Maintenance steroid therapy is associated with decreased risk of malignancy and better prognosis of patients with autoimmune pancreatitis: A multicenter cohort study in Japan.

BACKGROUND/OBJECTIVES: The association between autoimmune pancreatitis (AIP) and pancreatic cancer (PC) remains controversial. This study aimed to clarify the long-term prognosis and risk of malignancies in AIP patients in Japan. METHODS: We conducted a multicenter retrospective cohort study on 1364 patients with type 1 AIP from 20 institutions in Japan. We calculated the standardized incidence ratio (SIR) for malignancies compared to that in the general population. We analyzed factors associated with overall survival, pancreatic exocrine insufficiency, diabetes mellitus, and osteoporosis. RESULTS: The SIR for all malignancies was increased (1.21 [95 % confidence interval: 1.05-1.41]) in patients with AIP. Among all malignancies, the SIR was highest for PC (3.22 [1.99-5.13]) and increased within 2 years and after 5 years of AIP diagnosis. Steroid use for ≥6 months and ≥50 months increased the risk of subsequent development of diabetes mellitus and osteoporosis, respectively. Age ≥65 years at AIP diagnosis (hazard ratio [HR] = 3.73) and the development of malignancies (HR = 2.63), including PC (HR = 7.81), were associated with a poor prognosis, whereas maintenance steroid therapy was associated with a better prognosis (HR = 0.35) in the multivariate analysis. Maintenance steroid therapy was associated with a better prognosis even after propensity score matching for age and sex. CONCLUSIONS: Patients with AIP are at increased risk of developing malignancy, especially PC. PC is a critical prognostic factor for patients with AIP. Although maintenance steroid therapy negatively impacts diabetes mellitus and osteoporosis, it is associated with decreased cancer risk and improved overall survival.

Factors affecting complete stone removal and bile duct stone recurrence in patients with surgically altered anatomy treated by double-balloon endoscopy-assisted endoscopic retrograde cholangiography.

OBJECTIVES: This study assessed factors influencing the complete removal and recurrence of bile duct stones in patients with surgically altered anatomy (SAA) undergoing double-balloon endoscopy-assisted endoscopic retrograde cholangiography (DBERC). METHODS: A retrospective analysis of 289 patients with SAA treated for biliary stones with DBERC at Jichi Medical University Hospital (January 2007 to December 2022) was conducted. Evaluation of factors impacting complete stone removal was performed in 257 patients with successful bile duct cannulation. Logistic and Cox proportional hazards regression models were used to compute the odds ratios (ORs) and hazard ratios (HRs) at 95% confidence intervals (CIs). RESULTS: Of 257 patients, 139 (54.0%) and 209 (81.3%) achieved initial and complete removal, respectively. Recurrence occurred in 55 (21.4%) patients. Factors associated with initial complete stone removal included cholangitis (P < 0.01, OR 0.48, 95% CI 0.27-0.83), number of stones (P < 0.01, OR 0.31, 95% CI 0.18-0.54), and largest stone diameter (P < 0.01, OR 0.37, 95% CI 0.20-0.67). The size of the largest stone was associated with complete removal (P = 0.01, OR 0.24, 95% CI 0.13-0.76). Recurrence was associated with cholangitis (P = 0.046, HR 0.54, 95% CI 0.29-0.99), congenital biliary dilatation (P = 0.01, HR 2.65, 95% CI 1.21-5.80), and number of stones (P = 0.02, HR 1.96, 95% CI 1.12-3.41). CONCLUSIONS: Successful complete bile stone removal in patients with SAA depends on the stone diameter and number. Stone recurrence is influenced by the number of stones and history of congenital biliary dilatation.

Single-pixel optical modulation analyzer based on phase retrieval for dual-polarization IQ modulators.

