Favorable Prognostic Factors for Survival Outcomes of Hepatocellular Carcinoma with Portal Vein Tumor Thrombosis After Hepatectomy.

BACKGROUND: This study aimed to investigate prognostic factors of recurrence and survival associated with hepatocellular carcinoma (HCC) with portal vein tumor thrombosis (PVTT). PATIENTS AND METHODS: This retrospective study included 161 patients with HCC with PVTT who underwent hepatectomy between January 2003 and January 2014 at the Asan Medical Center. Regression analyses were conducted to identify favorable predictive factors for overall survival (OS) and recurrence-free survival (RFS). RESULTS: The median follow-up was 15.9 months, while 1-, 3-, and 5-year OS was 65.0%, 38.4%, and 36.0%, respectively, and 1-year RFS was 25.5%. There were no significant differences in OS and RFS between the patients with portal vein invasion (Vp) 1-2 and Vp3-4 PVTT. Patients with intrahepatic recurrence had significantly better overall survival than patients with extrahepatic recurrence. Transcatheter arterial chemoembolization and radiofrequency ablation were the most effective treatments for intrahepatic metastasis, and surgery was the most effective treatment for extrahepatic metastasis. On multivariate analysis, absence of esophageal varices, maximal tumor size < 5 cm, tumor location in single lobe, and anatomical resection were favorable prognostic factors for OS and R0 resection, and absence of microvascular invasion was a favorable prognostic factor for RFS. CONCLUSION: The long-term outcome of patients with HCC with PVTT can be improved under consideration of favorable prognostic factors including absence of esophageal varices, maximal tumor size < 5 cm, tumor location in single lobe, and anatomical resection, R0 resection, and absence of microvascular invasion. In addition, recurrent HCC required aggressive management to prolong overall survival.

Machine learning-based survival rate prediction of Korean hepatocellular carcinoma patients using multi-center data.

AIM: To predict survival time of Korean hepatocellular carcinoma (HCC) patients using multi-center data as a foundation for the development of a predictive artificial intelligence model according to treatment methods based on machine learning. METHODS: Data of patients who underwent treatment for HCC from 2008 to 2015 was provided by Korean Liver Cancer Study Group and Korea Central Cancer Registry. A total of 10,742 patients with HCC were divided into two groups, with Group I (2920 patients) confirmed on biopsy and Group II (5562 patients) diagnosed as HCC according to HCC diagnostic criteria as outlined in Korean Liver Cancer Association guidelines. The data were modeled according to features of patient clinical characteristics. Features effective in predicting survival rate were analyzed retrospectively. Various machine learning methods were used. RESULTS: Target was overall survival time, which divided into approximately 60 months (= /< 60 m, > 60 m). Target distribution in Group I (total 514 samples) was 28.8%: (148 samples) less than 60 months, 71.2% (366 samples) greater than 60 months, and in Group II (total 757 samples) was 66.6% (504 samples) less than 60 months, 33.4% (253 samples) greater than 60 months. Using NG Boost method, its accuracy was 83%, precision 84%, sensitivity 95%, and F1 score 89% for more than 60 months survival time in Group I with surgical resection. Moreover, its accuracy was 79%, precision 82%, sensitivity 87%, and F1 score 84% for less than 60 months survival time in Group II with TACE. The feature importance with gain criterion indicated that pathology, portal vein invasion, surgery, metastasis, and needle biopsy features could be explained as important factors for prediction in case of biopsy (Group I). CONCLUSION: By developing a predictive model using machine learning algorithms to predict prognosis of HCC patients, it is possible to project optimized treatment by case according to liver function and tumor status.

Prognostic Impact of Resection Margin Length in Patients Undergoing Resection for Mid-Common Bile Duct Cancer: A Single-Center Experience.

