Jong Eun Yeon

Korea University, Sŏul, Seoul, South Korea

Are you Jong Eun Yeon?

Claim your profile

Publications (174)848.23 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Aims: Pancreatic cystic neoplasms (PCN) with malignant potential are thought to be less aggressive than ordinary ductal adenocarcinoma, even in the setting of malignant transformation. Therefore, deciding whether or not to carry out surgery is very difficult, especially in elderly and asymptomatic patients, because of the high risk of perioperative morbidities. The aim of the present study was to examine clinical outcomes of PCN patients aged 65 years or older. Methods: This retrospective analysis included patients with incidentally detected PCN with follow-up durations >1 year. Patients diagnosed with obvious simple cysts, pseudocysts or pancreatic cancer and patients with a history of pancreatic disease were excluded from the study. Results: The present study included 201 patients (older group 104 patients ≥65 years; younger group 97 patients <65 years). Surgical resections were carried out for 27 patients in the older group and 41 patients in the younger group. There were 133 patients who were followed up without surgery (mean follow-up duration 41 months). Postoperative morbidity occurred in 22.2% of the patients in the older group and 21.9% of the patients in the younger group. Malignancy occurred in one patient in the older group and in two patients in the younger group. The PCN diameter increased in 20 patients during follow up: 16.9% of the older group and 12.5% of the younger group. Conclusions: The malignancy rate was very low in incidental PCN patients irrespective of age. Follow-up observation without surgery appears to be a safe option in older patients with morbidity. Geriatr Gerontol Int 2016; ●●: ●●-●●.
    No preview · Article · Feb 2016 · Geriatrics & Gerontology International
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Purpose: Hepatocellular carcinomas are one of the most common malignancies in the world. However, no effective therapeutic modality has been proven to prolong the survival of patients in an inoperable stage. The purpose of this study was to determine the response rate and the toxicities of a combination of pirarubicin, UFT and leucovorin in patients with non-embolizable hepatocellular carcinomas, or who had progressed during their transcatheter arterial chemoembolization treatment. Materials and methods: Of 23 patients with a hepatocellular carcinoma, 11 had progressed during a transcatheter arterial chemoembolization, with the other 12 being transcatheter arterial chemoembolization-naive. All the patients were treated with pirarubicin (70 mg/m2 i.v., day 1), UFT (350 mg/m2 P.O., day 1~21), and leucovorin (25 mg/m2 P.O., day 1~21). Results: Twenty patients were able to be evaluated, with a partial response being achieved in four, giving an overall response rate of 20% (95% confidence interval, 7~44%). The median overall survival time was 6 months, and the median survival time of the transcatheter arterial chemoembolization-naive patients was significantly longer than that of those treated by transcatheter arterial chemoembolization (p=0.012). The most significant dose-limiting toxicity was leucopenia and thrombocytopenia. Conclusion: The combination of pirarubicin, UFT and leucovorin therapies showed marginal antitumor activity and significant toxicity in patients with non-embolizable or failed transcatheter arterial chemoembolization hepatocellular carcinomas.
    Preview · Article · Dec 2015 · Cancer Research and Treatment
  • [Show abstract] [Hide abstract]
    ABSTRACT: Objectives: We evaluated the value of carbohydrate antigen 19-9 (CA 19-9) as a pancreatic cancer (PC) screening tool in an asymptomatic new-onset diabetic patients. Methods: Medical records of asymptomatic patients newly diagnosed with diabetes mellitus (DM) were reviewed retrospectively at our hospital from January 2004 to January 2013. Results: In total, 2363 asymptomatic diabetic patients with CA 19-9 measurements were enrolled. Of them, 68 (2.9%) were diagnosed with PC. In the 1719 patients who had CA 19-9 measured within 1 year after the DM diagnosis, a total of 51 (3.0 %) patients developed PC and the odds ratio (OR) of PC according to higher CA 19-9 than normal upper limit, 37 IU/mL was 5.57 (P < 0.001). In 248 patients checked CA 19-9 between 1 and 2 years after DM diagnosis, PC was detected in 9 (3.6%) cases and OR of high CA 19-9 was 4.51 (P = 0.019). However, beyond 2 years, the OR for PC showed no statistical significance. The patients with high CA 19-9 levels tended to have more advanced-stage disease. Conclusions: Early check-up of CA 19-9 could be a useful marker for screening for PC in asymptomatic patients with new-onset DM in the first 2 years.
    No preview · Article · Dec 2015 · Pancreas
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background and aims: There has been remarkable progress in the management of hepatocellular carcinoma (HCC) during the last several decades but its effect on the prognosis of HCC patient needs clarification. We analyzed the changes that affected prognosis of HCC patients diagnosed over two different eras. Methods: A retrospective study of 1318 patients diagnosed with HCC from 1986 to 2012 was conducted. Analysis was done according to two cohorts, cohort 1 (patients diagnosed with HCC from 1986 to 1992) and cohort 2 (patients diagnosed from 2006 to 2012). Results: Hepatitis B virus was the most common cause of liver disease for both cohorts (66.2% and 66.0%). The proportion of patients with Barcelona Clinic Liver Cancer stage 0/A was significantly lower in cohort 1 than in cohort 2 (14.4% vs. 39.5%, P<0.001). The proportions of patients diagnosed during surveillance and general health-check were significantly higher in cohort 2 than in cohort 1 (28.6% vs. 10.6% and 26.3% vs. 7.9%, respectively) while those diagnosed during symptomatic evaluation was significantly higher in cohort 1 than in cohort 2 (45.1 vs. 81.4%, P<0.001). Surgical resection rate was similar between the two cohorts (26.1% vs 26%) while the transcatheter arterial chemoembolization rate which was highest in cohort 1 (40.6%) was overtaken by radiofrequency ablation in cohort 2 (55%) at BCLC stage 0/A. Median survival duration in cohort 2 was significantly longer than cohort 1 (65.0 vs. 7.9 months, P<0.001). Conclusions: Implementation of national cancer surveillance and the advancement of treatment modalities have likely led to the early detection of HCC and improvements in prognosis over the last 20 years. This article is protected by copyright. All rights reserved.