In-service monitoring and adaptive digital compensation of analog imperfections in optical transponders are vital in the next-generation optical coherent transmission systems employing extremely high-order, high-speed modulation formats. A notable example of such analog impairments is the imbalance of amplitude, phase, and/or timing between the in-phase (I) and quadrature (Q) tributaries in an optical IQ modulator, namely the IQ imbalance. Recently, an IQ-imbalance estimation technique based on phase retrieval without using a coherent receiver, the so-called single-pixel optical modulation analyzer (SP-OMA), has been proposed as an affordable in-service monitoring solution for the frequency-dependent IQ imbalance in a (single-polarization) IQ modulator. In this work, we extend the concept of the SP-OMA to dual-polarization IQ modulators. A novel phase retrieval algorithm with an alternating minimization procedure is proposed for identifying the frequency-dependent IQ imbalances on both polarization channels simultaneously from a single photodetector output. The validity and feasibility of the proposed SP-OMA for a dual-polarization IQ modulator are demonstrated numerically and experimentally with a 63.25-Gbaud DP-16QAM signal.

Carrier conversion from terahertz wave to dual-wavelength near-infrared light for photonic terahertz detection in wireless communication.

THz waves are promising wireless carriers for next-generation wireless communications, where a seamless connection from wireless to optical communication is required. In this study, we demonstrate carrier conversion from THz waves to dual-wavelength NIR light injection-locking to an optical frequency comb using asynchronous nonpolarimetric electro-optic downconversion with an electro-optic polymer modulator. THz wave in the W band was detected as a stable photonic RF beat signal of 1 GHz with a signal-to-noise ratio of 20 dB via the proposed THz-to-NIR carrier conversion. In addition, the results imply the potential of the photonic detection of THz waves for wireless-to-optical seamless communication.

Temperature-independent lasing wavelength of highly stacked InAs quantum dot laser fabricated on InP(311)B substrate with Bi irradiation.

In this study, the effects of bismuth (Bi) irradiation on InAs quantum dot (QD) lasers operating in the telecommunication wavelength band were investigated. Highly stacked InAs QDs were grown on an InP(311)B substrate under Bi irradiation, and a broad-area laser was fabricated. In the lasing operation, the threshold currents were almost the same, regardless of Bi irradiation at room temperature. These QD lasers were operated at temperatures between 20 and 75°C, indicating the possibility of high-temperature operation. In addition, the temperature dependence of the oscillation wavelength changed from 0.531 nm/K to 0.168 nm/K using Bi in the temperature range 20-75°C.

The Ki67 index evaluation of pancreatic neuroendocrine tumors using 3D immunohistochemistry in small tissue specimens.

BACKGROUND: /Objectives: This study aimed to evaluate the usefulness of three-dimensional (3D) immunohistochemistry for the Ki67 index of small tissue specimens of pancreatic neuroendocrine tumor (PanNET). METHODS: Clinicopathological materials from 17 patients with PanNET who underwent surgical resection at Jichi Medical University Hospital were analyzed. We compared the Ki67 index of endoscopic ultrasonography-fine-needle aspiration biopsy (EUS-FNAB) specimens, surgical specimens, and small tissue specimens hollowed from paraffin blocks of surgical specimens that were substituted for EUS-FNAB specimens ("sub-FNAB"). The sub-FNAB specimens were optically cleared using LUCID (IlLUmination of Cleared organs to IDentify target molecules) and analyzed using 3D immunohistochemistry. RESULTS: The median Ki67 index in FNAB, sub-FNAB, and surgical specimens with conventional immunohistochemistry were 1.2% (0.7-5.0), 2.0% (0.5-14.6), and 5.4% (1.0-19.4), respectively. The median Ki67 index in sub-FNAB specimens with tissue clearing was calculated separately using the total number of cells on multiple images ("multiple slice"), with the image of the fewest positive cells ("coldspot"), and with the image of most positive cells ("hotspot"), which were 2.7% (0.2-8.2), 0.8% (0-4.8), and 5.5% (2.3-12.4), respectively. PanNET grade evaluated for the hotspot of the surgical specimens was significantly more consistent with those of the hotspot than multiple images of sub-FNAB specimens (16/17 vs. 10/17, p = 0.015). Hotspot evaluation using 3D immunohistochemistry of the sub-FNAB specimens showed agreement with the assessment of the surgical specimens (Kappa coefficient: 0.82). CONCLUSIONS: Tissue clearing and 3D immunohistochemistry for the Ki67 index can potentially improve the preoperative evaluation of EUS-FNAB specimens of PanNET in routine clinical practice.