INTRODUCTION: The purpose of this study was to analyze survival outcomes after segmental bile duct resection (BDR) for mid-common bile duct cancer according to the length of the tumor-free BDR margins. METHOD: A total of 133 consecutive patients underwent BDR for mid-bile duct cancers between December 2007 and June 2017. The Cox proportional hazard model was used to verify the cutoff value of the R0 resection margin. The patients were divided into 3 groups according to resection margin status (group 1; R0 resection margin ≥5 mm; group 2, R0 resection margin <5 mm; and group 3, R1 resection margin). RESULTS: The median follow-up period of the study cohort was 24 months. A resection margin of 5 mm in length was verified to be suitable as a reliable cutoff value. The median disease-free and overall survival (OS) periods were 32 and 49 months in group 1, 13 and 20 months in group 2, and 23 and 30 months in group 3, respectively (p = 0.03 and p < 0.001). The length of the tumor-free resection margin (hazard ratio, 2.01; 95% confidence interval, 1.10-3.67; p = 0.022) was independent factor affecting OS. CONCLUSIONS: BDR for mid-bile duct cancer appears to be a feasible surgical option in selected patients with careful preoperative imaging assessment and intraoperative frozen-section diagnosis. Our results suggest achieving a BDR margin ≥5 mm to improve survival outcomes.

Hepatitis B Prophylaxis after Liver Transplantation in Korea: Analysis of the KOTRY Database.

BACKGROUND: Prophylaxis for hepatitis B virus (HBV) recurrence is essential after liver transplantation (LT) in HBV-associated recipients. We conducted real-world analysis of HBV prophylaxis after LT in the Korean population. METHODS: Korean Organ Transplantation Registry (KOTRY) database and additionally collected data (n = 326) were analyzed with special reference to types of HBV prophylaxis. RESULTS: The study cohort comprised 267 cases of living-donor LT and 59 cases of deceased-donor LT. Hepatocellular carcinoma (HCC) was diagnosed in 232 (71.2%) of these subjects. Antiviral agents were used in 255 patients (78.2%) prior to LT. HBV DNA was undetectable in 69 cases (21.2%) and detectable over wide concentrations in the other 257 patients (78.8%) prior to LT. Polymerase chain reaction analysis of the store blood samples detected HBV DNA in all patients, with 159 patients (48.9%) showing concentrations > 100 IU/mL. Post-transplant HBV regimens during the first year included combination therapy in 196 (60.1%), hepatitis B immunoglobulin (HBIG) monotherapy in 121 (37.1%), and antiviral monotherapy in 9 (2.8%). In the second post-transplant year, these regimens had changed to combination therapy in 187 (57.4%), HBIG monotherapy in 112 (34.4%), and antiviral monotherapy in 27 (8.3%). Trough antibody to hepatitis B surface antigen titers > 500 IU/mL and >1,000 IU/mL were observed in 61.7% and 25.2%, respectively. The mean simulative half-life of HBIG was 21.6 ± 4.3 days with a median 17.7 days. Up to 2-year follow-up period, HCC recurrence and HBV recurrence developed in 18 (5.5%) and 6 (1.8%), respectively. HCC recurrence developed in 3 of 6 patients with HBV recurrence. CONCLUSION: Combination therapy is the mainstay of HBV prophylaxis protocols in a majority of Korean LT centers, but HBIG was often administered excessively. Individualized optimization of HBIG treatments using SHL is necessary to adjust the HBIG infusion interval.

Validation of the prognostic performance in various nodal staging systems for gallbladder cancer: results of a multicenter study.

BACKGROUND: Although the current nodal staging system for gallbladder cancer (GBC) was changed based on the number of positive lymph nodes (PLN), it needs to be evaluated in various situations. METHODS: We reviewed the clinical data for 398 patients with resected GBC and compared nodal staging systems based on the number of PLNs, the positive/retrieved LN ratio (LNR), and the log odds of positive LN (LODDS). Prognostic performance was evaluated using the C-index. RESULTS: Subgroups were formed on the basis of an restricted cubic spline plot as follows: PLN 3 (PLN = 0, 1-2, ≥ 3); PLN 4 (PLN = 0, 1-3, ≥ 4); LNR (LNR = 0, 0-0.269, ≥ 0.27); and LODDS (LODDS < - 0.8, - 0.8-0, ≥ 0). The oncological outcome differed significantly between subgroups in each system. In all patients with GBC, PLN 4 (C-index 0.730) and PLN 3 (C-index 0.734) were the best prognostic discriminators of survival and recurrence, respectively. However, for retrieved LN (RLN) ≥ 6, LODDS was the best discriminator for survival (C-index 0.852). CONCLUSION: The nodal staging system based on PLN was the optimal prognostic discriminator in patients with RLN < 6, whereas the LODDS system is adequate for RLN ≥ 6. The following nodal staging system considers applying different systems according to the RLN.

