High-grade pancreatic intraepithelial neoplasia diagnosed based on changes in magnetic resonance cholangiopancreatography findings: A case report.

BACKGROUND: High-grade pancreatic intraepithelial neoplasia (PanIN) exhibits no mass and is not detected by any examination modalities. However, it can be diagnosed by pancreatic juice cytology from indirect findings. Most previous cases were diagnosed based on findings of a focal stricture of the main pancreatic duct (MPD) and caudal MPD dilatation and subsequent pancreatic juice cytology using endoscopic retrograde cholangiopancreatography (ERCP). We experienced a case of high-grade PanIN with an unclear MPD over a 20-mm range, but without caudal MPD dilatation on magnetic resonance cholangiopancreatography (MRCP). CASE SUMMARY: A 60-year-old female patient underwent computed tomography for a follow-up of uterine cancer post-excision, which revealed pancreatic cysts. MRCP revealed an unclear MPD of the pancreatic body at a 20-mm length without caudal MPD dilatation. Thus, course observation was performed. After 24 mo, MRCP revealed an increased caudal MPD caliber and a larger pancreatic cyst. We performed ERCP and detected atypical cells suspected of adenocarcinoma by serial pancreatic juice aspiration cytology examination. We performed a distal pancreatectomy and obtained a histopathological diagnosis of high-grade PanIN. Pancreatic parenchyma invasion was not observed, and curative resection was achieved. CONCLUSION: High-grade Pan-IN may cause MPD narrowing in a long range without caudal MPD dilatation.

Usefulness of an ultrathin endoscope for guidewire insertion during stent-in-stent placement.

Video 1Stent-in-stent placement using an ultrathin endoscope.

Efficacy of a novel integrated biliary stent and nasobiliary catheter system for accidental tube deviation in biliary drainage.

Background and study aims Endoscopic nasobiliary drainage is accompanied by a risk of accidental removal of the nasobiliary drainage (NBD) tube, especially through self-removal in elderly patients. We studied the usefulness of an integrated biliary stent and nasobiliary catheter system (UMIDAS NB stent) for biliary drainage in case of accidental NBD tube removal. Patients and methods From April to November 2022, we placed a UMIDAS NB stent in 30 patients with acute cholangitis or obstructive jaundice. We evaluated the plastic stent (PS) position at the time of accidental stent removal and before the planned endoscopic procedure. In addition, we studied the ratio of successful biliary drainage and complications based on the usage of UMIDAS. Results All 11 patients with accidental stent removal exhibited correct PS position in X-ray fluoroscopy. Of the 19 patients with planned NBD tube removal, three had complete PS migration into the common bile duct and three had incomplete migration (the duodenal side flap entered the bile duct). In summary, 80% (24/30) of PS were in the correct position, and all patients had successful biliary drainage and no complications. Conclusions The UMIDAS NB stent might be useful for biliary drainage in patients with a high risk of NBD tube self-removal.

Clinical features and images of malignant lymphoma localized in the pancreatic head to differentiate from pancreatic ductal adenocarcinoma: a case series study.

BACKGROUND: Pathological examination by endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA) has been reported to be useful in diagnosing pancreatic malignant lymphoma (ML), but some ML cases are difficult to be differentiated from pancreatic ductal adenocarcinoma (PDAC). METHODS: This retrospective study included 8 patients diagnosed with ML that had a pancreatic-head lesion at initial diagnosis and 46 patients with resected PDAC in the pancreatic head between April 2006 and October 2021 at our institute. ML and PDAC were compared in terms of patients' clinical features and imaging examinations. RESULTS: The median tumor size was larger in ML than in PDAC (45.8 [24-64] vs. 23.9 [8-44] mm), but the median diameter of the caudal main pancreatic duct (MPD) was larger in PDAC (2.5 [1.0-3.5] vs. 7.1 [2.5-11.8] mm), both showing significant differences between these malignancies (both, P < 0.001). In the analysis of covariance, MLs showed a smaller caudal MPD per tumor size than PDACs, with a statistical difference (P = 0.042). Sensitivity and specificity using sIL-2R ≥ 658 U/mL plus CA19-9 < 37 U/mL for the differentiation of ML from PDAC were 80.0% and 95.6%, respectively. CONCLUSIONS: Diagnosing pancreatic ML using cytohistological examination through EUS-FNA can be difficult in some cases. Thus, ML should be suspected if a patient with a pancreatic tumor has a small MPD diameter per tumor size, high serum sIL-2R level, normal CA19-9 level. If the abovementioned features are present and still cannot be confirmed as PDAC, re-examination should be considered.

