Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
32
result(s) for
"Kwak, Jung-Myun"
Sort by:
Anus-Preserving Surgery in Advanced Low-Lying Rectal Cancer: A Perspective on Oncological Safety of Intersphincteric Resection
2021
The surgical management of low-lying rectal cancer, within 5 cm from the anal verge (AV), is challenging due to the possibility, or not, to preserve the anus with its sphincter muscles maintaining oncological safety. The standardization of total mesorectal excision, the adoption of neoadjuvant chemoradiotherapy, the implementation of rectal magnetic resonance imaging, and the evolution of mechanical staplers have increased the rate of anus-preserving surgeries. Moreover, extensive anatomy and physiology studies have increased the understanding of the complexity of the deep pelvis. Intersphincteric resection (ISR) was introduced nearly three decades ago as the ultimate anus-preserving surgery. The definition and indication of ISR have changed over time. The adoption of the robotic platform provides excellent perioperative results with no differences in oncological outcomes. Pushing the boundaries of anus-preserving surgeries has risen doubts on oncological safety in order to preserve function. This review critically discusses the oncological safety of ISR by evaluating the anatomical characteristics of the deep pelvis, the clinical indications, the role of distal and circumferential resection margins, the role of the neoadjuvant chemoradiotherapy, the outcomes between surgical approaches (open, laparoscopic, and robotic), the comparison with abdominoperineal resection, the risk factors for oncological outcomes and local recurrence, the patterns of local recurrences after ISR, considerations on functional outcomes after ISR, and learning curve and surgical education on ISR.
Journal Article
Recurrence Patterns and Risk Factors after Curative Resection for Colorectal Cancer: Insights for Postoperative Surveillance Strategies
2023
This study aimed to assess recurrence patterns and related risk factors following curative resection of colorectal cancer (CRC). This retrospective observational study was conducted at a tertiary care center, including 2622 patients with stage I–III CRC who underwent curative resection between 2008 and 2018. Hazard rates of recurrence were calculated using a hazard function. The primary outcome was the peak recurrence time after curative resection and secondary outcomes were prognostic factors associated with recurrence. Over a median follow-up period of 53 months, the overall, locoregional and systemic recurrence rates were 8.9%, 0.7%, and 8.5%, respectively. Recurrence rates were significantly higher for rectal cancer (14.9% overall, 4.4% locoregionally, and 12.3% systemically) than for colon cancer (all p < 0.001). The peak recurrence time was 11 months, with variations in hazard rates and curves depending on the tumor location, stage, and risk factors. Patients with AL or CRM involvement exhibited a distinct pattern, with a high hazard rate in the early postoperative period. Understanding these recurrence patterns and risk factors is crucial for establishing effective postoperative surveillance strategies. Our findings suggested that short-interval surveillance should be considered during the first 2 years post-surgery, particularly for high-risk patients who should receive early attention.
Journal Article
Noninvasive Diagnosis and Evaluation of Curative Surgery for Gastric Cancer by Using NMR-based Metabolomic Profiling
by
Kwak, Jung-Myun
,
Park, Sungsoo
,
Cho, Sung-il
in
Alanine - urine
,
Area Under Curve
,
Arginine - urine
2014
Background
Mass screening for gastric cancer (GC), particularly using endoscopy, may not be the most practical approach as a result of its high cost, lack of acceptance, and poor availability. Thus, novel markers that can be used in cost-effective diagnosis and noninvasive screening for GC are needed.
Methods
A total of 154 urine samples from GC patients and healthy individuals and 30 pairs of matched tumor and normal stomach tissues were collected. Multivariate analysis was performed on urinary and tissue metabolic profiles acquired using
1
H nuclear magnetic resonance and
1
H high-resolution magic angle spinning spectroscopy, respectively. In addition, metabolic profiling of urine from GC patients after curative surgery was performed.
Results
Multivariate statistical analysis showed significant separation in the urinary and tissue data of GC patients and healthy individuals. The metabolites altered in the urine of GC patients were related to amino acid and lipid metabolism, consistent with changes in GC tissue. In the external validation, the presence of GC (early or advanced) from the urine model was predicted with high accuracy, which showed much higher sensitivity than carbohydrate antigen 19-9 and carcinoembryonic antigen. Furthermore, 4-hydroxyphenylacetate, alanine, phenylacetylglycine, mannitol, glycolate, and arginine levels were significantly correlated with cancer T stage and, together with hypoxanthine level, showed a recovery tendency toward healthy controls in the postoperative samples compared to the preoperative samples.