Prognostic significance of Human epidermal growth factor receptor-2 expression in patients with resectable gastric adenocarcinoma.

BACKGROUND: The purpose of this study was to investigate the correlation between human epidermal growth factor receptor 2 (HER2) overexpression and clinicopathologic factors and overall survival rate in patients who underwent curative gastrectomy for gastric adenocarcinoma. METHODS: Among patients who underwent curative gastrectomy for gastric adenocarcinoma at Inje University Paik Hospital from January 2012 to December 2015, 782 patients underwent an immunohistochemical analysis to evaluate HER2 expression levels. Clinicopathologic records that were collected from a gastric cancer database were retrospectively reviewed to identify clinicopathologic factors and survival rates of the patients. RESULTS: HER2 overexpression was detected in 166 patients (21.2%). There was a statistically significant correlation between HER2 expression level and sex (p = 0.013), histologic differentiation (p < 0.001), Lauren classification (p < 0.001), and T pathologic stage (p = 0.022). There were no statistically significant relationships between HER2 expression level and overall 5-year survival rate (p = 0.775) and overall 5-year survival rate of gastric adenocarcinoma classified according to the TNM stage (stage I: p = 0.756, stage II: p = 0.571, stage III: p = 0.704). The HER2 expression level was not affected by the overall 5-year survival rate in the uni- and multivariate analyses. CONCLUSIONS: In this study, the HER2 overexpression rate in gastric adenocarcinoma was 21.2% and was observed in well- and moderately differentiated types according to histologic differentiation, intestinal type according to the Lauren classification, male, and low T stage. There was no correlation between HER2 expression level and overall 5-year survival rate, and HER2 expression level was not associated with independent prognostic factors.

Restoration of portal flow using a pericholedochal varix in adult living donor liver transplantation for patients with total portosplenomesenteric thrombosis.

In total portosplenomesenteric thrombosis patients, cavoportal hemitransposition (CPHT) is indicated but rarely applicable for adult-to-adult (A-to-A) living donor liver transplantation (LDLT) because partial liver graft requires splanchno-portal inflow for liver graft regeneration. If intra- & peri-pancreatic collaterals draining into pericholedochal varix were present, pericholedochal varix may provide splanchnic blood flow to the transplanted liver and also relieve recipient's portal hypertension. To date, however, there is no successful report using pericholedochal varix in liver transplantation (LT). We successfully performed A-to-A LDLTs using pericholedochal varix for those 2 patients. The surgical strategies are followings: (a) dissection of hepatic hilum to isolate left hepatic artery using for arterial reconstruction of implanted right lobe graft, (b) en-mass clamping of the undissected remaining hilum if we can leave adequate length of stump from the clamping site, and then hilum is divided, (c) delay the donor hepatectomy until the feasibility of the recipient operation is confirmed. Portal flow was established between the sizable pericholedochal varix (caliber > 1cm) and graft portal vein, but the individually designed approaches were used for each patients. Currently, they have been enjoying normal life on posttransplant 92 and 44 months respectively. In conclusion, enlarged pericholedochal varix in patients with totally obliterated splanchnic veins might be an useful inflow to restore portal flow and secure good outcome in A-to-A LDLT. AASLD.

Survival differences between Milan criteria after down-staging and De novo Milan in living donor liver transplantation for hepatocellular carcinoma.