Metastatic pancreatic ductal adenocarcinoma followed by a fatal diffuse large B-cell lymphoma: A rare case report and literature review.

RATIONALE: Recently, the incidence of polyoncosis has been increasing due to advancements in treatment, such as antitumor therapy, which led to a prolonged survival. However, few patients with metastatic pancreatic ductal adenocarcinoma (PDAC) develop second tumors, which render a poor prognosis. We report a rare case of PDAC, which is metachronous with a fatal malignant lymphoma (ML). PATIENT CONCERNS: A 68-year-old woman who had been monitored due to liver cirrhosis secondary to hepatitis C virus infection presented with a 10-mm pancreatic head cancer with lung metastasis and had started an anticancer therapy with gemcitabine. Approximately 18 months after diagnosis, lymphadenopathies around the pancreas were noted, which eventually spread to the entire body over time. DIAGNOSIS: Diffuse large B-cell lymphoma was diagnosed using biopsies from cervical lymph nodes. INTERVENTIONS AND OUTCOMES: The patient started a gemcitabine + rituximab regimen; however, the patient died from cachexia-associated lymphoma progression, not PDAC. LESSONS: ML should be considered when intra-abdominal lymphadenopathies are detected in patients with pancreatic cancer, and ML should be differentiated from lymph node metastasis of pancreatic cancer.

Effectiveness of Abdominal Ultrasonography for Improving the Prognosis of Pancreatic Cancer during Medical Checkup: A Single Center Retrospective Analysis.

Recent advancements in surgical and anti-cancer therapies have provided significant hope of long survival in patients with pancreatic cancer (PC). To realize this hope, routine medical checkups of asymptomatic people should be performed to identify operable PCs. In this study, we evaluated the efficacy of medical checkups using abdominal ultrasonography (US). We retrospectively analyzed 374 patients with PC at our institute between 2010 and 2021. We divided these patients into several groups according to the diagnostic approach and compared their background and prognosis. These groups comprised PCs diagnosed through (a) symptoms, 242 cases; (b) US during medical checkup for asymptomatic individuals, 17; and other means. Of the 374 patients, 192 were men (51.3%), and the median age was 74 years (34−105). Tumors were located in the pancreatic tail in 67 patients (17.9%). Excision ratio and 5-year survival rate were significantly better in group (b) than in (a) (58.8% vs. 23.1%, p < 0.01 and 42.2% vs. 9.4%, p < 0.001, respectively). The prognosis of patients diagnosed using US during medical checkup was better than that of patients identified through symptomatic presentation of PC. US for asymptomatic individuals with PC might be one of the useful modalities for promoting better prognosis of PCs.

Factors for conversion risk of colorectal endoscopic submucosal dissection: a multicenter study.

