Biomedical subjects

Jong Kyun Lee

Publications and source records attributed to Jong Kyun Lee.

13 recordsLinked to original sources

PubMed2026

Malignant epithelial states drive immune dysfunction in ampulla of Vater carcinoma.

BACKGROUND: Ampulla of Vater (AoV) carcinoma is a rare malignancy arising at the junction of intestinal and pancreatobiliary epithelium. Its heterogeneous clinical behavior and histological diversity have hindered therapeutic advances, and the cellular basis of this heterogeneity remains unclear. We aimed to construct a single-cell transcriptomic atlas of AoV carcinoma, with a focus on identifying epithelial subtypes and their interactions with the tumor microenvironment (TME). METHODS: We performed single-cell RNA sequencing on eight primary AoV tumors and four matched normal tissues. Comprehensive clustering and transcriptomic analyses identified cell-type composition, epithelial heterogeneity, and tumor-immune interactions. Findings were validated using deconvolution of bulk RNA-seq data from 62 AoV carcinoma patients. Results Malignant epithelial cells were categorized into four distinct subtypes: Int-Wnt, PB-KRAS, Int-Hypoxia, and Cycling stage. PB-KRAS cells exhibited stem-like transcriptional programs and high genomic instability. Deconvolution analysis of bulk RNA-seq data from the independent AoV cohort revealed that enrichment of the PB-KRAS subtype correlated with tumor recurrence and poor survival. Our immune profiling analysis discovered a significant association between PB-KRAS subtype and GZMK+ CD8+ T cells, which are in a pre-dysfunctional state, alongside SPP1+ macrophages exhibiting immunosuppressive traits. Spatial transcriptome data further supports the immunosuppressive natures of TME around PB-KRAS subtype malignant epithelial cells in AoV carcinoma. CONCLUSIONS: Our study presents a single-cell atlas of AoV carcinoma, highlighting the molecular diversity of malignant epithelium and its association with the immune microenvironment. The PB-KRAS subtype emerges as a stem-like, immunosuppressive tumor state associated with poor prognosis, providing insights for future therapeutic targeting.

Ampulla of Vater carcinoma↗

PubMed2026

Acetate- Versus Lactate-Buffered Crystalloids for Prevention of Post-ERCP Pancreatitis in Patients Without Access to Rectal NSAIDs: A Multicentre Double-Blind Randomized Trial.

BACKGROUND: Aggressive peri-procedural intravenous fluid (IVF) therapy with lactated Ringer's solution (LR) reduces the risk of post-ERCP pancreatitis (PEP), but the standard 8-h protocol is impractical in outpatient settings and the optimal fluid type remains uncertain. We compared LR with an acetate-buffered balanced crystalloid (AC) using a symptom-guided 4-h aggressive IVF protocol. METHODS: This multicentre, double-blind, randomized superiority trial was conducted at three academic hospitals in Korea where rectal NSAIDs are unavailable. Adults with native papillae and moderate-to-high PEP risk were randomized to receive LR or AC. The IVF protocol comprised 10 mL/kg boluses before and after ERCP, followed by 3 mL/kg/h for 4 hours and extended to 8 hours if abdominal pain developed or worsened. The primary outcome was PEP incidence; secondary outcomes included early post-ERCP pain and adverse events. RESULTS: Of 813 patients (404 LR, 409 AC), PEP occurred in 12.4% of the LR group and 11.5% of the AC group (relative risk [RR] 0.93; 95% CI, 0.64-1.35; P = 0.70). Rates of mild (7.9% vs. 7.1%) and moderate (4.5% vs. 4.4%) PEP were similar, and no severe PEP or fluid overload occurred. Among the 68.3% of patients who remained asymptomatic at 4 hours and required only 4-h IVF, PEP occurred in 7.4%, with no cases of severe PEP. CONCLUSION: In this superiority trial, acetate-buffered crystalloid did not reduce PEP compared with lactated Ringer's solution, and no significant safety differences were observed between the two agents. Lactated Ringer's remains the recommended first-line crystalloid for aggressive hydration when rectal NSAIDs are unavailable. TRIAL REGISTRATION: ClinicalTrials.gov (NCT05832047).

Humans↗

PubMed2004

Clinical usefulness of carbohydrate antigen 19-9 as a screening test for pancreatic cancer in an asymptomatic population.