BACKGROUND/AIMS: This study reports our experiences of adult living donor liver transplantation (LDLT) corresponding to downstaging. METHODOLOGY: Between July 1992 and April 2008, we performed 553 adult LDLTs (35.1%, 553/1575) for HCC. Sixty-five patients was not treated before LDLT and belonged to Milan criteria, classified as De novo Milan group (De novo-M); 22 HCC patients did not meet Milan criteria initially, but subsequently met the criteria after downstaging, classified as artificial Milan group (Artificial-M). The evaluation of downstaging was based on preoperative CT scan and explanted liver biopsy, and excluded the patients having unclear treatment history on analysis. RESULTS: Artificial-M showed significantly less Child C patients (25%) than De novo-M (64.5%) (0.037). Artificial-M had greater tumor burden than De novo-M in maximal tumor size (2.5 +/- 1.2 versus 2.2 +/- 0.95 cm), sum of tumor diameter (3.4 +/- 1.4 versus 2.4 +/- 1.0 cm), number of nodules (1.8 +/- 0.9 versus 1.2 +/- 0.5), respectively. Five-year cumulative survival was not different between Artificial-M and De novo-M (83.9% versus 93.9%), but 5-year disease free survival were significantly different (71.1% versus 96.5%) (p = 0.0016). CONCLUSIONS: Five year overall survival rates after LDLT were good in both groups. However, stricter follow-up is necessary in Artificial-M considering greater tumor burden and higher recurrence rate compared to De novo-M.

Surgical outcomes of hepatocellular carcinoma with bile duct tumor thrombus: a Korean multicenter study.

BACKGROUND: The long-term outcomes after resection for hepatocellular carcinoma (HCC) with macroscopic bile duct tumor thrombus (BDTT) are unclear. This multicenter study was conducted to determine the prognosis of HCC patients with macroscopic BDTT who underwent resection with curative intent. METHODS: Of 4,308 patients with HCC from four Korean institutions, this single-arm retrospective study included 73 patients (1.7 %) who underwent resection for HCC with BDTT. RESULTS: Jaundice was also present in 34 patients (46.6 %). According to Ueda classification, BDTT was type 2 in 34 cases (46.6 %) and type 3 in 39 cases (53.4 %). Biliary decompression was performed in 33 patients (45.2 %), decreasing the median lowest bilirubin level to 1.4 mg/dL before surgery. Systematic hepatectomy was performed in 69 patients (94.5 %), and concurrent bile duct resection was performed in 31 patients (42.5 %). Surgical curability types were R0 (n = 57; 78.1 %), R1 (n = 11; 15.1 %), and R2 (n = 5; 6.8 %). Patient survival rates were 76.5 % at 1 year, 41.4 % at 3 years, 32.0 % at 5 years, and 17.0 % at 10 years. Recurrence rates were 42.9 % at 1 year, 70.6 % at 3 years, 77.3 % at 5 years, and 81.1 % at 10 years. Results of univariate survival analysis showed that maximal tumor size, bile duct resection, and surgical curability were significant risk factors for survival, and surgical curability was a significant risk factor for recurrence. Multivariate analysis did not reveal any independent risk factors. CONCLUSIONS: Hepatocellular carcinoma patients with BDTT achieved relatively favorable long-term results after resection; therefore extensive surgery should be recommended when complete resection is anticipated.

Relationship between patterns of calcification in thyroid nodules and histopathologic findings.

Various patterns of calcification have been detected in benign and malignant thyroid nodules on ultrasonography (US). Microcalcification has been found to be highly associated with papillary thyroid carcinoma. However, other patterns of calcification have unclear clinical significance. The aim of this study was to evaluate which pattern of calcification could be predictive of malignancy. A total of 1,431 thyroid nodules of 1,078 patients who received preoperative ultrasound examinations and subsequently underwent thyroidectomy were retrospectively reviewed. The types of calcification were defined as follows: microcalcification, annular-like peripheral calcification, crescent-like peripheral calcification, intranodular coarse calcification, and calcified spot. Of these 1,431 nodules, 1,305 (91.1%) were thyroid carcinomas and 126 (8.9%) were benign nodules. Calcifications were detected in 38.6% (552/1,431) of all nodules. Calcifications were found in 40.2% (524/1,305) of malignant nodules and 22.2% (28/126) of benign nodules. Of the 524 malignant nodules with calcification, microcalcification was the most common pattern, occurring in 42.9% (225/524), and annular type was the least common pattern, occurring in 5.9% (31/524). Among the calcification types, only microcalcification and intranodular had a significant association with malignancy (p = 0.001, 0.035), with OR values of 3.5 (95% CI, 1.6-7.7) and 2.4 (95% CI, 1.1-5.6). Though using the patterns of calcification alone for predicting malignancy had limitation, microcalcification and intranodular calcification were significantly associated with malignancy.