BACKGROUND: Endoscopic submucosal dissection (ESD) has become a widely accepted treatment method for colorectal tumors; however, there are some persistent problems. This multi-center study aimed to characterize the risk factors for incomplete resection and perforation in standardized colorectal ESD procedures. METHODS: This study included 2423 consecutive patients who underwent ESD for 2592 colorectal tumors between August 2013 and December 2018 at 11 institutions (1 academic hospital and 10 affiliated hospitals) from the Hiroshima GI Endoscopy Research Group. We evaluated the risk factors for interruption, piecemeal resection, and perforation of standardized colorectal ESD in relation to clinicopathologic and endoscopic characteristics. RESULTS: The incidences of interruption, piecemeal resection, and perforation were 0.7%, 2.9%, and 3.0%, respectively. Multivariate analysis identified the following risk factors for interruption: perforation during the procedure, deep submucosal invasion (> 1000 µm), poor scope operability, and severe submucosal fibrosis. The risk factors for piecemeal resection included poor scope operability, severe submucosal fibrosis, and procedure time (≥ 85 min). The risk factors for perforation during the procedure were severe submucosal fibrosis, poor scope operability, procedure time (≥ 85 min), and tumor size (≥ 40 mm). Independent risk factors for severe submucosal fibrosis included a history of biopsy and lesions located on the fold or flexure. CONCLUSIONS: Severe submucosal fibrosis and poor scope operability are the common risk factors for interruption, piecemeal resection, and perforation in standardized colorectal ESD.

Efficacy and safety comparison of scissor-type knives with needle-type knives for colorectal endoscopic submucosal dissection: a post-hoc propensity score-matched analysis (with videos).

BACKGROUND AND AIMS: Many knives have been developed to improve the efficacy and safety of endoscopic submucosal dissection (ESD). We aimed to evaluate the efficacy and safety of scissor-type knives for colorectal ESD compared with needle-type knives. METHODS: We performed a post-hoc propensity score-matched analysis in an 11-facility study between August 2013 and December 2018. A total of 2330 patients (2498 lesions) who underwent colorectal ESD were divided into needle-type (1923 patients, 2067 lesions) and scissor-type (407 patients, 431 lesions) knife groups. Short-term outcomes were compared between the 2 groups. RESULTS: Two-to-one propensity score-matched analysis identified 814 (709 patients) and 407 (386 patients) lesions in the needle- and scissor-type knife groups, respectively. The median resection speed was significantly faster in the needle-type group (18.3 mm2/min) than in the scissor-type group (13.2 mm2/min, P < .0001), whereas en-bloc and histologic complete resection rates were not significantly different between the needle- and scissor-type groups (96.8% [788/814] vs 98.3% [400/407], P = .1888 and 95.1% [774/814] vs 95.6% [389/407], P = .7763, respectively). The rate of lesions resected using a single knife was significantly higher in the scissor-type group (98.5% [401/407]) than in the needle-type group (43.9% [357/814], P < .0001). Rates of intraoperative perforation and delayed bleeding were significantly lower in the scissor-type group than in the needle-type group (.7% [3/407] vs 2.5% [20/814], P = .0431 for each). CONCLUSIONS: Scissor-type knives are safer for colorectal ESD. However, they are associated with slower resection speeds compared with needle-type knives. (Clinical trial registration number: UMIN000016197.).

Indications and outcomes of colorectal hybrid endoscopic submucosal dissection: a large multicenter 10-year study.

BACKGROUND AND AIMS: Hybrid endoscopic submucosal dissection (ESD) is a colorectal lesion resection procedure that includes both planned and salvage procedures. Previous colorectal hybrid ESD studies have involved single institutions or few operators over a short timeframe, and the size for indication has not been established. In this multicentre study, we investigated the clinical outcomes of hybrid ESD for colorectal tumors that met the 30 mm lesion size criterion. METHODS: From January 2008 to December 2018, colorectal hybrid ESD was performed for 172 lesions (diameter range, ≥ 20- < 30 mm) at Hiroshima GI Endoscopy Research Group. We compared clinicopathological characteristics and outcomes between 56 and 116 lesions in planned and salvage groups, respectively. We also compared data between 2008 and 2013 (the first period) and 2014 and 2018 (the second period) to assess operator experience. RESULTS: No significant difference was found in the complete en bloc resection rate between the planned and salvage groups (92.9% vs. 83.6%, respectively). Procedure time was shorter in the planned group (44.5 min) than in the salvage group (72.0 min, p < 0.01). The perforation rate was higher in the salvage group (21.6%) than in the planned group (0%, p < 0.01); however, the perforation rate during snaring in the salvage group was 1.8%. During the second period relative to the first period, we recorded a significantly higher complete en bloc resection rate (95.7% vs. 75.6%, respectively, p < 0.01) and experienced operator rate (75.5% vs. 53.9%, respectively, p < 0.01). Furthermore, no significant difference was found in the complete en bloc resection rate between the planned and salvage groups during the second period (100% vs. 94.4%, respectively). CONCLUSION: Colorectal hybrid ESD, especially salvage hybrid ESD performed by experienced operators, is adoptable and safe for lesions with diameters ranging from ≥ 20 to < 30 mm.