Millimeter Wave Attenuation Due to Wind and Heavy Rain in a Tropical Region.

Millimeter wave fixed wireless systems in future backhaul and access network applications can be affected by weather conditions. The losses caused by rain attenuation and antenna misalignment due to wind-induced vibrations have greater impacts on the link budget reduction at E-band frequencies and higher. The current International Telecommunications Union Radiocommunication Sector (ITU-R) recommendation has been widely used to estimate rain attenuation, and the recent Asia Pacific Telecommunity (APT) report provides the model to estimate the wind-induced attenuation. This article provides the first experimental study of the combined rain and wind effects in a tropical location using both models at a frequency in the E band (74.625 GHz) and a short distance of 150 m. In addition to using wind speeds for attenuation estimation, the setup also provides direct antenna inclination angle measurements using the accelerometer data. This solves the limitation of relying on the wind speed since the wind-induced loss is dependent on the inclination direction. The results show that the current ITU-R model can be used to estimate the attenuation of a short fixed wireless link under heavy rain, and the addition of wind attenuation via the APT model can estimate the worst-case link budget during high wind speeds.

High-speed fiber-wireless-fiber system in the 100-GHz band using a photonics-enabled receiver and optical phase modulator.

This Letter describes a high-speed yet simple fiber-wireless-fiber system in the 100-GHz band using a photonics-enabled receiver and optical phase modulator. At the antenna site, a millimeter-wave signal is down-converted to the microwave band using an electronic mixer with a local oscillator signal generated remotely using photonic technology. The down-converted signal is converted to an optical signal using an optical phase modulator. At the receiver, a simple direct detection of the phase-modulated signal is performed using optical filtering technology. To demonstrate the proof-of-concept, we successfully transmitted a 64-quadrature amplitude modulation orthogonal frequency-division multiplexing signal with a record line rate of 80 Gb/s (net data rate of 55 Gb/s) over a system consisting of two radio-over-fiber links and a 5 m wireless link in the 100-GHz band. The proposed system with simple antenna sites and optical transceivers can facilitate the deployment of ultra-dense small cells in high-frequency bands in beyond-5G networks.

Fifth-generation new radio millimeter-wave radio signal transmission over a seamless fiber-terahertz mobile fronthaul system for an ultra-dense small cell network.

This Letter demonstrates the transmission of fifth-generation new radio (5G NR) millimeter-wave signals over a seamless fiber-terahertz-wave mobile fronthaul system in the 350 GHz band for an ultra-dense small cell network. The system utilizes a simple optical heterodyne method at the transmitter and direct detection at the receiver. As a proof-of-concept demonstration, we successfully transmitted 256- and 64-quadrature amplitude modulation 5G-NR-compliant signals at 24.2 and 38 GHz over a seamless fiber-terahertz system in the 350 GHz band. The proposed system can provide a simple solution to facilitate the deployment of ultra-dense small cells in high-frequency bands in 5G networks and beyond.

Endoscopic ultrasound-guided pancreatic sampling for the histopathological diagnosis of autoimmune pancreatitis.