    No preview · Article · Sep 2015 · Liver international: official journal of the International Association for the Study of the Liver
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background and AimAlthough the Barcelona Clinic Liver Cancer (BCLC) staging system is widely used for hepatocellular carcinoma (HCC) staging, the most appropriate BCLC stage designation for single large HCC (SLHCC, single nodule >5 cm) remains controversial. This study investigated the prognosis of patients with SLHCC.Methods Patients with newly diagnosed HCCs (BCLC stages A or B) were classified according to tumor burden: group 1, a single nodule >2 cm and ≤5 cm or 2 ~ 3 nodules ≤3 cm; group 2, a single nodule >5 cm; and group 3, 2 or 3 nodules >3 cm or >3 nodules. Survival analysis was performed according to tumor stage, treatment type, and Child-Pugh grade.ResultsA total of 1005 patients were enrolled. Age was 59.3 ± 10.6 years and 788 patients (78.4%) were men. Groups 1, 2, and 3 consisted of 613 (61.0%), 124 (12.3%), and 268 (26.7%) patients, respectively. HCC treatment included resection in 202 patients (20.1%), radiofrequency ablation ± transarterial chemoembolization (TACE) in 311 patients (30.9%), and TACE in 492 patients (49.0%). The median survival time differed significantly according to tumor stage (75.2, 44.9, and 30.3 months in groups 1, 2, and 3, respectively; P < 0.001). Multivariate analysis showed that group 2 had significantly worse survival compared to group 1 and similar survival to group 3.Conclusions Patients in group 2 had a worse prognosis than those in group 1 and a similar prognosis to those in group 3. Our results suggest that BCLC stage B is the best stage designation for SLHCC. This article is protected by copyright. All rights reserved.
    No preview · Article · Sep 2015 · Journal of Gastroenterology and Hepatology
  • [Show abstract] [Hide abstract]
    ABSTRACT: Entecavir (ETV) induces biochemical and histologic improvement of the liver in patients with chronic hepatitis B. This study aimed to confirm that 2 years of ETV treatment improves liver function and non-invasive fibrosis markers in patients with hepatitis B virus (HBV)-associated cirrhosis. A total 472 naïve patients with HBV-associated cirrhosis was treated with ETV for at least 2 years, between March 2007 and December 2012. Model for end-stage liver disease (MELD) and Child-Pugh (CP) score were used to evaluate the improvement of liver function. Aspartate transaminase to platelet ratio index (APRI), FIB-4 index, and fibrosis index (FI) were used to evaluate the improvement of fibrosis. The final 370 of 472 patients with HBV-associated cirrhosis were enrolled. Mean age was 51 ± 10 years and 240 patients (64.9%) were men. The distribution of CP class was 71.1% in A, 24.6% in B, and 4.3% in C. Mean MELD and CP score changed over the study period from 8.5 ± 4.6 to 6.2 ± 4.2 (P < 0.001) and from 6.2 ± 1.6 to 5.6 ± 0.9 (P < 0.001), respectively. APRI, FIB-4 index, and FI changed from 3.6 ± 4.5 to 1.5 ± 1.5 (P < 0.001), from 7.0 ± 6.2 to 3.9 ± 2.8 (P < 0.001), and from 3.3 ± 0.9 to 2.5 ± 1.1 (P < 0.001), respectively. After 2 years of treatment, entecavir improves liver function and non-invasive fibrosis markers in patients with HBV- associated cirrhosis. This article is protected by copyright. All rights reserved.
    No preview · Article · Jun 2015 · Journal of Gastroenterology and Hepatology
  • [Show abstract] [Hide abstract]
    ABSTRACT: The guideline for the management of hepatocellular carcinoma (HCC) was first developed in 2003 and revised in 2009 by the Korean Liver Cancer Study Group and the National Cancer Center, Korea. Since then, many studies on HCC have been carried out in Korea and other countries. In particular, a substantial body of knowledge has been accumulated on diagnosis, staging, and treatment specific to Asian characteristics, especially Koreans, prompting the proposal of new strategies. Accordingly, the new guideline presented herein was developed on the basis of recent evidence and expert opinions. The primary targets of this guideline are patients with suspicious or newly diagnosed HCC. This guideline provides recommendations for the initial treatment of patients with newly diagnosed HCC.
    No preview · Article · May 2015
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The guideline for the management of hepatocellular carcinoma (HCC) was first developed in 2003 and revised in 2009 by the Korean Liver Cancer Study Group and the National Cancer Center, Korea. Since then, many studies on HCC have been carried out in Korea and other countries. In particular, a substantial body of knowledge has been accumulated on diagnosis, staging, and treatment specific to Asian characteristics, especially Koreans, prompting the proposal of new strategies. Accordingly, the new guideline presented herein was developed on the basis of recent evidence and expert opinions. The primary targets of this guideline are patients with suspicious or newly diagnosed HCC. This guideline provides recommendations for the initial treatment of patients with newly diagnosed HCC.
    Full-text · Article · May 2015 · Korean Journal of Radiology
  • Source