BRAF Mutation Is Associated with Hyperplastic Polyp-Associated Gastric Cancer.

Gastric hyperplastic polyps (GHP) are frequently found to be benign polyps and have been considered to have a low carcinogenic potential. The characteristics of the hyperplastic polyp-associated gastric cancer (HPAGC) remain unclear. Therefore, we analyzed samples from 102 GHP patients and identified 20 low-grade atypical GHPs (19.6%), 7 high-grade atypical GHPs (6.9%), and 5 intramucosal cancer samples (4.9%). GHP atypia was more common in the elderly and increased with increasing polyp size. In particular, polyps larger than 1 cm were associated with a higher grade and cancer. Furthermore, mucus production decreased with increasing atypia. Although no correlation was found between atypia and Helicobacter pylori infection or intestinal metaplasia, enhanced proliferative ability (Ki-67) did correlate with atypia, as did nuclear 8-hydroxy-2'-deoxyguanosine levels. Interestingly, 4-hydroxynonenal levels in granulation tissue and the area ratio of granulation tissue within polyps also correlated with GHP atypia. In five cases of HPAGC, three cases exhibited caudal type homeobox transcription factor (CDX2)-positive cells and a mixed mucin phenotype, which is considered to be related to H. pylori infection. By contrast, two cases were CDX2 negative, with a gastric mucin phenotype, and H. pylori infection was not observed in the tumor or the surrounding mucosa. In these cases, a v-raf murine sarcoma viral oncogene homolog B1 (BRAF) mutation (V600E) was detected. All cancer samples showed high stemness and p53 protein accumulation, but no KRAS mutations. The molecular and phenotypic characteristics of the cases characterized by BRAF mutations may represent a novel subtype of HPAGC, reflecting a conserved pathway to oncogenesis that does not involve H. pylori infection. These findings are worthy of further investigation in a large-scale study with a substantial cohort of HPAGC patients to establish their clinical significance.

Salvage endoscopic submucosal dissection for local residual/recurrent colorectal tumor after endoscopic resection: Large multicenter 10-year study.

OBJECTIVES: For local residual/recurrent and endoscopic resection (ER) interrupted colorectal tumors, endoscopic retreatment is often difficult due to severe submucosal fibrosis. Endoscopic submucosal dissection (ESD) can achieve en bloc resection, even for tumors with severe submucosal fibrosis, although it is a risk factor for incomplete resection and perforation. We aimed to determine the safety and efficacy of colorectal ESD for local residual/recurrent tumors including ER interrupted tumors from a large multicenter study. METHODS: From January 2008 until December 2018, 3,937 colorectal tumors were resected by ESD at the Hiroshima GI Endoscopy Research Group. From this group, 81 local residual/recurrent tumors and 21 ER interrupted tumors were included. We analyzed ESD outcomes, particularly the difference between the early and late phases and re-recurrence after ESD for local residual/recurrent tumors. RESULTS: For local residual/recurrent tumors, en bloc and R0 resection rates were 95% (77/81) and 90% (73/81), respectively. The intraoperative perforation rate was 6% (5/81), and one patient required surgery. The delayed perforation rate was 2% (2/81), and one patient required surgery. For ER interrupted tumors, both the en bloc and R0 resection rates were 86% (18/21), with no major adverse events. For local residual/recurrent and ER interrupted tumors, the intraoperative perforation rate was significantly lower in the late phase compared with the early phase. Following curative resection for local residual/recurrent tumors, no local re-recurrences occurred. CONCLUSIONS: Colorectal ESD is an effective treatment for local residual/recurrent and ER interrupted tumors.