BACKGROUND AND AIM: Although the prognosis for pancreatic cancer is generally poor, it is well known that the survival rate for resected pancreatic cancer is much higher than that for more conservative treatment. The importance of early detection is emphasized for resection of pancreatic cancer. Measurement of serum carbohydrate antigen (CA) 19-9 has shown satisfactory sensitivity and predictive value in symptomatic patients, but no available data has been found on healthy asymptomatic subjects. Thus, the authors aimed to determine the clinical usefulness of CA 19-9 as a screening tool for pancreatic cancer in asymptomatic subjects. METHODS: From December 1994 to November 2000, 70 940 asymptomatic persons visiting the Health Promotion Center at the Samsung Medical Center, Seoul, Korea, participated. All subjects underwent abdominal ultrasonography and serum CA 19-9 measurement. The authors analyzed the sensitivity, specificity, and predictive values of CA 19-9 for detecting pancreatic cancer. Also, those subjects who had a serum CA 19-9 level above the cut-off value were followed up using a serial check of CA 19-9, computed tomography, or endoscopic retrograde cholangiopancreatography. RESULTS: The number of subjects with a level of CA 19-9 above the cutoff of 37 U/mL was 1063 (1.5%), including four cases diagnosed with pancreatic cancer. The prevalence of pancreatic cancer over the age of 30 years is 13.66 per 100 000 population in Korea. Therefore, the sensitivity is 100% and the specificity 98.5%. However, the positive predictive value of CA 19-9 for detecting pancreatic cancer is only 0.9% in the asymptomatic population. CONCLUSION: Mass screening for pancreatic cancer using CA 19-9 levels in asymptomatic subjects is ineffective because of a very low positive predictive value, despite its high sensitivity and specificity.

Biomarkers, Tumor↗

PubMed2003

Evaluation of the post-shunt status with electron beam computed tomography in cyanotic congenital heart disease.

The assessment of the accuracy of Electron Beam Computed Tomography (EBCT) for the follow-up of pulmonary vascular system after the shunt operation in cyanotic congenital heart diseases was purpose of the study. The study group consists of 16 consecutive patients with cyanotic congenital heart disease who had Blalock-Taussig (BT) shunt (n=7), bi- directional cavo-pulmonary shunt (BCPS, n=7) and unifocalization (n=2). EBT images were obtained on systolic phase under EKG gating and after intravenous administration of contrast agent. We evaluated the shunt patency, anatomy of intrapericardial pulmonary artery, parenchymal pulmonary vessels and background lung attenuation for the pulmonary blood flow, and the presence of systemic arterial and venous collaterals. Angiography (n=12) and echocardiography (n=16) were used as the gold standards. EBCT was consistent with angiogram in detecting the shunt patency and in depicting the anatomy of the intrapericardial pulmonary artery. Occlusion of the BT shunts was not detected in 2 patients by echocardiography. Diffuse or focally decreased pulmonary flow on EBCT in 8 patients was consistent with the pulmonary hemodynamics pattern revealed by cardiac catheterization. Uneven attenuation between lobes was related with multifocal supply of pulmonary flow or occlusion of lobar pulmonary arteries. Systemic collateral arteries were observed in 5 at the corresponding site of the decreased pulmonary flow. Systemic venous collaterals seen in all patients following BCPS were eventually draining to the inferior vena cava in 5 and to the left atrium in 2. EBCT provided accurate information of the pulmonary vascular system after shunt and has unique advantage over echocardiography in assessing patency of BT shunt or unifocalization tubes within the pleural space, the estimation of regional difference in pulmonary hemodynamics, and the detection of systemic collateral vessels. Therefore EBCT may provide useful information about the timing of definitive correction and the need for a second shunt or an interventional procedure prior to total repair.

Child↗

PubMed2003

A large fibrous polyp of the gallbladder mimicking a polypoid carcinoma.

