• Korean Journal of Optics and Photonics
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• v.33 no.6
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• pp.295-302
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• 2022

In this paper, a wedge prism application method was studied to design a full-high-definition (FHD)-class high-resolution flexible endoscope. In the case of the conventional flexible endoscope optical system, the F number is made large or a liquid lens is applied to obtain the same imaging performance in a wide depth of field. However, there is a problem in that the diameter of the optical system increases because an additional light guide and equipment are required. To solve this problem, two wedge prisms were applied to the flexible endoscope optical system to adjust the image distance for each object distance. First, two wedge prisms were symmetrically placed on the designed endoscopic optical system. An image distance satisfying the target imaging performance according to each objective distance was derived. Next, the wedge prism decenter value for controlling the image distance was derived. By combining these two data, a wedge prism decenter value that satisfied the target imaging performance at each object distance was applied in multi configurations. As a result of the optimal design applied with the wedge prism, a target imaging performance of more than 20% of the modulation transfer function for a resolution of 178 cycles/mm was satisfied in the entire depth of field of 100 mm-7 mm.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.24 no.4
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• pp.357-365
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• 2021

Purpose: A change in diagnosis from ulcerative colitis (UC) to Crohn's disease (CD) has been reported in pediatric inflammatory bowel disease; however, only a few clinical characteristics and predictors of this diagnostic change have been reported. We aimed to describe the clinical characteristics of patients with UC who underwent a change in diagnosis to CD and identify variables associated with the change. Methods: The medical records of pediatric patients with UC who were followed up at the National Center for Child Health and Development between 2006 and 2019 were retrospectively reviewed. Clinical data on disease phenotype, laboratory parameters, endoscopic findings, and treatment of patients whose diagnosis changed to CD (cCD) were compared to those of patients whose diagnosis remained UC (rUC). Results: Among the 111 patients initially diagnosed with UC, 11 (9.9%) patients were subsequently diagnosed with CD during follow-up. There was no significant difference between the cCD and rUC groups in terms of sex, age at initial diagnosis, and the extent and severity of disease at initial diagnosis. Albumin and hemoglobin levels were significantly lower in the cCD group than in the rUC group. The proportion of patients who required biologics was significantly higher in the cCD group than in the rUC group (p<0.05). Conclusion: Approximately 10% children initially diagnosed with UC were subsequently diagnosed with CD. Hypoalbuminemia and anemia at initial diagnosis and use of biologics could be predictors of this diagnostic change.

• Journal of Gastric Cancer
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• v.22 no.3
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• pp.184-196
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• 2022

Purpose: Total or proximal gastrectomy of the upper-third early gastric cancer (u-EGC) often causes severe post-gastrectomy syndrome, suggesting that these procedures are extremely invasive for patients without pathologically positive lymph node (LN) metastasis. This study aimed to evaluate the clinical applicability of a stomach function-preserving surgery, local resection (LR), with prophylactic left gastric artery (LGA)-basin dissection (LGA-BD). Materials and Methods: The data of patients with u-EGC (pathologically diagnosed as T1) were retrospectively analyzed. Total gastrectomy was performed in 30 patients, proximal gastrectomy in 45, and subtotal gastrectomy in 6; the LN status was evaluated assuming that the patients had already underwent LR + LGA-BD. This procedure was considered feasible in patients without LN metastases or in patients with cancer in the LGA basin. The reproducibility of the results was also evaluated using an external validation dataset. Results: Of the 82 eligible patients, 79 (96.3%) were cured after undergoing LR + LGA-BD, 74 (90.2%) were pathologically negative for LN metastases, and 5 (6.1%) had LN metastases, but these findings were only observed in the LGA basin. Similarly, of the 406 eligible tumors in the validation dataset, 396 (97.5%) were potentially curative. Tumors in the lesser curvature, post-endoscopic resection status, and small tumors (<20 mm) were considered to be stronger indicators of LR + LGA-BD as all subpopulation cases met our feasibility criteria. Conclusions: More than 95% of the patients with u-EGC might be eligible for LR + LGA-BD. This function-preserving procedure may contribute to the development of u-EGC without pathological LN metastases, especially for tumors located at the lesser curvature.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.25 no.3
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• pp.218-227
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• 2022