Visualization of a chorus structure in multiple frog species by a sound discrimination device.

We developed a sound discrimination device to identify and localize the species of nocturnal animals in their natural habitat. The sound discrimination device is equipped with a microphone, a light-emitting diode, and a band-pass filter. By tuning the center frequency of the filter to include a dominant frequency of the calls of a focal species, we enable the device to be illuminated only when detecting the calls of the focal species. In experiments in a laboratory room, we tuned the sound discrimination devices to detect the calls of Hyla japonica or Rhacophorus schlegelii and broadcast the frog calls from loudspeakers. By analyzing the illumination pattern of the devices, we successfully identified and localized the two kinds of sound sources. Next, we placed the sound discrimination devices in a field site where actual male frogs (H. japonica and R. schlegelii) produced sounds. The analysis of the illumination pattern demonstrates the efficacy of the developed devices in a natural environment and also enables us to extract pairs of male frogs that significantly overlapped or alternated their calls.

Clinical outcomes of endoscopic resection for superficial non-ampullary duodenal tumors.

Background and study aims Because superficial non-ampullary duodenal epithelial tumors (SNADETs) are relatively rare, studies evaluating the outcomes of endoscopic resection (ER) for SNADETs are limited. Therefore, this study aimed to evaluate the clinical validity of ER for SNADETs. Patients and methods The study participants included 163 consecutive patients (108 men; mean age, 61.5 ±â€Š11.3 years) with 171 SNADETs, excluding patients with familial adenomatous polyposis resected by ER, at Hiroshima University Hospital between May 2005 and September 2016. Clinicopathological features and the outcomes of ER for 171 cases were retrospectively analyzed. Additionally, the prognosis of 135 patients with more than 12 months' follow-up was analyzed. Results Mean diameter of SNADETs was 10.7 ±â€Š7.2 mm. Most of the SNADET cases were classified as category 3 (71 %, 121/171), but some were category 5 (2 %, 3/171). En bloc resection rates were 93 % (146/157), 100 % (7/7), and 86 % (6/7) in endoscopic mucosal resection (EMR), polypectomy, and in endoscopic submucosal dissection (ESD) cases, respectively. Complete resection rates were 90 % (141/157), 100 % (7/7), and 71 % (5/7) in EMR, polypectomy, and ESD cases, respectively. Emergency surgery was performed in two patients with intraoperative perforation and in two with delayed perforation without artificial ulcer bed closure after ER. Since endoscopic closure of ulcer by clipping was performed, delayed perforation has not occurred. Local recurrence occurred in 1.2 %, but no metastasis to lymph nodes or other organs occurred after ER. No patient died of primary SNADETs. Conclusion Our data supported the clinical validity of ER for SNADETs. However, delayed perforation should be given much attention.

Construction of a risk model for the development of metachronous squamous cell carcinoma after endoscopic resection of esopahageal squamous cell carcinoma.

BACKGROUND: Previously, we identified that rs1229984 in ADH1B, rs671 in ALDH2, and smoking status were independently associated with the risk of developing metachronous squamous cell carcinoma (SCC) after endoscopic resection (ER) for esophageal SCC (ESCC). However, this analysis included cases with short-term follow-up. In the present study, we investigated the environmental and genetic factors associated with developing metachronous SCC using long-term follow-up observation after ER for ESCC. METHODS: One hundred and thirty ESCC patients who underwent treatment with ER were followed up using endoscopy for ≥ 30 months. We investigated the incidence of, and genetic/environmental factors associated with, metachronous SCC development after ER for ESCC. We also analyzed the potential risk factors for multiple metachronous SCC development using Cox's proportional hazards model. Moreover, we constructed a risk model for the development of metachronous SCC after ER for ESCC. RESULTS: Male, rs1229984, rs671, alcohol consumption (> 20 g/day), smoking, and multiple Lugol-voiding lesions (LVLs) significantly affected the incidence of multiple metachronous SCCs. Multiple Cox proportional analysis revealed that rs1229984, rs671, alcohol consumption, smoking, and multiple LVLs were independently associated with the risk of developing metachronous SCC. Patients who had ≤ 2 risk factors did not develop metachronous SCC, and the risk of developing metachronous SCC in patients with ≥ 3 risk factors was significantly higher than in patients with ≤ 2 risk factors. CONCLUSION: The risk model using these 5 genetic and environmental factors is useful as an indication for multiple metachronous development in ESCC patients.

