantly higher in the complication group, however, these levels did not differ at earlier times. As the tumor progressed from adenoma to cancer, the complete resection was significantly lessened (p=0.032). The duration of antiprotease injection during the hospital stay was significantly longer (p=0.017) and the transfusion requirements were significantly higher (p=0.018) in the complication group. During a median follow-up of 15 months, three lesions (10.3%) recurred among patients with complete resection (n=29) and five lesions (12.8%) recurred among enrolled patients. One patient with progressive recurrence from low-grade dysplasia to adenocarcinoma was noted during a follow-up of 22 months. CONCLUSION: If symptoms are present, amylase and lipase levels, 24 hours after EP, could help predict possible EP-related pancreatitis. Histologic diagnosis through resected specimens may result in complete resection. Patients with complications need a longer duration of antiprotease injection during their hospital stay and more transfusions. The recurrence rate was not significantly high in completely resected cases, however, there was a possibility of progressive recurrence.