A Case of medullary thyroid carcinoma with de novo V804M RET germline mutation.

Many cases of RET proto-oncogene mutations of hereditary medullary thyroid carcinoma (MTC) have been reported in Korea. However, MTC with V804M RET proto-oncogene germline mutations have not been reported in Korea. A 33-yr-old man was diagnosed with a 0.7-cm sized thyroid nodule. Laboratory testing revealed serum calcitonin was elevated. The patient underwent total thyroidectomy with central compartment neck dissection for the thyroid tumor. RET gene analysis was performed in both the index patient and his family. There were no V804M RET mutation and abnormal laboratory findings within his family except the index patient. Therefore, this patient was a de novo V804M RET germline mutation.

Comparison of severity predictive rules for hospitalised nursing home-acquired pneumonia in Korea: a retrospective observational study.

BACKGROUND: Nursing home-acquired pneumonia (NHAP) is the leading cause of death among long-term care residents. AIMS: To compare current scoring indices (NHAP model score, Pneumonia Severity Index (PSI), CURB-65 (confusion, urea nitrogen, respiratory rate, blood pressure, age >65 years) and SOAR (systolic blood pressure, oxygenation, age, respiratory rate)) in predicting mortality and admission to the intensive care unit (ICU) in patients with NHAP. METHODS: This retrospective observational study was conducted between July 2008 and June 2011 using data from the Korean Nursing Home Networks. Two hundred and eight nursing home residents were hospitalised with pneumonia in one general hospital. The primary outcome measure was 30-day all-cause mortality. Secondary outcome measures were intensive respiratory or vasopressor support (IRVS), and severe pneumonia (ICU admission or IRVS). RESULTS: PSI class V showed the highest Youden index (0.45), specificity (66.7%), positive predictive value (PPV, 40.0%), negative predictive value (NPV, 91.5%), and area under the curve (AUC, 0.73) for 30-day mortality. For severe pneumonia, PSI class V showed the highest Youden index (0.40), specificity (72.8%), PPV (62.2%), NPV (77.1%), and AUC (0.70). Similarly, PSI class V showed the highest Youden index (0.35), specificity (68.3%), PPV (51.1%), NPV (80.5%), and AUC (0.69) for IRVS. CONCLUSIONS: The PSI has superior discriminatory power in predicting all three clinical outcomes (30-day mortality, severe pneumonia, and IVRS) compared with the NHAP model score, CURB-65 and SOAR.

Usability of ringed polytetrafluoroethylene grafts for middle hepatic vein reconstruction during living donor liver transplantation.

Large vein allografts are suitable for middle hepatic vein (MHV) reconstruction, but their supply is often limited. Although polytetrafluoroethylene (PTFE) grafts are unlimitedly available, their long-term patency is relatively poor. We intended to enhance the clinical usability of PTFE grafts for MHV reconstruction during living donor liver transplantation (LDLT). Two sequential studies were performed. First, PTFE grafts were implanted as inferior vena cava replacements into dogs. Second, in a 1-year prospective clinical trial of 262 adults undergoing LDLT with a modified right lobe, MHV reconstruction with PTFE grafts was compared with other types of reconstruction, and the outcomes were evaluated. In the animal study, PTFE grafts induced strong inflammatory reactions and luminal thrombus formation, but the endothelial lining was well developed. In the clinical study, the reconstruction techniques were revised to make a composite PTFE graft with an artery patch on the basis of the results of the animal study. MHVs were reconstructed with cryopreserved iliac veins (n = 122), iliac arteries (n = 43), aortas (n = 13), and PTFE (n = 84), and these reconstructions yielded 6-month patency rates of 75.3%, 35.2%, 92.3%, and 76.6%, respectively. The overall 6-month patency rates for the iliac vein and PTFE grafts were similar (P = 0.92), but the 6-month patency rates with vein segment 5 were 51.0% and 34.7%, respectively (P = 0.001). The overall graft and patient survival rates did not differ among these 4 groups. In conclusion, ringed PTFE grafts combined with small vessel patches showed high patency rates comparable to those of iliac vein grafts; thus, they can be used for MHV reconstruction when other sizable vessel allografts are not available.

Hemodynamics-compliant reconstruction of the right hepatic vein for adult living donor liver transplantation with a right liver graft.