Use of anticoagulants increases risk of bleeding after colorectal endoscopic submucosal dissection.

BACKGROUND AND STUDY AIMS: Japanese guidelines for gastroenterological endoscopy have recommended temporary withdrawal of anticoagulants (warfarin, direct oral anticoagulants [DOAC], or heparin) to prevent hemorrhagic complications during endoscopic submucosal dissection (ESD) for colorectal neoplasias (CRNs). However, serious thrombosis might occur during temporary withdrawal of anticoagulants. The current study aimed to evaluate outcomes with anticoagulants in patients undergoing ESD for CRNs. PATIENTS AND METHODS: This study was a single-institution retrospective cohort study based on clinical records. We assessed 650 consecutive patients with 698 CRNs who underwent ESD at Hiroshima University Hospital between December 2010 and June 2016. The patients were divided into three groups: the warfarin group (19 patients with 19 CRNs), DOAC group (7 patients with 9 CRNs), and no-antithrombotics group (624 patients with 670 CRNs). We replaced warfarin with heparin 3 to 5 days before endoscopy. Although DOAC was suspended on the morning of endoscopy, we did not replace heparin. RESULTS: Bleeding after the procedure occurred in 26.3 % (5/19), 22.0 % (2/9), and 2.7 % (18/670) of patients in the warfarin, DOAC, and no-antithrombotics groups, respectively. In the warfarin group, four patients who bled after the procedure took not only warfarin but also other antiplatelets. En bloc resection rates were 94.7 % (18/19), 100 % (9/9), and 96.6 % (647/670) in the warfarin, DOAC, and no-antithrombotics groups, respectively. No patients experienced ischemic events in the perioperative period. CONCLUSIONS: Among patients undergoing ESD for CRNs, risk of bleeding was higher among patients who took anticoagulants than among those who did not. In particular, careful attention to patients who took antiplatelets in addition to warfarin before ESD for CRNs is warranted.

Magnifying Endoscopy with Narrow Band Imaging in Estimating the Invasion Depth of Superficial Esophageal Squamous Cell Carcinomas.

BACKGROUND/AIM: The aim of this study was to compare the accuracy of magnifying endoscopy with narrow band imaging for the diagnosis of depth of invasion by Japan Esophageal Society (JES) classification and inter- and intraobserver agreement of JES intrapapillary capillary loop (IPCL) classification. METHODS: It was a retrospective observational study that has analyzed 136 patients with esophageal malignant neoplasia with magnifying endoscopy narrow band imaging to compare JES's IPCL classification to the histopathologic findings and to evaluate the inter- and intraobserver agreement. RESULTS: Histopathologic examinations revealed 34 (25.7%) intraepithelial neoplasias, 70 (51.5%) squamous cell carcinomas (SCCs) in the epithelium or with invasion into the lamina propria mucosa, 21 (15.4%) SCCs with invasion into the muscularis mucosa or mild invasion into the submucosa, and 11 (8.1%) SCCs with moderate or deep invasion into the submucosa. IPCL types B1, B2, and B3 also showed high accuracies of 80.8, 83.1, and 94.1%, respectively. The kappa values for inter- and intraobserver agreements of the IPCL classifications were moderate to almost perfect. CONCLUSIONS: In the present study, the JES's IPCL classification has good accuracy to predict the depth of SCC invasion and moderate to almost perfect intra- and interobserver agreements.