Conclusions
An urinary metabolomics approach may be useful for the effective diagnosis of GC.
Journal Article
Midline incision vs. transverse incision for specimen extraction is not a significant risk factor for developing incisional hernia after minimally invasive colorectal surgery: multivariable analysis of a large cohort from a single tertiary center in Korea
2022
BackgroundIncisional hernia (IH) is a commonly encountered problem even in the era of minimally invasive surgery (MIS). Numerous studies on IH are available in English literature, but there are lack of data from the Eastern part of the world. This study aimed to evaluate the risk factors as well as incidence of IH by analyzing a large cohort collected from a single tertiary center in Korea.MethodsAmong a total number of 4276 colorectal cancer patients who underwent a surgical resection from 2006 to 2019 in Korea University Anam Hospital, 2704 patients (2200 laparoscopic and 504 robotic) who met the inclusion criteria were analyzed. IH was confirmed by each patient’s diagnosis code registered in the hospital databank based on physical examination and/or computed tomography findings. Clinical data including specimen extraction incision (transverse or vertical midline) were compared between IH group and no IH group. Risk factors of developing IH were assessed by utilizing univariable and multivariable analyses.ResultsDuring the median follow-up of 41 months, 73 patients (2.7%) developed IH. Midline incision group (n = 1472) had a higher incidence of IH than that of transverse incision group (n = 1232) (3.5% vs. 1.7%, p = 0.003). The univariable analysis revealed that the risk factors of developing IH were old age, female gender, obesity, co-morbid cardiovascular disease, transverse incision for specimen extraction, and perioperative bleeding requiring transfusion. However, on multivariable analysis, specimen extraction site was not significant in developing IH and transfusion requirement was the strongest risk factor.ConclusionsIH development after MIS is uncommon in Korean patients. Multivariable analysis suggests that specimen extraction site can be flexibly chosen between midline and transverse incisions, with little concern about risk of developing IH. Careful efforts are required to minimize operative bleeding because blood transfusion is a strong risk factor for developing IH.
Journal Article
Modular laser-based endoluminal ablation of the gastrointestinal tract: in vivo dose–effect evaluation and predictive numerical model
2019
BackgroundEndoscopic submucosal dissection allows for “en bloc” removal of early gastrointestinal neoplasms. However, it is technically demanding and time-consuming. Alternatives could rely on energy-based techniques. We aimed to evaluate a predictive numerical model of thermal damage to preoperatively define optimal laser settings allowing for a controlled ablation down to the submucosa, and the ability of confocal endomicroscopy to provide damage information.Materials and methodsA Nd:YAG laser was applied onto the gastric mucosa of 21 Wistar rats on 10 spots (total 210). Power settings ranging from 0.5 to 2.5W were applied during 1–12 s, with a consequent energy delivery varying from 0.5 to 30 J. Out of the 210 samples, a total of 1050 hematoxilin–eosin stained slides were obtained. To evaluate thermal injury, the ratio between the damage depth (DD) over the mucosa and the submucosa thickness (T) was calculated. Effective and safe ablation was considered for a DD/T ratio ≤ 1 (only mucosal and submucosal damage). Confocal endomicroscopy was performed before and after ablation. A numerical model, using human physical properties, was developed to predict thermal damage.ResultsNo full-thickness perforations were detected. On histology, the DD/T ratio at 0.5 J was 0.57 ± 0.21, significantly lower when compared to energies ranging from 15 J (a DD/T ratio = 1.2 ± 0.3; p < 0.001) until 30 J (a DD/T ratio = 1.33 ± 0.31; p < 0.001). Safe mucosal and submucosal ablations were achieved applying energy between 4 and 12 J, never impairing the muscularis propria. Confocal endomicroscopy showed a distorted gland architecture. The predicted damage depth demonstrated a significant positive linear correlation with the experimental data (Pearson’s r 0.85; 95% CI 0.66–0.94).ConclusionsLow-power settings achieved effective and safe mucosal and submucosal ablation. The numerical model allowed for an accurate prediction of the ablated layers. Confocal endomicroscopy provided real-time thermal damage visualization. Further studies on larger animal models are required.