    Preview · Article · May 2015 · The Korean Journal of Internal Medicine

  • No preview · Article · Apr 2015

  • No preview · Article · Apr 2015 · Journal of Hepatology
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: No adjuvant therapy has been shown to extend survival of patients with hepatocellular carcinoma (HCC) receiving curative treatment. We investigated whether injections of activated cytokine-induced killer (CIK) cells (CD3+/CD56+ and CD3+/CD56- T cells and CD3-/CD56+ natural killer cells) prolongs recurrence-free survival of patients following curative therapy for HCC. We performed a multi-center, randomized, open-label, phase 3 trial of the efficacy and safety of adjuvant immunotherapy with activated CIK cells (created by incubation of patients' peripheral blood mononuclear cells with interleukin-2 and an antibody against CD3). The study included 230 patients with HCC treated by surgical resection, radiofrequency ablation, or percutaneous ethanol injection at university-affiliated hospitals in Korea. Patients were randomly assigned to receive immunotherapy (injection of 6.4 ×10⁹ autologous CIK cells, 16 times during 60 weeks) or no adjuvant therapy (controls). The primary endpoint was recurrence-free survival; secondary endpoints included overall survival, cancer-specific survival, and safety. The median time of recurrence-free survival was 44.0 months in the immunotherapy group and 30.0 months in the control group (hazard ratio [HR] with immunotherapy, 0.63; 95% confidence interval [CI], 0.43-0.94; P=.010 by one-sided log-rank test). HRs were also lower in the immunotherapy than control group for all-cause death (0.21; 95% CI, 0.06-0.75; P=.008) and cancer-related death (0.19; 95% CI, 0.04-0.87; P=.02). A significantly higher proportion of patients in the immunotherapy group than the control group had an adverse event (62% vs 41%, P=.002), but the proportion of patients with serious adverse events did not differ significantly between groups (7.8% vs 3.5%, P=.15). In patients who underwent curative treatment for HCC, adjuvant immunotherapy with activated CIK cells increased recurrence-free and overall survival. ClinicalTrials.gov number: NCT00699816. Copyright © 2015 AGA Institute. Published by Elsevier Inc. All rights reserved.
    Full-text · Article · Mar 2015 · Gastroenterology
  • [Show abstract] [Hide abstract]
    ABSTRACT: To evaluate the effects of butein on inflammatory cytokines, matrix metalloproteinase-9 (MMP-9), and colitis in interleukin (IL)-10(-/-) mice. To synchronize colitis, 8- to 10-wk-old IL-10(-/-) mice were fed pellet-chow containing piroxicam for 2 wk. Subsequently, phosphate-buffered saline or butein (1 mg/kg per day, ip) was injected for 4 wk. Histologic scores, inflammatory cytokines, MMP-9 and phosphorylated signal transducer and activator of transcription 3 (pSTAT3) expressions were analyzed in IL-10(-/-) mice and in Colo 205 cells. Butein reduced the colonic inflammatory score by > 50%. Expression levels of IL-6, IL-1β, interferon (IFN)-γ and MMP-9 were decreased in the colons of mice exposed to butein, whereas other inflammatory cytokines (IL-17A, IL-21 and IL-22) were unchanged. Immunohistochemical staining for pSTAT3 and MMP-9 was significantly decreased in the butein-treated groups compared with the controls. Butein inhibited IL-6-induced activation of STAT3 in Colo 205 cells. Butein ameliorated colitis in IL-10(-/-) mice by regulating IL-6/STAT3 and MMP-9 activation.
    No preview · Article · Jan 2015
  • [Show abstract] [Hide abstract]
    ABSTRACT: Objectives: Interferon (IFN)-based therapy for chronic hepatitis C (CHC) is cost-effective and is associated with reduced risk of disease progression. We aimed to assess the incidence of cirrhosis and hepatocellular carcinoma (HCC) and to identify risk factors associated with disease progression. Methods: We retrospectively reviewed 280 CHC patients who were registered at our hospital between 2001 and 2010. Results: About 80% of patients received antiviral treatment. The 10-year cumulative incidence of cirrhosis was significantly lower among patients who received antiviral therapy than among those who did not (8.3 vs. 44.0%; p = 0.001). Among them, patients with sustained virological response (SVR) had a significantly lower incidence of cirrhosis than those without SVR (0.6 vs. 33.9%; p < 0.001). Cox proportional hazards regression showed that SVR was the significant independent factor for reducing the risk of cirrhosis (hazard ratio, HR = 0.03; p = 0.034). The 10-year cumulative incidence of HCC was higher among patients who did not receive antiviral therapy than among those who did (43.9 vs. 6.1%; p < 0.001). Multivariate analysis showed that underlying cirrhosis was the only independent risk factor associated with HCC development (HR = 7.70; p = 0.010). Conclusions: SVR secondary to IFN-based therapy could reduce cirrhosis development in CHC patients. Underlying cirrhosis was the strongest predictor of HCC development.