Secure reconstruction of the right hepatic vein (RHV) is essential for the successful implantation of a right liver graft during living donor liver transplantation (LDLT). To develop reliable surgical techniques for RHV reconstruction, we performed 3 concurrent studies: a simulation study using a fluid dynamics experimental model and a computational simulation model; an observational study analyzing the hemodynamic changes during radiological interventions for RHV stenosis; and a prospective clinical study establishing hemodynamics-compliant surgical techniques. The simplified fluid dynamics experimental model revealed that actually measured outflow volumes were very similar to theoretical values derived from a fluid dynamics formula. The computational simulation model showed that outflow decreases were nearly linearly correlated with the degree of stenosis when it exceeded 50%. The clinical observational study revealed that mild (≤50%), moderate (50%-75%), and severe RHV stenoses (≥75%) had mean pressure gradients of 2.5 ± 1.0, 6.6 ± 2.3, and 9.6 ± 2.8 mm Hg, respectively. The prospective clinical study was performed for patients who underwent RHV reconstruction with RHV angle blunting and inferior vena cava enlargement (n = 274); a historical control group of patients who underwent reconstruction by other methods (n = 225) was also used. RHV stenting within 2 weeks and 1 year was necessary for 1 patient (0.4%) and 5 patients (1.8%) in the study group, respectively, and for 9 patients (4.0%) and 21 patients (9.1%) in the control group, respectively (P < 0.01). The mean cephalocaudal length of patulous RHV anastomoses was greater in the study group versus the control group (P < 0.001). In conclusion, our modified RHV reconstruction technique significantly reduces the risk of RHV stenosis. We thus suggest the routine or selective use of this technique as a part of graft standardization for LDLT using a right liver graft.

Experience and analysis of Delphian lymph node metastasis in patients with papillary thyroid carcinoma.

BACKGROUND: Recently, lymph node metastasis (LNM) has been regarded as an important factor influencing loco-regional recurrence and survival rate in papillary thyroid cancer (PTC) patients. The aims of this study were to investigate the detection rate and metastasis rate of the Delphian lymph node (DLN) and clinical patterns related to regional LNM, and to examine how DLN metastasis affects PTC treatment. METHODS: We reviewed the medical records of 413 patients with pathologically confirmed PTC from among 452 patients who underwent thyroid surgery between January 2010 and October 2010 in the Department of Endocrine Surgery at Kosin University Gospel Hospital in Busan, South Korea. RESULTS: Multivariate analyses revealed a significantly higher proportion of cases with lymphovascular invasion (56.6% vs. 12.5%, P <0.001), central neck node metastasis (88.6% vs. 34.5%, P <0.001) and lateral neck node metastasis (47.2% vs. 10.2%, P <0.005) among cases with DLN metastasis compared to those without. The negative predictive value (NPV) of DLN metastasis with regard to the presence of contralateral central LNM for cases with a tumor size 1 cm or smaller than 1 cm was found to be 93.3% (127/136). CONCLUSION: When DLN metastasis is not detected in papillary thyroid microcarcinomas (PTMC), thyroid lobectomy on the affected side and ipsilateral central neck lymph node dissection should be sufficient. In addition, even in cases where lateral neck LNM is not detected on preoperative examination, if DLN metastasis is detected postoperatively, more careful attention should be paid to the lateral neck nodes during follow-up.

Technique of antegrade intraoperative cholangiography not requiring hepatic hilar dissection during repeated hepatectomy for hepatocellular carcinoma.

It is important to perform intraoperative cholangiography (IOC) during liver resection in order to detect bile leaks, but its performance is not so simple during repeat hepatectomy. We describe the technique of antegrade intraoperative cholangiography not requiring hepatic hilar dissection during repeated hepatectomy. The patient was a 35-year-old female who had undergone 4 previous operations for hepatocellular carcinoma. During the fifth operation, it was not possible to dissect the hepatic hilum only for taking IOC because of heavy adhesion. A small-sized intrahepatic glissonian branch was isolated during parenchymal transection, which was later used for an infusion route of IOC. A 24-gauge angiocatheter was inserted into the intrahepatic bile duct stump and tied over the whole glissonian pedicle stump. An IOC was successfully taken through this catheter and the glissonian pedicle stump was ligated after a leak test using methylene blue solution. At 32 months after this hepatectomy, she underwent deceased- donor liver transplantation due to hepatic failure from bile duct invasion by recurrent tumor. During recipient hepatectomy, previous minimal hilar dissection appeared very beneficial because some of the hilar structures remained undissected. This technique of antegrade IOC through the intrahepatic bile duct within the glissonian pedicle allows for an IOC without additional manipulation of the hepatoduodenal ligament when the cystic duct stump is not available.