Autoimmune pancreatitis (AIP), which is characterized by pancreatic enlargement and irregular narrowing of the main pancreatic duct, is difficult to differentiate from malignancy. The irregular narrowing of the pancreatic duct, which can be detected via endoscopic retrograde cholangiopancreatography, is a characteristic feature of AIP; however, distinguishing between localized AIP and pancreatic cancer based on pancreatic duct imaging is difficult. This study overviews the efficacy of endoscopic ultrasound (EUS)-guided pancreatic sampling for the histopathological diagnosis of AIP. Recent enhancements in needle biopsy methodologies and technologies have contributed to improvement in the diagnostic efficacy of this technique. The guidance provided in this study for the histological diagnosis of AIP is anticipated to further advance in the histopathological diagnosis of AIP using EUS-guided pancreatic sampling.

Tissue harmonic versus contrast-enhanced harmonic endoscopic ultrasonography for the diagnosis of pancreatic tumors: Prospective multicenter study.

OBJECTIVES: This prospective multicenter study aimed to assess and compare the accuracy of tissue harmonic endoscopic ultrasonography (TH-EUS) and contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) for differentiating pancreatic carcinoma from other pancreatic tumors. METHODS: Consecutive patients with solid pancreatic tumors were prospectively enrolled between August 2013 and December 2014. To assess the accuracy of TH-EUS and CH-EUS, we compared four parameters of TH-EUS (fuzzy edge, irregular periphery, hypoechogenicity, and heterogeneous internal echogenicity) and four parameters of CH-EUS (hypoenhancement and heterogeneous enhancement in the early and late phases, respectively) to investigate which parameter of each method was most suitable to diagnose pancreatic carcinomas. Interobserver agreement and the diagnostic ability of pancreatic carcinoma using TH-EUS and CH-EUS were assessed and compared. RESULTS: A total of 204 patients were enrolled. For the diagnosis of pancreatic carcinoma, interobserver agreement by experts and nonexperts was 0.33-0.50 and 0.35-0.50 for TH-EUS, respectively, and 0.72-0.74 and 0.20-0.54 for CH-EUS, respectively. Irregular periphery was the most accurate diagnostic parameter among TH-EUS findings for differentiating pancreatic carcinomas, with sensitivity, specificity, and accuracy of 95.0%, 42.9%, and 78.9%, respectively. Late phase hypoenhancement was the most accurate diagnostic parameter among CH-EUS findings for differentiating pancreatic carcinomas, with sensitivity, specificity, and accuracy of 90.8%, 74.6%, and 85.8%, respectively. The accuracy of CH-EUS (late phase hypoenhancement) for diagnosis of pancreatic carcinoma was significantly higher than that of TH-EUS (irregular periphery) (p < 0.001). CONCLUSION: In comparison with TH-EUS, CH-EUS increased the diagnostic ability and reproducibility for the diagnosis of pancreatic carcinoma. UMIN (000011124).

High-fidelity indoor MIMO radio access for 5G and beyond based on legacy multimode fiber and real-time analog-to-digital-compression.

Dedicated indoor radio access network (RAN, such as C-RAN with fronthaul) will be in urgent demand for 5G and beyond ((B)5G), as it becomes more difficult for outdoor base stations to serve indoor mobile/IoT terminals due to the loss issue induced by higher carrier frequency. One cost-effective and time-saving strategy for indoor (B)5G RAN is to reuse the legacy multimode fibers (MMF) deployed in buildings and premises worldwide. In this work, we introduce the concept of indoor (B)5G fronthaul over legacy MMF based on analog-to-digital-compression (ADX), termed as ADX-RoMMF. Enabled by ADX for MIMO data compression, both high radio signal fidelity and fronthaul bandwidth efficiency can be achieved, which alleviates the limitation of low MMF bandwidth-distance product and supports decent indoor coverage. Meanwhile, its digital nature is highly compatible with low-cost optical transceivers (with nonlinearity and/or imperfection) and packet-based fronthaul networking such as time-sensitive networking. Furthermore, the ultralow latency of ADX processing meets the requirement of low-delay (B)5G fronthauling. We experimentally demonstrate an ADX-RoMMF link serving 16-channel MIMO signals with NR-class bandwidth and 1024QAM, leveraging a real-time ADX prototyped on a single-chip field-programmable radio platform. Results show that this 32Gb/s CPRI-equivalent rate can be transported over MMF distance of 850m within 1024QAM EVM requirement, which is 4-fold larger than that of conventional fronthaul compression scheme. Moreover, 500ns ADX latency overhead is also verified.

