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Hyuk Lee

Publications and source records attributed to Hyuk Lee.

12 recordsLinked to original sources
PubMed2026

C-Reactive Protein-Based Composite Indices for Predicting Tumor Overgrowth Restenosis After Partially Covered Duodenal Stenting in Gastric Cancer: A Cohort Study.

BACKGROUND/OBJECTIVES: Partially covered duodenal stents rapidly relieve malignant gastric outlet obstruction, but tumor overgrowth restenosis limits durability. We compared six preprocedural inflammatory, nutritional, and immune indices for predicting this outcome in patients with gastric cancer. METHODS: We retrospectively analyzed 68 consecutive patients from a prospectively maintained cohort. The primary endpoint was endoscopically or radiologically confirmed tumor overgrowth restenosis. Discrimination was assessed using receiver operating characteristic curves (pairwise DeLong tests with Bonferroni correction) and time-dependent areas under the curve (AUCs) accounting for death as a competing risk. Multivariable cause-specific Cox models were restricted to preprocedural covariates; post-stenting chemotherapy or radiotherapy was examined in time-dependent sensitivity analyses. RESULTS: Technical and clinical success rates were 100% and 94.1%. Seventeen patients (25.0%) developed restenosis at a median of 66 days. The C-reactive protein-albumin-lymphocyte (CALLY) index showed the highest AUC (0.859), followed by the C-reactive protein-to-albumin ratio (CAR; 0.822) and neutrophil-to-lymphocyte ratio (0.774); these three indices did not differ significantly. At an exploratory, internally derived cutoff of ≤0.110, CALLY had 76.5% sensitivity and 84.3% specificity and remained associated with restenosis after adjustment for stenosis site and stent length (adjusted hazard ratio, 12.30; 95% confidence interval, 3.89-38.83; C-index, 0.836), with consistent results in continuous, time-dependent, and tumor-covariate-adjusted analyses. The 180-day cumulative incidence was 52.4% with low CALLY versus 4.3% with high CALLY. CONCLUSIONS: C-reactive protein-based indices showed the highest numerical discrimination, although pairwise differences among CALLY, CAR, and NLR were not statistically significant. CALLY is a promising exploratory biomarker for restenosis risk stratification, but its cutoff should not guide clinical decisions until externally validated.

C-reactive protein↗
PubMed2024

Stool Protein Mass Spectrometry Identifies Biomarkers for Early Detection of Diffuse-type Gastric Cancer.

There is a high unmet need for early detection approaches for diffuse gastric cancer (DGC). We examined whether the stool proteome of mouse models of gastric cancer (GC) and individuals with hereditary diffuse gastric cancer (HDGC) have utility as biomarkers for early detection. Proteomic mass spectrometry of the stool of a genetically engineered mouse model driven by oncogenic KrasG12D and loss of p53 and Cdh1 in gastric parietal cells [known as Triple Conditional (TCON) mice] identified differentially abundant proteins compared with littermate controls. Immunoblot assays validated a panel of proteins, including actinin alpha 4 (ACTN4), N-acylsphingosine amidohydrolase 2 (ASAH2), dipeptidyl peptidase 4 (DPP4), and valosin-containing protein (VCP), as enriched in TCON stool compared with littermate control stool. Immunofluorescence analysis of these proteins in TCON stomach sections revealed increased protein expression compared with littermate controls. Proteomic mass spectrometry of stool obtained from patients with HDGC with CDH1 mutations identified increased expression of ASAH2, DPP4, VCP, lactotransferrin (LTF), and tropomyosin-2 relative to stool from healthy sex- and age-matched donors. Chemical inhibition of ASAH2 using C6 urea ceramide was toxic to GC cell lines and GC patient-derived organoids. This toxicity was reversed by adding downstream products of the S1P synthesis pathway, which suggested a dependency on ASAH2 activity in GC. An exploratory analysis of the HDGC stool microbiome identified features that correlated with patient tumors. Herein, we provide evidence supporting the potential of analyzing stool biomarkers for the early detection of DGC. Prevention Relevance: This study highlights a novel panel of stool protein biomarkers that correlate with the presence of DGC and has potential use as early detection to improve clinical outcomes.

Feces↗
PubMed2006

Clinical features and prognosis of hepatocellular carcinoma in young patients from a hepatitis B-endemic area.