    No preview · Article · Jan 2015 · Intervirology
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Prothrombin induced by vitamin K deficiency or antagonist II (PIVKA-II) is a widely used diagnostic marker for hepatocellular carcinoma (HCC). We evaluated the correlation between alcoholic liver disease (ALD) and serum PIVKA-II levels in chronic liver disease (CLD) patients. We retrospectively reviewed the medical records of 2,528 CLD patients without HCC. Among these patients, 76 exhibited serum high PIVKA-II levels of >125 mAU/mL (group 1). We categorized 76 control patients matched by age, sex, and the presence of liver cirrhosis from the remaining patients who were negative for serum PIVKA-II (group 2). Group 1 revealed increased antibiotic usage (23.7% vs 2.6%, p<0.001) and incidence of ALD (60.5% vs 14.5%, p<0.001) as well as elevated aspartate aminotransferase (52.5 IU/L vs 30.5 IU/L, p=0.025) and γ glutamyl transpeptidase (67.5 IU/L vs 36.5 IU/L, p=0.005) levels compared with group 2. Further, group 1 was significantly associated with a worse Child-Pugh class than group 2. In the multivariate analysis, ALD (odds ratio [OR], 7.151; p<0.001) and antibiotic usage (OR, 5.846; p<0.001) were significantly associated with positive PIVKA-II levels. Our study suggests that ALD and antibiotics usage may be confounding factors when interpreting high serum PIVKA-II levels in patients without HCC. Therefore, serum PIVKA-II levels in patients with ALD or in patients administered antibiotics should be interpreted with caution. (Gut Liver, Published online December 5, 2014).
    Preview · Article · Dec 2014 · Gut and liver
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Systematic analysis of gene expression data from human liver undergoing hepatic injury and regeneration revealed a 233-gene signature that was significantly associated with late recurrence of HCC. Using this signature, we developed a prognostic predictor that can identify patients at high risk of late recurrence, and tested and validated the robustness of the predictor in patients (n = 396) who underwent surgery between 1990 and 2011 at four centers (210 recurrences during a median of 3.7 y of follow-up). In multivariate analysis, this signature was the strongest risk factor for late recurrence (hazard ratio, 2.2; 95% confidence interval, 1.3–3.7; p = 0.002). In contrast, our previously developed tumor-derived 65-gene risk score was significantly associated with early recurrence (p = 0.005) but not with late recurrence (p = 0.7). In multivariate analysis, the 65-gene risk score was the strongest risk factor for very early recurrence (<1 y after surgical resection) (hazard ratio, 1.7; 95% confidence interval, 1.1–2.6; p = 0.01). The potential significance of STAT3 activation in late recurrence was predicted by gene network analysis and validated later. We also developed and validated 4- and 20-gene predictors from the full 233-gene predictor. The main limitation of the study is that most of the patients in our study were hepatitis B virus–positive. Further investigations are needed to test our prediction models in patients with different etiologies of HCC, such as hepatitis C virus.
    Full-text · Article · Dec 2014 · PLoS Medicine
  • [Show abstract] [Hide abstract]
    ABSTRACT: Goals: The aim of this study was to evaluate the risk factors and clinical significance of terlipressin-induced hyponatremia. Background: Patients receiving terlipressin treatment frequently develop hyponatremia. However, its clinical significance and risk factors are not fully elucidated. Study: Records of patients treated with terlipressin for variceal bleeding were analyzed. Hyponatremia was defined as a decrease in serum sodium (Na) level of >5 mEq/L from the baseline level; severe hyponatremia as a decrease in serum Na level of >10 mEq/L from the baseline level; and rapid severe hyponatremia as a decrease in serum Na level of >10 mEq/L within 3 days of treatment. Results: The study involved 151 