Single-pixel optical modulation analyzer: a low-complexity frequency-dependent IQ imbalance monitor based on direct detection with phase retrieval.

Tiny mismatches in timing, phase, and/or amplitude between in-phase (I) and quadrature (Q) tributaries in an electro-optic IQ modulator, namely IQ imbalance, can severely affect high baud-rate and/or high modulation-order signals in modern coherent optical communications systems. To maintain such analog impairment within the tight penalty limit over wavelength and temperature during the product lifetime, in-service in-field monitoring and calibration of the IQ imbalance, including its frequency dependence, become increasingly important. In this study, we propose a low-complexity IQ monitoring technique based on direct detection with phase retrieval called a single-pixel optical modulation analyzer (SP-OMA). By reconstructing the optical phase information lost during the detection process computationally via phase retrieval, SP-OMA facilitates the in-service in-field monitoring of the frequency-dependent imbalance profile without sending dedicated pilot tones and regardless of any receiver/monitor-side IQ imbalance. The feasibility of SP-OMA is demonstrated both numerically and experimentally with a 63.25-Gbaud 16QAM signal.

Superconducting acousto-optic phase modulator.

We report the development of a superconducting acousto-optic phase modulator fabricated on a lithium niobate substrate. A titanium-diffused optical waveguide is placed in a surface acoustic wave resonator, where the electrodes for mirrors and an interdigitated transducer are made of a superconducting niobium titanium nitride thin film. The device performance is evaluated as a substitute for the current electro-optic modulators, with the same fiber coupling scheme and comparable device size. Operating the device at a cryogenic temperature (T = 8 K), we observe the length-half-wave-voltage (length-Vπ) product of 1.78 V·cm. Numerical simulation is conducted to reproduce and extrapolate the performance of the device. An optical cavity with mirror coating on the input/output facets of the optical waveguide is tested for further enhancement of the modulation efficiency. A simple extension of the current device is estimated to achieve an efficient modulation with Vπ = 0.27 V.

Millimeter-wave radio-over-fiber system using optical phase modulation and photonic downconversion for uplink fronthaul transmission.

This Letter proposes a high-performance radio-over-fiber (RoF) system for high-speed and high-fidelity analog waveform transmission of radio signals in the millimeter-wave band in the uplink direction. At the antenna site, the system utilizes a newly fabricated low half-wave voltage broadband phase modulator to convert a millimeter-wave radio signal into an optical signal. At the receiver, by using photonic downconversion and optical filtering technology, a simple direct detection and downconversion of the signal to the microwave band can be achieved simultaneously. As a demonstration of proof of concept, we successfully transmitted a 1024-quadrature amplitude modulation (QAM) narrowband orthogonal frequency-division multiplexing signal at 38 GHz and a 60 Gb/s 64-QAM single-carrier signal at 26.5 GHz over a 20 km RoF system. The system is promising for facilitating the deployment of ultra-dense small cells in high-frequency bands in 5G and beyond networks.

Adverse events of endoscopic ultrasound-guided fine-needle aspiration for histologic diagnosis in Japanese tertiary centers: Multicenter retrospective study.