BACKGROUND AND AIM: Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. However, the clinical features of young HCC patients have not been fully studied. In the present study, we investigated the prevalence, clinical characteristics and prognosis of young HCC patients. METHODS: A retrospective analysis was performed for HCC patients in our center using Korean cancer registry data. Among 4234 patients enrolled, there were 38 patients younger than 30 years of age (0.9%). We compared clinical characteristics and survival data of these patients (group I) with those of sex-matched, randomly selected HCC patients aged 30-59 years (group II; n = 231) and 60 years or older (group III; n = 147). RESULTS: Group I showed distinct features compared with groups II and III as follows: low frequency of smoking history, high positive rate of hepatitis B s antigen, no association with anti-hepatitis C virus antibody, high frequency of alpha-fetoprotein > or = 400 ng/mL, well-preserved liver function, larger tumor size, more advanced tumor-node-metastasis (TNM) stage and Cancer of the Liver Italian Program (CLIP) score and more frequent application of surgical resection and chemotherapy as initial treatment. The overall survival of group I was worse than that of group II, but similar to that of group III. Multivariate analysis showed that TNM stage and CLIP score, not age itself, were independent predictive factors for survival. CONCLUSIONS: The results suggest that young HCC patients tend to have a poor prognosis owing to advanced tumor stage, despite well-preserved liver function and aggressive treatment. Further studies regarding the role of HCC screening in young people may be useful, especially in hepatitis B virus carriers from high endemic areas.

Adult↗
PubMed2006

[Microsatellite instability in gastric B-cell lymphoma].

BACKGROUND/AIMS: Microsatellite instability (MSI) reflects the defect in DNA mismatch repair (MMR) pathways and plays an important role in certain malignancies. However, the role of MSI in the development of gastric B-cell lymphomas remains unsettled. We aimed to investigate the clinical significance of MSI in patients with gastric B-cell lymphoma. METHODS: Seven micosatellite loci (BAT25, BAT26, D2S123, D5S346, D17S250, D14S50, IGF-IIR) were used for MSI analyses. Microsatellite genotypes were categorized as microsatellite stable (MSS, no positive marker), low frequency MSI (MSI-L,<40% positive marker) and high frequency MSI (MSI-H, >40% positive marker). Among the gastric B-cell lymphoma patients who underwent MSI analysis between September 2002 and May 2003, twenty-two patients were enrolled. Median follow-up duration was 23 months (6-32 months). RESULTS: Median age was 46 years (26-73 years). Male to female ratio was 1:1.4. Twelve patients (54.5%) underwent Helicobacter pylori (H. pylori) eradication and ten patients (45.5%) underwent chemoradiation therapy. No case presented MSI-H. MSI-L was observed in 40.9% (9/22). Between MSS group and MSI-L group, there was no significant difference in age, tumor stage, location, grade of large cell component, H. pylori infection, bulk of tumor and proportion of regression or recurrence. All positive markers belonged to the dinucleotide markers. CONCLUSIONS: The current study suggests that the role of MSI is questionable in the development of gastric B-cell lymphoma due to their low incidence.

Adult↗
PubMed2006

[Peginterferon alfa-2a plus ribavirin for initial treatment of chronic hepatitis C in Korea].

BACKGROUND/AIMS: Combination therapy with peginterferon and ribavirin is a standard therapy for western patients with chronic hepatitis C; however, its efficacy remains unclear in East Asian patients. We evaluated the efficacy and safety of administering peginterferon alfa-2a plus ribavirin in native Korean patients with chronic hepatitis C. METHODS: Seventy-five patients with detectable HCV RNA (52.0% male, median age: 50.8 years) were eligible for the study. The patients were treated with peginterferon alfa-2a 180 mcg/week plus ribavirin 800 mg/day for 24 weeks (for genotype non-1, n=46) or 1000-1200 mg/day for 48 weeks (for genotype 1, n=29). The early virologic response (EVR), the end of treatment virologic response (ETVR), the sustained virologic response (SVR), the biochemical response and the adverse event were analyzed. RESULTS: EVR was seen in 86.2% of the patients with genotype 1. The ETVR was 58.6% in the genotype 1 group and 84.8% in the genotype non-1 group (P=0.02). The overall SVR was 70.7%: 55.2% in the genotype 1 group and 80.4% in the non-1 group (P=0.04). The sustained biochemical response was 64.0%. Multivariate analysis showed that the baseline HCV RNA level (Odds ratio: 0.045, 95% CI: 0.011-0.183, P<0.001) and genotype (Odds ratio: 0.247, 95% CI: 0.063-0.969, P=0.045) had an independent effect on the SVR. Neutropenia, anemia, flu-like symptoms and itching were the common adverse events. Aggravated liver function led to discontinuation of therapy for six patients. Dose modification in twenty-nine patients was effective without producing a significant reduction of the SVR. CONCLUSIONS: Our data suggest that the efficacy of peginterferon plus ribavirin therapy in Koreans is comparable to those from studies on Western patients as an initial treatment for chronic hepatitis C patients. The baseline HCV RNA level and the genotype can be significant factors influencing the SVR.