Fibrous polyp of the gallbladder is a rare variant of benign gallbladder polyp. Differentiation between a benign polyp and polypoid carcinoma of the gallbladder is often difficult when the polyp is more than 1 cm in diameter. We report a rare case of a large fibrous polyp of the gallbladder mimicking a carcinoma. A 44-year-old Korean woman who presented with abdominal pain was diagnosed with a large gallbladder polyp, measuring 1.26 cm in diameter, by abdominal ultrasonography. The lesion was echogenic with a nodular surface on ultrasonography, and showed contrast enhancement on computed tomography. Neither evidence of infiltration into the gallbladder wall nor lymph node enlargement was shown. The resected gallbladder showed a 1.2 x 0.8-cm-sized polyp with a nodular surface. Histologically, it showed a leaf-like configuration and loose or cellular connective stroma containing scattered duct-like structures, varying-sized vessels, and patchy infiltration of chronic inflammatory cells. Stromal cells were immunoreactive for vimentin and smooth-muscle actin and negative for S-100 protein and desmin. Large fibrous polyps of the gallbladder should be considered in the differential diagnosis of benign and malignant polypoid lesions of the gallbladder.

Adult↗

PubMed2003

Effect of 0.2 percent glyceryl trinitrate ointment on wound healing after a hemorrhoidectomy: results of a randomized, prospective, double-blind, placebo-controlled trial.

PURPOSE: Glyceryl trinitrate ointment acts as a dilator of the internal anal sphincter. It has been used as a treatment modality that replaces the lateral sphincterotomy in chronic anal fissures. When glyceryl trinitrate ointment is applied to the wound from a hemorrhoidectomy, it is thought that it will shorten the healing time and decrease postoperative pain. Our study focused on the efficacy of using 0.2 percent glyceryl trinitrate ointment to shorten the healing time after a hemorrhoidectomy. METHODS: A randomized, prospective, double-blind, and placebo-controlled study was designed. The power test indicated that 55 patients should be in each group to give a 90 percent chance of finding a 30 percent difference in healing time. The selection criteria for inclusion in this study were patients with third-degree or fourth-degree hemorrhoids and patients undergoing hemorrhoidectomies for three or more piles. From November 2000 to July 2001, the first 110 patients to meet our criteria were selected, 55 in the nitroglycerin group and 55 in the placebo group. The same physician performed all of the hemorrhoidectomies, and intravenous patient-controlled analgesia was not used. Cases involving other procedures for fissures or fistulas were excluded. The patients randomly received glyceryl trinitrate and placebo ointments from the pharmacologist. The pain score was checked using a visual analog scale (minimum = 0, maximum = 10) during the hospital stay, and complete wound healing was checked at three weeks after the operation. Demands for analgesics and the frequency of postoperative complications were recorded. RESULTS: When the trial was completed, 49 patients remained in the nitroglycerin group and 53 patients in the placebo group. No significant differences in the gender and the age distributions, the number of excised piles, the time for the procedures, the length of hospital stay, and the consumed amounts of analgesics existed between the two groups. The pain score in the nitroglycerin group showed a significant difference with the repeated measures analysis (P < 0.001). The wound healing rates at three weeks postoperative were 74.5 percent in the nitroglycerin group and 42 percent in the placebo group (P = 0.002). There was no significant increase in complications in the nitroglycerin group. CONCLUSION: More rapid healing of hemorrhoidectomy wounds without any specific complications was effected by 0.2 percent glyceryl trinitrate ointment.

Administration, Topical↗

PubMed2003

Patency of cavopulmonary connection studied by single phase electron beam computed tomography.

PURPOSE: The shunt patency and anatomic alteration of central PA after cavopulmonary connection was assessed by one phase electron-beam computed tomography (EBCT) METHODS: Thirteen patients that received a bi-directional cavo-pulmonary shunt (BCPS, n = 7) or total cavo-pulmonary connection (TCPC, n = 6) were included. The patency of the shunt and the anatomy of intra-pericardial PA were evaluated by EBCT, and compared by angiography and echocardiography. RESULTS: EBCT accurately evaluated shunt patency and the anatomy of the intra-pericardial PA, except for the incorrect diagnosis of SVC-PA shunt patency and peripheral pulmonary stenosis in two TCPC patients. Both of these patients had bilateral SVC and received either bilateral BCPS or ligation of the left SVC respectively. The baffle between the IVC and PA was partly opacified through a fenestration of the baffle, but was not opacified in two patients without fenestration. CONCLUSION: EBCT accurately evaluated shunt patency and the anatomy of central PA, however, the accuracy was limited in two cases with bilateral SVC. The opacification of the intra-atrial baffle was insufficient in TCPC cases. Multi-phase CT angiography may overcome this limitation in this patient subset.