BACKGROUND AND AIMS: Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is used for the histopathological diagnosis of any type of gastrointestinal disease. Few adverse events are experienced with this procedure; however, the actual rate of adverse events remains unclear. This study aimed to clarify the current status of cases that experienced adverse events related to the EUS-FNA procedure used for histopathologic diagnoses. METHODS: A retrospective analysis of cases with EUS-FNA-related adverse events in Japanese tertiary centers was conducted by assessing the following clinical data: basic case information, FNA technique, type of procedural adverse events, and prognosis. RESULTS: Of the 13,566 EUS-FNA cases overall, the total number of cases in which adverse events related to EUS-FNA occurred was 234. The incidence of EUS-FNA-related adverse events was ~1.7%. Bleeding and pancreatitis cases accounted for ~49.1% and 26.5% of all adverse events, respectively. Bleeding was the most common adverse event with only seven cases requiring blood transfusion. In cases with neuroendocrine tumors, pancreatitis was the most frequent adverse event. Needle tract seeding because of EUS-FNA was observed during the follow-up period in only ~0.1% of cases with pancreatic cancer. There was no mortality because of adverse events caused by EUS-FNA. CONCLUSIONS: This study revealed that the adverse events-related EUS-FNA for histopathologic diagnoses were not severe conditions, and had low incidence.

New Model for Predicting Malignancy in Patients With Intraductal Papillary Mucinous Neoplasm.

OBJECTIVE: To create a simple, objective model to predict the presence of malignancy in patients with intraductal papillary mucinous neoplasm (IPMN), which can be easily applied in daily practice and, importantly, adopted for any lesion types. BACKGROUND: No predictive model for malignant IPMN has been widely applied in clinical practice. METHODS: The clinical details of 466 patients with IPMN who underwent pancreatic resection at 3 hospitals were retrospectively analyzed for model development. Then, the model was validated in 664 surgically resected patients at 8 hospitals in Japan.In the preoperative examination, endoscopic ultrasonography (EUS) was considered to be essential to observe mural nodules in both the model development and external validation sets. Malignant IPMNs were defined as those with high-grade dysplasia and associated invasive carcinoma. RESULTS: Of the 466 patients, 258 (55%) had malignant IPMNs (158 high-grade dysplasia, 100 invasive carcinoma), and 208 (45%) had benign IPMNs. Logistic regression analysis resulted in 3 variables (mural nodule size, main pancreatic duct diameter, and cyst size) being selected to construct the model. The area under the receiver operating characteristic curve (AUC) for the model was 0.763. In external validation sets, the pathological diagnosis was malignant and benign IPMN in 351 (53%) and 313 (47%) cases, respectively. For the external validation, the malignancy prediction ability of the model corresponded to an AUC of 0.725. CONCLUSION: This predictive model provides important information for physicians and patients in assessing an individual's risk for malignancy and may help to identify patients who need surgery.

Efficacy and limitations of the histological diagnosis of type 1 autoimmune pancreatitis with endoscopic ultrasound-guided fine needle biopsy with large tissue amounts.

OBJECTIVES: We examined the efficacy and limitations of acquiring large specimens by endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) for diagnosing type 1 autoimmune pancreatitis (AIP). METHODS: Patients from 12 institutions with non-neoplastic diseases or pancreatic ductal adenocarcinoma (PDAC) with large EUS-FNB specimens were investigated. Slides stained with hematoxylin-eosin, elastic, IgG4, and IgG stains were evaluated. The IgG4- and IgG-positive cell numbers were counted in three foci. The diagnoses were based on the Japan Pancreas Society 2011 (JPS 2011) criteria and the International Consensus Diagnostic Criteria (ICDC). RESULTS: We analyzed 85 non-neoplastic (definite type 1 AIP in 73/85 based on the ICDC) cases and 64 PDAC cases. IgG4-positive cells were numerous (>10 in 85.9%), and the IgG4/IgG ratios were high (>40% in 81.2%). Plasma cell crushing by an artifact caused unsuccessful immunostaining, notably in smaller samples. Tissue lengths were an important factor for the presence of storiform fibrosis and obliterative phlebitis, but storiform fibrosis was equivocal even in large tissues. A definite or possible histological diagnosis was achieved in 45.9% (39/85) and 41.2% (35/85), respectively, and contributed to the definite final diagnosis of type 1 AIP in 33.3% (ICDC) and 55.6% (JPS 2011) in cases with segmental/focal lesions. In the PDAC group, >10 IgG4-positive cells was rare (2/58), but elastic stains revealed fibrous venous occlusions in 10.3% (6/58). CONCLUSIONS: EUS-FNB with large tissue amounts was useful for diagnosing type 1 AIP, notably by facilitating successful IgG4 immunostaining, but definite diagnosis may not be achieved even in cases with large specimens.