Taking Warfarin with Heparin Replacement and Direct Oral Anticoagulant Is a Risk Factor for Bleeding after Endoscopic Submucosal Dissection for Early Gastric Cancer.

BACKGROUND: Although bleeding after endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) remains problematic, especially in patients taking anticoagulants, there are differing views on the ideal and optimal management for these patients. This study investigated the risk of bleeding after ESD in patients taking anticoagulants. METHODS: We enrolled 61 consecutive patients taking anticoagulants (anticoagulant group) and 968 patients taking no antithrombotic agents (non-antithrombotic group) treated with ESD for EGC between December 2010 and October 2016. We analyzed the risk factors for bleeding after ESD in relation to the various clinical factors. RESULTS: Incidences of bleeding after ESD were significantly higher (14%; 11/76) in the anticoagulant group compared to the non-antithrombotic group (3%; 40/1,167). Moreover, bleeding after ESD was significantly more common in patients in the warfarin monotherapy group (14%; 5/37) and in the direct oral anticoagulant (DOAC) monotherapy group (22%; 4/18), compared to the non-antithrombotic group. Multivariate analysis revealed that dialysis, the use of anticoagulants, and an operation time ≥75 min were independent risk factors for bleeding after ESD. CONCLUSIONS: Our data suggest that patients who take warfarin and receive heparin bridging, and those who take DOAC medication, are prone to bleeding after ESD for EGC.

Evaluation of the visibility of early gastric cancer using linked color imaging and blue laser imaging.

BACKGROUND: Blue laser imaging (BLI) and linked color imaging (LCI) are the color enhancement features of the LASEREO endoscopic system, which provide a narrow band light observation function and expansion and reduction of the color information, respectively. METHODS: We examined 82 patients with early gastric cancer (EGC) diagnosed between April 2014 and August 2015. Five expert and 5 non-expert endoscopists retrospectively compared images obtained on non-magnifying BLI bright mode (BLI-BRT) and LCI with those obtained via conventional white light imaging (WLI). Interobserver agreement was also assessed. RESULTS: In experts' evaluation of the images, an improvement in visibility was observed in 73% (60/82) and 20% (16/82) of cases under LCI and BLI-BRT, respectively. In non-experts' evaluation of the images, an improvement in visibility was observed in 76.8% (63/82) and 24.3% (20/82) of cases under LCI and BLI-BRT, respectively. There were no significant differences between experts and non-experts in the evaluation of the images. The improvement in visibility was significantly higher with LCI than with BLI-BRT in experts and non-experts (p < 0.01). With regard to tumor color on WLI, the improvement in the visibility of reddish and whitish tumors was significantly higher than that of isochromatic tumors when LCI was used. The improvement in visibility with LCI was observed in 71% (12/17) and 74% (48/65) of patients with and without Helicobacter pylori (Hp) eradication, respectively; no significant difference in improvement was observed between these groups. The interobserver agreement was good to satisfactory at ≥ 0.62. CONCLUSIONS: In conclusion, our study showed that LCI improved the visibility of EGC, regardless of the level of endoscopists' experience or Hp eradication in patients, particularly for EGCs with a reddish or whitish color. The improvement in visibility was significantly higher with LCI than that with BLI.

Visualizing Phonotactic Behavior of Female Frogs in Darkness.

Many animals use sounds produced by conspecifics for mate identification. Female insects and anuran amphibians, for instance, use acoustic cues to localize, orient toward and approach conspecific males prior to mating. Here we present a novel technique that utilizes multiple, distributed sound-indication devices and a miniature LED backpack to visualize and record the nocturnal phonotactic approach of females of the Australian orange-eyed tree frog (Litoria chloris) both in a laboratory arena and in the animal's natural habitat. Continuous high-definition digital recording of the LED coordinates provides automatic tracking of the female's position, and the illumination patterns of the sound-indication devices allow us to discriminate multiple sound sources including loudspeakers broadcasting calls as well as calls emitted by individual male frogs. This innovative methodology is widely applicable for the study of phonotaxis and spatial structures of acoustically communicating nocturnal animals.