Purpose: To analyze the characteristics of pediatric inflammatory bowel disease (IBD) over the past three decades in Argentina and determine if there are differences between the first two decades and the past decade. Methods: We conducted a retrospective multicenter analytical study in children with IBD between 0 and 18 years of age diagnosed between 1987 and 2017 in three tertiary health centers in Argentina. The evaluation included clinical characterization, endoscopy, histology, and imaging data together with therapeutic strategies. The patients were divided into two groups: Group 1, diagnosed between 1987 and 2007, and Group 2, diagnosed between 2008 and 2017. Results: Of the 756 patients included, 409 (54%) had ulcerative colitis (UC), 250 (33%) had Crohn's disease (CD), and 97 (13%) had IBD-unclassified (IBD-U). The positive family history was 3.8%, which was more frequent among children under two years of age (6.7%). There were no significant differences in clinical presentation and extraintestinal manifestations between periods, with hepatic manifestations being the most frequent. In the last decade, we found an upward trend in CD, a downward trend in UC/IBD-U, even after adjustment for socioeconomic status, and a decrease of 50% in surgical treatments coinciding with the advent of biological therapy. Conclusion: This is the first multicenter cohort study in a Latin American country to describe clinical, endoscopic, and therapeutic data across the past 30-year period. Although CD was responsible for the overall increase in incidence, UC was still prevalent in this region.

• Journal of Gastric Cancer
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• v.23 no.1
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• pp.107-145
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• 2023

The first edition of 'A Standardized Pathology Report for Gastric Cancer' was initiated by the Gastrointestinal Pathology Study Group of the Korean Society of Pathologists and published 17 years ago. Since then, significant advances have been made in the pathologic diagnosis, molecular genetics, and management of gastric cancer (GC). To reflect those changes, a committee for publishing a second edition of the report was formed within the Gastrointestinal Pathology Study Group of the Korean Society of Pathologists. This second edition consists of two parts: standard data elements and conditional data elements. The standard data elements contain the basic pathologic findings and items necessary to predict the prognosis of GC patients, and they are adequate for routine surgical pathology service. Other diagnostic and prognostic factors relevant to adjuvant therapy, including molecular biomarkers, are classified as conditional data elements to allow each pathologist to selectively choose items appropriate to the environment in their institution. We trust that the standardized pathology report will be helpful for GC diagnosis and facilitate large-scale multidisciplinary collaborative studies.

• Journal of Gastric Cancer
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• v.23 no.2
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• pp.355-364
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• 2023

Background: There are no clear guidelines to determine whether to perform D1 or D1+ lymph node dissection in early gastric cancer (EGC). This study aimed to develop a nomogram for estimating the risk of extraperigastric lymph node metastasis (LNM). Materials and Methods: Between 2009 and 2019, a total of 4,482 patients with pathologically confirmed T1 disease at 6 affiliated hospitals were included in this study. The basic clinicopathological characteristics of the positive and negative extraperigastric LNM groups were compared. The possible risk factors were evaluated using univariate and multivariate analyses. Based on these results, a risk prediction model was developed. A nomogram predicting extraperigastric LNM was used for internal validation. Results: Multivariate analyses showed that tumor size (cut-off value 3.0 cm, odds ratio [OR]=1.886, P=0.030), tumor depth (OR=1.853 for tumors with sm2 and sm3 invasion, P=0.010), cross-sectional location (OR=0.490 for tumors located on the greater curvature, P=0.0303), differentiation (OR=0.584 for differentiated tumors, P=0.0070), and lymphovascular invasion (OR=11.125, P<0.001) are possible risk factors for extraperigastric LNM. An equation for estimating the risk of extraperigastric LNM was derived from these risk factors. The equation was internally validated by comparing the actual metastatic rate with the predicted rate, which showed good agreement. Conclusions: A nomogram for estimating the risk of extraperigastric LNM in EGC was successfully developed. Although there are some limitations to applying this model because it was developed based on pathological data, it can be optimally adapted for patients who require curative gastrectomy after endoscopic submucosal dissection.

• Journal of Digestive Cancer Reports
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• v.7 no.1
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• pp.22-25
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• 2019

A 58-year-old woman presented with right flank and back pain for one month. After undergoing an abdominal computed tomography (CT), she was referred to our hospital. The abdominal CT showed a hypodense pancreatic tail mass with multiple retroperitoneal lymph node metastases. Positron emission tomography-computed tomography (PET-CT) scan showed high 18F-FDG uptake in pancreatic tumor and enlarged lymph nodes. Endoscopic ultrasound fine needle aspiration (EUS-FNA) revealed adenocarcinoma, which stained strongly in hENT1 (human equilibrative nucleoside transporter 1) on immunohistochemistry. She received gemcitabine 1,000 mg/m² + nanoparticle albumin-bound paclitaxel 125 mg/m² as a palliative chemotherapy. Follow-up abdominal CT and PET-CT after 4 cycles of chemotherapy showed that both pancreatic mass and the metastatic retroperitoneal lymph nodes were nearly disappeared. We report a case of 58-year-old female with metastatic pancreatic cancer who had a dramatic response to palliative chemotherapy (gemcitabine plus nanoparticle albumin-bound paclitaxel).