Pancreatic neuroendocrine carcinoma G3 may be heterogeneous and could be classified into two distinct groups.

BACKGROUND/OBJECTIVES: Pancreatic neuroendocrine carcinoma (PanNEC)-G3 often presents along with genetic abnormalities such as KRAS, RB1, and TP53 mutations. However, the association between these genetic findings and response to chemotherapy and prognosis has not been clarified. This study aimed to clarify the clinicopathological features of PanNEC-G3. METHODS: We performed a subgroup analysis of the Japanese PanNEN-G3 study (multicenter, retrospective study), which revealed that Rb loss and KRAS mutation were predictors of the response to platinum-based regimen in PanNEN-G3. We re-classified WHO grades of PanNENs using the 2017 WHO classification and then analyzed the clinicopathological features and prognostic factors in 49 patients with PanNEC-G3. RESULTS: The rates of Rb loss and KRAS mutation in PanNEC-G3 were 54.5% and 48.7%, respectively. Patients with Rb loss and/or KRAS mutation showed a higher response rate to first-line platinum-based regimen than those without Rb loss or KRAS mutation (object response rate 70.0% vs 33.3%, odds ratio 9.22; 95% CI 1.26-67.3, P = 0.029), but tended to have shorter overall survival rates than those without Rb loss or KRAS mutation (median 239 vs 473 days, hazard ratio 2.11; 95% CI 0.92-4.86, P = 0.077). CONCLUSIONS: Patients with PanNEC-G3 have varied clinical outcomes for platinum-based regimen. When grouped based on Rb loss and KRAS mutation, there seemed to be two groups with distinct prognoses and responses to the platinum-based regimen. PanNEC-G3 could, therefore, be classified into two distinct groups based on immunohistochemical and genetic findings.

International consensus guidelines on interventional endoscopy in chronic pancreatitis. Recommendations from the working group for the international consensus guidelines for chronic pancreatitis in collaboration with the International Association of Pancreatology, the American Pancreatic Association, the Japan Pancreas Society, and European Pancreatic Club.

BACKGROUND/OBJECTIVES: This paper is part of the international consensus guidelines on chronic pancreatitis, presenting for interventional endoscopy. METHODS: An international working group with experts on interventional endoscopy evaluated 26 statements generated from evidence on 9 clinically relevant questions. The Grading of Recommendations Assessment, Development, and Evaluation approach was used to evaluate the level of evidence. To determine the level of agreement, a nine-point Likert scale was used for voting on the statements. RESULTS: Strong consensus was obtained for 15 statements relating to nine questions including the recommendation that endoscopic intervention should be offered to patients with persistent severe pain but not to those without pain. Endoscopic decompression of the pancreatic duct could be used for immediate pain relief, and then offered surgery if this fails or needs repeated endoscopy. Endoscopic drainage is preferred for portal-splenic vein thrombosis and pancreatic fistula. A plastic stent should be placed and replaced 2-3 months later after insertion. Endoscopic extraction is indicated for stone fragments remaining after ESWL. Interventional treatment should be performed for symptomatic/complicated pancreatic pseudocysts. Endoscopic treatment is recommended for bile duct obstruction and afterwards surgery if this fails or needs repeated endoscopy. Surgery may be offered if there is significant calcification and/or mass of the pancreatic head. Percutaneous endovascular treatment is preferred for hemosuccus pancreaticus. Surgical treatment is recommended for duodenal stenosis due to chronic pancreatitis. CONCLUSIONS: This international expert consensus guideline provides evidenced-based statements concerning indications and key aspects for interventional endoscopy in the management of patients with chronic pancreatitis.