Cardiac Catheterization↗

PubMed2003

Differential diagnosis of intrahepatic bile duct dilatation without demonstrable mass on ultrasonography or CT: benign versus malignancy.

BACKGROUND: The purpose of the present study was to define the differential diagnostic markers of benign and malignant bile duct strictures without demonstrable mass on ultrasonography (US) or computed tomography (CT) using aspects of clinical, laboratory and imaging findings. METHODS: Between February 1995 and February 2001, 24 patients who underwent surgical resection for dilations of the bile duct (peripheral and hilar) without visible mass lesion on US or CT were included in our study. Hospital records, laboratory results, findings of imaging studies and pathological findings were reviewed retrospectively. RESULTS: For laboratory results, levels of alkaline phosphatase (benign 163.9 +/- 145.1 vs malignant 407.25 +/- 481.7; p < 0.05) and CA 19-9 (benign 25.0 +/- 41.1 vs malignant 614.6 +/- 818.5; p < 0.05) levels were significantly elevated in the malignant group compared with that of the benign group. Findings such as thickening of the bile duct wall >/= 5 mm (P < 0.05) on radiological examination, significant regional lymph node enlargement (> 1 cm, p = 0.01) on CT scan and abrupt cut-off (P < 0.01), and separation of bile ducts (P < 0.05) on cholangiogram were differential diagnostic markers between the two groups. CONCLUSIONS: Preoperative laboratory data such as alkaline phosphatase and CA 19-9, and imaging findings such as significant wall thickening and regional lymph node enlargement on CT, abrupt cut-off and separation of bile duct on cholangiogram are useful differential diagnostic markers for benign and malignant bile duct strictures without demonstrable mass on US or CT.

Adult↗

PubMed2003

Expression of cyclooxygenase-2 and its correlation with clinicopathologic factors of ampulla of vater cancer.

There has been no report for the expression of cyclooxygenase-2 (COX-2) and its clinicopathologic and biologic significance in ampulla of Vater cancer. This study was aimed for the clarification of COX-2 expression and its biologic roles in ampulla of Vater cancer. Fourty-six patients with ampulla of Vater cancer were enrolled and their COX-2 expression and clinicopathologic features were analyzed. The median age of patients was 60 yr and the mean duration of follow-up was 35 months (range: 14-82 months). Immunohistochemical stainings for COX-2, Ki-67, CD34 and TUNEL staining were performed. The immunoreactive COX-2 expression was present in 24 (52.2%) patients of ampulla of Vater cancer and mainly localized in cytosolic and perinuclear region. There was no significant difference in the length of survival between COX-2 postive and negative group (p=0.9420 by Log Rank test). Also, there were no significant differences of proliferation index (p=0.326), apoptotic index (p=0.764) and microvessel density (p=0.135) between COX-2 positive and negative group. Initial pTNM stage (p=0.0028 by Log Rank test) and blood transfusion over 4 pints during operation (p=0.0254 by Log Rank test) were independent prognostic factor in patients with ampulla of Vater cancer. It is suggested that immunoreactivity of COX-2 is not correlated with clinicopathologic and biologic features of ampulla of Vater cancer.

Adult↗

PubMed2003

[A case of serous cystadenoma of the pancreas communicating with the pancreatic duct].

Serous cystadenoma of the pancreas is a rare disease and is usually benign. Mucinous cystadenoma, another cystic neoplasm of the pancreas, has a malignant potential. Serous cystadenoma is usually composed of many small cysts lined by small, cuboidal or flattened cells containing abundant glycogen. With the finding of endoscopic retrograde pancreatography, a communication between the cyst and pancreatic duct is observed occasionally in the mucinous cystadenoma, but rarely in the case of serous cystadenoma of the pancreas. We experienced a case of serous cystadenoma of the pancreas that had a communication between a cyst and the pancreatic duct.

Adult↗

PubMed2002

Role of cyclooxygenase-2 and inducible nitric oxide synthase in pancreatic cancer.