Adult↗
PubMed2005

Clinicopathologic features and prognosis of combined hepatocellular cholangiocarcinoma.

BACKGROUND: Clinicopathologic features and prognosis of combined hepatocellular cholangiocarcinoma (HCC-CC) have not been established. METHODS: Data of patients who underwent surgical resection for HCC-CC were compared with those of hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (CC) patients. RESULTS: The prevalence of hepatitis B positivity (54.0%) and that of cirrhosis (54.2%) in the HCC-CC group were of intermediate tendency between the HCC group and the CC group. The HCC-CC group presented with a higher prevalence of multiplicity and microvascular emboli and portal vein or hepatic vein invasion, but a lower prevalence of capsular formation compared with the other groups. One- and 3-year survival rates in the HCC-CC group (81.9% and 47.0%, respectively) were lower than those in the HCC group and higher than those in the CC group. The cumulative recurrence rates at 6 months and at 1 year in the HCC-CC group (25.0% and 33.3%, respectively) were higher than those in the HCC group and lower than those in the CC group. CONCLUSIONS: The HCC-CC group has distinct clinicopathologic features compared with the HCC or CC groups. In addition, the HCC-CC group has a prognosis that is better than the CC group but worse than the HCC group.

Adult↗
PubMed2005

Simple devices for dispensing [18F]FDG.

High dose [18F]FDG is prepared routinely using an automated synthesizer. Accordingly, an automated dispenser is needed to dispense [18F]FDG at the desired dose while reducing the operator's radiation exposure, and no dispenser capable of vial-to-vial and vial-to-syringe dispensing in one system is commercially available. Here, we describe simple devices for the vial-to-vial and vial-to-syringe dispensing of [18F]FDG.

Fluorodeoxyglucose F18↗
PubMed2004

Chelation-assisted hydrative dimerization of 1-alkyne forming alpha,beta-enones by an Rh(I) catalyst.

The intermolecular hydrative dimerization of 1-alkyne was developed through the chelation-assisted catalytic system with Rh(I)/2-amino-3-picoline. This novel transformation afforded branched and linear alpha,beta-enones directly from two 1-alkyne molecules and H2O. The results demonstrate that a branch/linear ratio can be controlled by the alkyl substituent of 1-alkyne.

Journal Article↗
PubMed2003

[Mesenchymal hamartoma of the liver in adults].

Mesenchymal hamartoma of the liver (MHL) is a rare benign tumor usually found in childhood, especially during the first two years. MHL is extremely rare in adults. Most reported cases present with a slow growing abdominal mass. It is thought to be a developmental anomaly and consists of bile ducts, hepatocytes and mesenchymal tissue. We report a case of mesenchymal hamartoma of the liver in an adult male with a brief review of the literature.

Adult↗
PubMed2002

Application of Rh(I)-catalyzed C-H bond activation to the ring opening of 2-cycloalkenones in the presence of amines.

[reaction: see text]. Herein described is the application of the Rh(I)-catalyzed C-H bond activation to the ring-opening of 2-cycloalkenones in the presence of cyclohexylamine. This reaction includes the C-C double bond cleavage of 2-cycloalkenones through the conjugate addition of cyclohexylamine followed by the retro-Mannich-type fragmentation. The resulting ring-opened intermediates subsequently underwent either chelation-assisted hydroacylation to afford a ring-opened dicarbonyl compound or beta-alkylation via a ring contraction.

Journal Article↗