Journal Article
Effectiveness of personalized treatment stage-adjusted digital therapeutics in colorectal cancer: a randomized controlled trial
by
Kim, Sun Woo
,
Kwak, Jung-Myun
,
Lim, Ji Young
in
Biomedical and Life Sciences
,
Biomedicine
,
Body fat
2023
Background
Colorectal cancer survivors often experience decline in physical performance and poor quality of life after surgery and during adjuvant therapies. In these patients, preserving skeletal muscle mass and high-quality nourishment are essential to reduce postoperative complications and improve quality of life and cancer-specific survival. Digital therapeutics have emerged as an encouraging tool for cancer survivors. However, to the best of our knowledge, randomized clinical trials applying personalized mobile application and smart bands as a supportive tool to several colorectal patients remain to be conducted, intervening immediately after the surgical treatment.
Methods
This study is a prospective, multi-center, single-blinded, two-armed, randomized controlled trial. The study aims to recruit 324 patients from three hospitals. Patients will be randomly allocated to two groups for one year of rehabilitation, starting immediately after the operation: a digital healthcare system rehabilitation (intervention) group and a conventional education-based rehabilitation (control) group. The primary objective of this protocol is to clarify the effect of digital healthcare system rehabilitation on skeletal muscle mass increment in patients with colorectal cancer. The secondary outcomes would be the improvement in quality of life measured by EORTC QLQ C30 and CR29, enhanced physical fitness level measured by grip strength test, 30-sec chair stand test and 2-min walk test, increased physical activity measured by IPAQ-SF, alleviated pain intensity, decreased severity of the LARS, weight, and fat mass. These measurements will be held on enrollment and at 1, 3, 6 and 12 months thereafter.
Discussion
This study will compare the effect of personalized treatment stage-adjusted digital health interventions on immediate postoperative rehabilitation with that of conventional education-based rehabilitation in patients with colorectal cancer. This will be the first randomized clinical trial performing immediate postoperative rehabilitation in a large number of patients with colorectal cancer with a tailored digital health intervention, modified according to the treatment phase and patient condition. The study will add foundations for the application of comprehensive digital healthcare programs focusing on individuality in postoperative rehabilitation of patients with cancer.
Trial registration
NCT05046756. Registered on 11 May 2021.
Journal Article
Mixed reality navigation system for ultrasound-guided percutaneous punctures: a pre-clinical evaluation
by
Guinin Maxime
,
Marescaux Jacques
,
González, Cristians A
in
Endoscopy
,
Feasibility studies
,
Glycerol
2020
Image-guided surgery is growing in importance with each year. Various imaging technologies are used. The objective of this study was to test whether a new mixed reality navigation system (MRNS) improved percutaneous punctures. This system allowed to clearly visualize the needle tip, needle orientation, US probe and puncture target simultaneously with an interactive 3D computer user inferface. Prospective pre-clinical comparative study. An opaque ballistic gel phantom containing grapes of different sizes was used to simulate puncture targets. The evaluation consisted of ultrasound-guided (US-guided) needle punctures divided into two groups, standard group consisted of punctures using the standard approach (US-guided), and assisted navigation group consisted of punctures using MRNS. Once a puncture was completed, a computed tomography scan was made of the phantom and needle. The distance between the needle tip and the center of the target was measured. The time required to complete the puncture and puncture attempts was also calculated. Total participants was n = 23, between surgeons, medical technicians and radiologist. The participants were divided into novices (without experience, 69.6%) and experienced (with experience > 25 procedures, 30.4%). Each participant performed the puncture of six targets. For puncture completion time, the assisted navigation group was faster (42.1%) compared to the standard group (57.9%) (28.3 s ± 24.7 vs. 39.3 s ± 46.3—p 0.775). The total punctures attempts was lower in the assisted navigation group (35.4%) compared to the standard group (64.6%) (1.0 mm ± 0.2 vs. 1.8 mm ± 1.1—p 0.000). The assisted navigation group was more accurate than the standard group (4.2 ± 2.9 vs. 6.5 ± 4.7—p 0.003), observed in both novices and experienced groups. The use of MRNS improved ultrasound-guided percutaneous punctures parameters compared to the standard approach.