patients (mean age, 55.1+/-11.8 y) with male predominance (80.8%). Baseline serum Na and creatinine levels were 137.2+/-6.1 mEq/L and 0.9+/-0.4 mg/dL, respectively. Patients were treated with terlipressin for 4.5+/-1.9 days. Changes in serum Na levels from baseline were 0.4+/-4.1, -1.1+/-4.8, -4.0+/-7.0, -6.5+/-9.1, and -6.1+/-11.2 mEq/L, whereas the frequencies of hyponatremia and severe hyponatremia were 13.6%, 30.4%, 50.8%, 63.5%, and 66.9% and 0%, 8.8%, 23.3%, 33.0%, and 38.8% on days 1, 2, 3, 4, and 5 of treatment, respectively. Younger age, lower Child-Pugh score, higher serum Na level, and longer duration of terlipressin treatment were independent risk factors. Rapid severe hyponatremia developed in 29 patients (19.2%); lower body mass index was an additional risk factor in this group. Mortality was not associated with hyponatremia. Conclusions: Terlipressin-induced hyponatremia occurred frequently, especially in young patients with good liver function and higher Na level. Caution is required when administering terlipressin to patients with low body mass index. Copyright
    No preview · Article · Sep 2014 · Journal of Clinical Gastroenterology
  • Source
    Jong Eun Yeon
    [Show abstract] [Hide abstract]
    ABSTRACT: Since the discovery of HBsAg in the early 1960s, presence of HBsAg in serum has only served to diagnose hepatitis B. Recent development in the quantitative measurement of serum HBsAg has enabled us to improve our understanding on the management of chronic hepatitis B. The surface antigen (sAg) level is at its highest in immune tolerance phase and decreases to the lowest level in immune control/inactive phase when HBeAg is cleared from the serum. Combination of serum sAg titer less than 1,000 IU/mL and serum HBV DNA less than 2,000 IU/mL can identify true inactive carrier from e antigen (eAg) negative hepatitis with diagnostic accuracy of 95%. During the natural course of chronic hepatitis B, changes or absolute level of sAg less than certain level can predict spontaneous sero-clearance of HBsAg. Although the decline of sAg is very slow in interferon (IFN)/pegylated interferon (PEG-IFN) or oral nucleos(-t)ide treated patients, interferon based therapy results in a greater decrease of sAg level and sAg loss. Lack of any decline in sAg titer during PEG-IFN therapy could identify the group of patients who do not response to IFN/PEG-IFN therapy. With the aid of serum HBV DNA, quantitative measurement of serum HBsAg level can be used to optimize the management of chronic hepatitis B in our daily practice. (Korean J Gastroenterol 2014;63:335-340).
    Preview · Article · Jun 2014 · The Korean journal of gastroenterology = Taehan Sohwagi Hakhoe chi
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background & AimsEntecavir (ETV) is effective in the treatment of chronic hepatitis B virus (HBV) infections, even in patients with underlying cirrhosis. However, there is little information on the effect of telbivudine (TBV) in chronic hepatitis B patients with cirrhosis.This study compared the antiviral efficacy of TBV and ETV in HBV-related cirrhosis.Methods We consecutively enrolled 151 treatment-naïve patients with HBV-related cirrhosis who started antiviral therapy with TBV (n = 61) or ETV (n = 90).ResultsAfter 24 months of treatment, per-protocol analysis showed similar virological response rates (HBV DNA <20 IU/ml) in the TBV group (80.6%, 25/31) and in the ETV group (90.2%, 74/82) (P = 0.167). However, intention-to-treat analysis showed lower virological response rates in the TBV group (41.7%, 25/60) than in the ETV group (83.1%, 74/89) (P = 0.001). Mean reduction in HBV DNA levels was greater in the ETV group (−3.72 ± 1.94 vs. −4.87 ± 1.57 respectively, P = 0.001). Serologic and biochemical response rates at month 24 did not differ significantly between the groups. Child-Turcotte-Pugh score was significantly improved after 24 months compared to the pretreatment state without difference between the groups. During 24 months of therapy, 15 patients (27.3%) showed antiviral resistance to TBV while no resistance (0%) was reported in the ETV group (P = 0.001).Conclusions Compared to ETV, TBV therapy shows lower efficacy in viral suppression and higher risk of antiviral resistance despite comparable effect on improvement of hepatic function for the treatment of HBV-related cirrhosis.
    No preview · Article · Jun 2014 · Liver international: official journal of the International Association for the Study of the Liver