• Journal of Digestive Cancer Research
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• v.5 no.2
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• pp.125-129
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• 2017

A 38-year-old man presented with abdominal discomfort and was diagnosed as type 3 advanced gastric cancer with multiple liver and lung metastases (Stage IV). Endoscopic forcep biopsy revealed moderately differentiated adenocarcinoma, which stained positive HER2 (Human epidermal growth factor receptor) on immunohistochemistry. We started chemotherapy with FP (5-Fluorouracil plus Cisplatin) plus trastuzumab. After 6 cycles of FP plus trastuzumab chemotherapy, there were partial response in the liver, lung and lymph nodes metastasis. Especially, metastatic lung lesions showed remarkable improvement. Chemotherapy with FP plus trastuzamab was effective for HER2 positive advanced cancer with multiple liver and lung metastases. Through active research on target therapy about advanced gastric cancer, we expect to improve the survival rate and quality of life of patients with advanced gastric cancer who can not undergo curative resection.

• Korean Journal of Radiology
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• v.22 no.10
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• pp.1640-1649
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• 2021

Objective: Flattening in the anteroposterior direction (AP flattening) of the terminal ileum (TI) or sigmoid colon (SC) lying across the psoas muscle, on magnetic resonance enterography (MRE), might mimic bowel inflammation in the coronal view. This study investigated the prevalence of AP flattening and the factors associated with its development. Materials and Methods: A total of 364 surgery-naïve patients with Crohn's disease (CD) who had undergone MRE were retrospectively reviewed. AP flattening was defined as a luminal collapse in the anteroposterior direction, with a bowel width in the axial plane < 1/4 of the normal diameter without reduction of bowel width in coronal images. The prevalence of AP flattening of the TI and SC on MRE in patients with bowel segments lying across the psoas muscle was determined. We further compared the rate of AP flattening between MRE and computed tomography enterography (CTE) in a subcohort of patients with prior CTE. The factors associated with AP flattening were analyzed using multivariable logistic regression in a subcohort of patients with endoscopic findings of TI. Results: Three hundred and twenty-two and 363 patients, respectively, had TI and SC lying across the psoas muscle. The prevalence of AP flattening on MRE was 7.5% (24/322) in TI and 5.2% (19/363) in SC. The prevalences were significantly higher on MRE than on CTE in both the TI (7.3% [12/164] vs. 0.6% [1/164]; p = 0.003) and SC (5.8% [11/190] vs. 1.6% [3/190]; p = 0.039). AP flattening of the TI was independently and strongly associated with the absence of CD inflammation on endoscopy, with an adjusted odds ratio of 0.066 (p = 0.003) for the presence versus the absence (reference) of inflammation. Conclusion: AP flattening of the TI or SC lying across the psoas muscle was uncommon and predominantly observed on MRE of the bowel without CD inflammation.

• Annals of Hepato-Biliary-Pancreatic Surgery
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• v.27 no.4
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• pp.350-365
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• 2023

Backgrounds/Aims: Extra hepatic portal venous obstruction (EHPVO) is the most common cause of portal hypertension in Indian children. While endoscopy is the primary modality of management, a subset of patients require surgery. This study aims to report the short- and long-term outcomes of EHPVO patients managed surgically. Methods: All the patients with EHPVO who underwent surgery between August 2007 and December 2021 were retrospectively reviewed. Postoperative complications were classified after Clavien-Dindo. Binary logistic regression in Wald methodology was used to determine the predictive factors responsible for unfavourable outcome. Results: Total of 202 patients with EHPVO were operated. Mean age of patients was 20.30 ± 9.96 years, and duration of illness, 90.05 ± 75.13 months. Most common indication for surgery was portal biliopathy (n = 59, 29.2%), followed by bleeding (n = 50, 24.8%). Total of 166 patients (82.2%) had shunt procedure. Splenectomy with esophagogastric devascularization was the second most common surgery (n = 20, 9.9%). Nine major postoperative complications (Clavien-Dindo > 3) were observed in 8 patients (4.0%), including 1 (0.5%) operative death. After a median follow-up of 56 months (15-156 months), 166 patients (82.2%) had favourable outcome. In multivariate analysis, associated splenic artery aneurysm (p = 0.007), isolated gastric varices (p = 0.004), preoperative endoscopic retrograde cholangiography and stenting (p = 0.015), and shunt occlusion (p < 0.001) were independent predictors of unfavourable long-term outcome. Conclusions: Surgery in EHPVO is safe, affords excellent short- and long-term outcome in patients with symptomatic EHPVO, and may be considered for secondary prophylaxis.