Journal Article
Hybrid endoluminal stapled pyloroplasty: an alternative treatment option for gastric outlet obstruction syndrome
2019
BackgroundGastroparesis is a rapidly increasing problem with sometimes devastating consequences. While surgical treatments, particularly laparoscopic pyloroplasty, have recently gained popularity, they require general anesthesia, advanced skills, and can lead to leaks. Peroral pyloromyotomy is a less invasive alternative; however, this technique is technically demanding and not widely available. We describe a hybrid laparo-endoscopic collaborative approach using a novel gastric access device to allow endoluminal stapled pyloroplasty as an alternative treatment option for gastric outlet obstruction.MethodsUnder general anesthesia, six pigs (mean weight 33 kg) underwent endoscopic placement of intragastric ports using a technique similar to percutaneous endoscopic gastrostomy. A 5 mm laparoscope was used for visualization. A functional lumen imagine probe was used to measure the cross-sectional area (CSA) and diameter of the pylorus before, after, and at 1 week after intervention. Pyloroplasty was performed using a 5 mm articulating laparoscopic stapler. Gastrotomies were closed by endoscopic clips, endoscopic suture, or combination. After 6–8 days, a second evaluation was performed. At the end of the protocol, all animals were euthanized.ResultsSix pyloroplasties were performed. In all cases, this technique was effective in achieving significant pyloric dilatation. The median pre-pyloroplasty pyloric diameter (D) and cross-sectional area (CSA) were 8 mm (4.9–11.6 mm) and 58.6 mm2 (19–107 mm2), respectively. After the procedure, these values increased to 13.41 mm (9.8–17.6 mm) and 147.7 mm2 (76–244 mm2), respectively (p = 0.0152). No important intraoperative events were observed. Postoperatively, all animals did well, with adequate oral intake and no relevant complications. At follow-up endoscopy, all incisions were healed and the pylorus widely patent.ConclusionsHybrid endoluminal stapled pyloroplasty is a feasible, safe, and effective alternative method for the treatment of gastric outlet obstruction syndrome.
Journal Article
Incidence and risk factors of chylous ascites after colorectal cancer surgery
2013
The aim of this study was to identify possible risk factors associated with chylous ascites after colorectal cancer surgery.
Patients who underwent colorectal cancer resection were enrolled in this study. Data were compared between patients who developed chylous ascites and those who did not.
Chylous ascites was detected in 48 (6.6%) patients. There were significant differences between the groups with and without chylous ascites in terms of age (65.6 vs 61.6 years, P = .017), operator (5.0% vs 15.5%, P < .001), operative procedure based on tumor location (P = .041), operative time (206.0 vs 229.8 minutes, P = .045), and blood loss (78.1 vs 219.7 mL, P = .036). After subgroup analysis for right-sided colectomy and low anterior resection to compensate for the effects of the operative procedure, the differences in the operative time and blood loss were not significant. In most patients, chylous ascites was resolved with conservative management.
Chylous ascites developed significantly more frequently in patients who underwent right-sided colectomy and in elderly patients. In addition, the incidence was also dependent on the operator. Conservative treatment was effective in most patients.
Journal Article
Accuracy of MRI for predicting anterior peritoneal reflection involvement in locally advanced rectal cancer: a comparison with operative findings
2022
PurposeTo assess the diagnostic accuracy of preoperative rectal MRI for anterior peritoneal reflection (APR) involvement in rectal cancer through comparison with the surgeon’s operative findings.MethodsThis retrospective study was approved by the institutional review board; informed consent was waived. We enrolled 55 consecutive patients with suspected locally advanced mid-to-upper rectal cancer. All patients underwent rectal MRI using a 3T system. APR involvement in rectal cancer was assessed radiologically using a 5-point scale by two independent board-certified abdominal radiologists. The surgeon’s evaluation during surgery was regarded as the gold standard for APR involvement. The accuracy of rectal MRI in predicting APR involvement was obtained.ResultsRectal MRI showed good APR identification (rater 1, 92.7%; rater 2, 94.7%). On preoperative rectal MRI, rater 1 diagnosed 19 (34.5%) patients as having APR involvement and rater 2 diagnosed 28 (50.9%) as having APR involvement. There was moderate agreement (κ = 0.602, p < 0.001) between the two raters with regard to the evaluation of APR involvement. During surgery, the surgeon confirmed APR involvement in 13 (23.6%) patients. The sensitivity, specificity, PPV, and NPV of preoperative MRI for APR involvement were 69.2%, 76.2%, 47.4%, and 88.9%, respectively. The diagnostic accuracy of MRI for predicting APR involvement was 74.6%.ConclusionPreoperative rectal MRI provides accurate anatomical information regarding APR involvement with high conspicuity. However, MRI has relatively low sensitivity (< 70%) and a low PPV (< 50%) with regard to the assessment of APR involvement in rectal tumors. Both rater 1 and rater 2 evaluated these images as positive involvement of APR. The patient underwent laparoscopic low anterior resection after preoperative evaluation. However, during surgery, the surgeon evaluated APR involvement as negative, and the final pathologic staging was confirmed as T3.
Journal Article