  • No preview · Article · Apr 2014 · Journal of Hepatology

Publication Stats

1k Citations
848.23 Total Impact Points

Institutions

  • 1998-2015
    • Korea University
      • • Department of Internal Medicine
      • • Department of Gastroenterology
      Sŏul, Seoul, South Korea
  • 2012
    • Kyungpook National University
      • Department of Internal Medicine
      Daikyū, Daegu, South Korea
    • Sun Yat-Sen University
      • Department of Infectious Diseases
      Shengcheng, Guangdong, China
  • 2011
    • Seoul Medical Center
      Sŏul, Seoul, South Korea
    • University of Ioannina
      • School of Medicine
      Yannina, Epirus, Greece
  • 2010
    • Inje University
      Kŭmhae, South Gyeongsang, South Korea
  • 2006-2010
    • Konkuk University Medical Center
      • Department of Laboratory Medicine
      Changnyeong, South Gyeongsang, South Korea
    • Yonsei University
      Sŏul, Seoul, South Korea
  • 2007
    • Yonsei University Hospital
      • Department of Internal Medicine
      Sŏul, Seoul, South Korea
    • Inje University Paik Hospital
      • Department of Internal Medicine
      Goyang, Gyeonggi, South Korea
  • 2006-2007
    • Konkuk University
      • Department of Internal medicine
      Sŏul, Seoul, South Korea
  • 2004-2006
    • Hallym University Medical Center
      • Department of Internal Medicine
      Seoul, Seoul, South Korea
  • 2005
    • Kangwon National University Hospital
      Shunsen, Gangwon, South Korea
  • 2003
    • Rhode Island Hospital
      Providence, Rhode Island, United States
  • 2002
    • Korea University Medical Center
      Sŏul, Seoul, South Korea