BACKGROUND AND AIM: Recently, it has been recognized that both cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) produce important endogenous factors of human tumor progression. However, the clinicopathological and biological significance of the expression of COX-2 and iNOS in pancreatic cancer remains unclear. The objective of this study is to find the possible roles and clinical significance of COX-2 and iNOS expression in pancreatic cancer. METHODS: Seventy-two pancreatic adenocarcinoma tissue specimens were obtained through surgical resection. We investigated the immunohistochemical expression of COX-2 and iNOS in respect to variable clinicopathological characteristics, proliferation activity (by Ki-67 expression), apoptosis (by terminal deoxyribonucleotidyl transferase-mediated dUTP nick-end labeling stain), and microvessel density (by CD34 expression; angiogenesis). RESULTS: Immunohistochemical investigations demonstrated immunolabeling of tumor cells with the primary antibodies, bovine anti-iNOS and anti-COX-2 antibodies. The COX-2 and iNOS positive rates were 41.7 and 66.7%, respectively. There was significant correlation between positive COX-2 and positive iNOS expression (P = 0.043). The proliferation index (Ki-67 labeling index) was higher in COX-2 positive specimens compared to COX-2 negative specimen (P = 0.015). The apoptotic index of positive iNOS expressions was significantly higher than negative expressions (P < 0.001). The expression of COX-2 and iNOS proteins did not correlate with age, sex, serum bilirubin, CA-19-9, location, size, American Joint Committee on Cancer stage, differentiation, distant metastasis, patient survival, or microvessel density. CONCLUSIONS: Although the pattern of positive expression was similar in both enzymes, the effect on tumor progression differed; iNOS expression may play a role in apoptosis of tumor cell, while COX-2 expression may contribute to tumor proliferation. However, COX-2 and iNOS expression is not related to prognosis in patients with pancreatic cancer.

Adenocarcinoma↗

PubMed2002

Clinical significance of depressed-type colorectal neoplasms based on growth and development.

A route of colorectal cancer development other than the adenoma-carcinoma sequence has recently become an issue due to the discovery of depressed-type early colorectal cancers. Moreover, the fact that some polyp-like cancers actually originate from depressed-type lesions has become obvious. Despite the protruding shapes of depressed-type early colorectal cancers, they probably have biological characteristics, which are different from those of the usual polyp lesions. We undertook this study to evaluate the clinical significance of depressed-type colorectal neoplasms. The authors recently experienced 87 cases of depressed-type colorectal neoplasms. Using Kudo's classification, we classified these 87 cases into three types based on their growth patterns, type IIc, type IIa + IIc, and type Is + IIc, and then analyzed these types on the basis of size, type, and submucosal invasion rate. The submucosal invasion rate of cancers of type IIa + IIc was significantly higher than that of type IIc (p < 0.05), and the rate for cancers of types IIa + IIc and Is + IIc together was significantly higher than that of type IIc (p < 0.05). However, no significant difference was found between the rates of types IIa + IIc and Is + IIc. In conclusion, the IIa + IIc and Is + IIc sub-types of depressed-type colorectal neoplasms, individually and together, have higher rates of submucosal invasion than type IIc lesions. Accordingly, type IIa + IIc and type Is + IIc must be differentiated from the usual polyps and should be managed cautiously, despite their protruding shapes.

Colorectal Neoplasms↗

PubMedDate not supplied

Papillary neoplasms of the bile duct that mimic biliary stone disease.

Papillary tumors of the bile duct are intraductal tumors with innumerable minute, frondlike papillary projections. These tumors may be either fixed to or detached from the bile duct wall. However, because the papillary projections on the surface of papillary tumors are long and slender, the tumors are friable and slough easily. The sloughed tumor fragments may float within the bile ducts, resulting in intermittent partial biliary obstruction and mimicking bile duct stones at clinical examination and at ultrasonography (US), computed tomography (CT), and cholangiography. A tumor manifests radiologically as thickening and irregularity of the bile duct wall or as a fixed or sloughed intraductal mass. A nonshadowing intraductal echogenic cast seen at US, an intraductal noncalcified soft-tissue mass with asymmetric wall thickening seen at CT, and an intraductal mass with a papillary surface and a serrated bile duct margin seen at cholangiography are all appearances that suggest a papillary tumor and may be helpful in differentiating a tumor from a bile duct stone.

Adenocarcinoma, Papillary↗