The effects of smoking on the relationship between metabolic syndrome and arterial stiffness.

It has been reported that arterial stiffness assessed by pulse wave velocity (PWV) can predict cardiovascular morbidity and mortality. Metabolic syndrome and smoking are independently associated with increased risk of cardiovascular disease. The purpose of this study was to evaluate the effect of smoking on the relationship between metabolic syndrome and arterial stiffness. We retrospectively enrolled 1,530 men on whom brachial-ankle pulse wave velocity (baPWV) measurement had previously been performed as part of health screening at Kosin University Hospital. We found that PWV was positively correlated with the following variables: age (r = 0.391, P < 0.0001), systolic blood pressure (r = 0.438, P < 0.0001), diastolic blood pressure (r = 0.377, P < 0.0001), low-density lipoprotein (LDL) (r = 0.068, P = 0.008) and high-density lipoprotein (HDL) (r = 0.027, P = 0.287), whereas BMI was negatively correlated, although without statistical significance (r = -0.026, P = 0.309). Among current smokers, PWV decreased with increasing BMI (from 1,387.9 to 1,311.6), and increased with increasing HDL (from 1,342.7 to 1,385.4). On the other hand, among never smokers, PWV increased with increasing BMI (from 1,382.3 to 1,458.8), and decreased with increasing HDL (from 1,391.2 to 1,369.7). PWV was inversely associated with BMI and HDL, and these differences are likely due to smoking.

Building a Korean morphological analyzer using two Korean BERT models.

A morphological analyzer plays an essential role in identifying functional suffixes of Korean words. The analyzer input and output differ from each other in their length and strings, which can be dealt with by an encoder-decoder architecture. We adopt a Transformer architecture, which is an encoder-decoder architecture with self-attention rather than a recurrent connection, to implement a Korean morphological analyzer. Bidirectional Encoder Representations from Transformers (BERT) is one of the most popular pretrained representation models; it can present an encoded sequence of input words, considering contextual information. We initialize both the Transformer encoder and decoder with two types of Korean BERT, one of which is pretrained with a raw corpus, and the other is pretrained with a morphologically analyzed dataset. Therefore, implementing a Korean morphological analyzer based on Transformer is a fine-tuning process with a relatively small corpus. A series of experiments proved that parameter initialization using pretrained models can alleviate the chronic problem of a lack of training data and reduce the time required for training. In addition, we can determine the number of layers required for the encoder and decoder to optimize the performance of a Korean morphological analyzer.

Neuroendocrine Tumor with Metachronous Gastrointestinal Stromal Tumor in a Patient: A Case Report.

Neuroendocrine tumors (NETs) that arise from neuroendocrine cells can develop in most organs; however, it is rarely found in the duodenal papilla. Conversely, gastrointestinal stromal tumors (GISTs), which are mostly asymptomatic and detected incidentally, are usually found in the stomach and very rarely occur metachronously with NETs. A 42-year-old female with no specific underlying disease underwent gastroscopy due to epigastric pain. Biopsy of enlarged major and minor duodenal papilla confirmed the diagnosis of a NET. Endoscopic papillectomy of the major and minor papillae was performed. Multiple duodenal and jejunal submucosal nodules were seen on biliary CT performed at the 30 months follow-up. Pylorus-preserving pancreaticoduodenectomy was performed due to the suspicion of multiple recurrent NETs and muscularis propria involvement on endoscopic ultrasound. Surgical specimen biopsy confirmed the diagnosis of multiple duodenal and jejunal GIST lesions and a metastatic NET in the duodenal lymph node. We report a rare case of a GIST detected in the duodenum during follow-up after the diagnosis and papillectomy of duodenal papilla NET.