1.Gut Microbiome and Colorectal Cancer
The Korean Journal of Gastroenterology 2023;82(2):56-62
Colorectal cancer (CRC) is one of the most common cancers in Korea. A majority of CRCs are caused by progressive genomic alterations referred to as the adenoma-carcinoma sequence. The factors that may increase the risk of CRC include obesity and consumption of a high-fat diet, red meat, processed meat, and alcohol. Recently, the role of gut microbiota in the formation, progression and treatment of CRCs has been investigated in depth. An altered gut microbiota can drive carcinogenesis and cause the development of CRC.Studies have also shown the role of gut microbiota in the prevention of CRC and the impact of therapies involving gut microbiota on CRC. Herein, we summarize the current understanding of the role of the gut microbiota in the development of CRC and its therapeutic potential, including the prevention of CRC and in enhancing efficacy of chemotherapy and immunotherapy.
3.Next Generation Fecal Microbiota Transplantation
Clinical Endoscopy 2021;54(2):152-156
Fecal microbiota transplantation (FMT) is considered as an effective treatment for Clostridioides difficile infection. However, the precise mechanism of FMT is yet to be determined. Human stool consists of the gut microbiota, bacterial debris, and metabolic products. Of these, the intestinal microbiota is the most important factor that exerts therapeutic efficacy in FMT. Fresh donor stool, blended with normal saline, has been employed for traditional FMT. Nevertheless, stool processing is a major impediment in FMT. Frozen stool and capsule formulations have similar efficacy to that of fresh stool. In addition, several novel stool products have been identified. A stool bank that provides stool products with pre-screened donor stool has been established to help physicians and thereby facilitate FMT. Recent next-generation sequencing techniques have been key in facilitating the detailed analysis of the microbiota and gut environment of individual donors and recipients.
4.Next Generation Fecal Microbiota Transplantation
Clinical Endoscopy 2021;54(2):152-156
Fecal microbiota transplantation (FMT) is considered as an effective treatment for Clostridioides difficile infection. However, the precise mechanism of FMT is yet to be determined. Human stool consists of the gut microbiota, bacterial debris, and metabolic products. Of these, the intestinal microbiota is the most important factor that exerts therapeutic efficacy in FMT. Fresh donor stool, blended with normal saline, has been employed for traditional FMT. Nevertheless, stool processing is a major impediment in FMT. Frozen stool and capsule formulations have similar efficacy to that of fresh stool. In addition, several novel stool products have been identified. A stool bank that provides stool products with pre-screened donor stool has been established to help physicians and thereby facilitate FMT. Recent next-generation sequencing techniques have been key in facilitating the detailed analysis of the microbiota and gut environment of individual donors and recipients.
5.Management of complications related to colorectal endoscopic submucosal dissection
Tae-Geun GWEON ; Dong-Hoon YANG
Clinical Endoscopy 2023;56(4):423-432
Compared to endoscopic mucosal resection (EMR), colonoscopic endoscopic submucosal dissection (C-ESD) has the advantages of higher en bloc resection rates and lower recurrence rates of colorectal neoplasms. Therefore, C-ESD is considered an effective treatment method for laterally spread tumors and early colorectal cancer. However, C-ESD is technically more difficult and requires a longer procedure time than EMR. In addition to therapeutic efficacy and procedural difficulty, safety concerns should always be considered when performing C-ESD in clinical practice. Bleeding and perforation are the main adverse events associated with C-ESD and can occur during C-ESD or after the completion of the procedure. Most bleeding associated with C-ESD can be managed endoscopically, even if it occurs during or after the procedure. More recently, most perforations identified during C-ESD can also be managed endoscopically, unless the mural defect is too large to be sutured with endoscopic devices or the patient is hemodynamically unstable. Delayed perforations are quite rare, but they require surgical treatment more frequently than endoscopically identified intraprocedural perforations or radiologically identified immediate postprocedural perforations. Post-ESD coagulation syndrome is a relatively underestimated adverse event, which can mimic localized peritonitis from perforation. Here, we classify and characterize the complications associated with C-ESD and recommend management options for them.
7.Postgastrectomy gastric cancer patients are at high risk for colorectal neoplasia: a case control study
Tae-Geun GWEON ; Kyu-Tae YOON ; Chang Hyun KIM ; Jin-Jo KIM
Intestinal Research 2021;19(2):239-246
Background/Aims:
Several studies have shown that colorectal neoplasms (CRN) including colorectal cancer (CRC) may be prevalent in patients with gastric cancer. However, in most of these studies, colonoscopy to investigate the prevalence of CRN was performed prior to surgery. We aimed to investigate whether CRN was more prevalent in postgastrectomy gastric cancer patients than in healthy individuals.
Methods:
We reviewed the medical records of those patients within a cohort of gastric cancer patients with gastrectomy who underwent colonoscopy between 2016 and 2017. Controls age- and sex-matched with gastric cancer patients at a 2:1 ratio were identified among those who underwent colonoscopy at a health-promotion center. The frequencies of CRN, advanced CRN (ACRN), and CRC among patients with gastrectomy were compared with those in the control subjects. A total of 744 individuals (gastric cancer, 248; control, 496) were included.
Results:
The rates of CRN and ACRN in the gastric cancer group were higher than those in the healthy individuals (CRN, 47.6% vs. 34.7%, P< 0.001; ACRN, 16.9% vs. 10.9%, P= 0.020). The rate of CRC was comparable between the 2 groups (2.0% vs. 0.6%, P= 0.125). Multivariate analysis identified previous gastrectomy for gastric cancer and male sex as significant risk factors for (A)CRN.
Conclusions
CRN and ACRN were more prevalent in patients who underwent surgery for gastric cancer than in the control group. Regular surveillance colonoscopy at appropriate intervals is indicated after gastrectomy.
8.Postgastrectomy gastric cancer patients are at high risk for colorectal neoplasia: a case control study
Tae-Geun GWEON ; Kyu-Tae YOON ; Chang Hyun KIM ; Jin-Jo KIM
Intestinal Research 2021;19(2):239-246
Background/Aims:
Several studies have shown that colorectal neoplasms (CRN) including colorectal cancer (CRC) may be prevalent in patients with gastric cancer. However, in most of these studies, colonoscopy to investigate the prevalence of CRN was performed prior to surgery. We aimed to investigate whether CRN was more prevalent in postgastrectomy gastric cancer patients than in healthy individuals.
Methods:
We reviewed the medical records of those patients within a cohort of gastric cancer patients with gastrectomy who underwent colonoscopy between 2016 and 2017. Controls age- and sex-matched with gastric cancer patients at a 2:1 ratio were identified among those who underwent colonoscopy at a health-promotion center. The frequencies of CRN, advanced CRN (ACRN), and CRC among patients with gastrectomy were compared with those in the control subjects. A total of 744 individuals (gastric cancer, 248; control, 496) were included.
Results:
The rates of CRN and ACRN in the gastric cancer group were higher than those in the healthy individuals (CRN, 47.6% vs. 34.7%, P< 0.001; ACRN, 16.9% vs. 10.9%, P= 0.020). The rate of CRC was comparable between the 2 groups (2.0% vs. 0.6%, P= 0.125). Multivariate analysis identified previous gastrectomy for gastric cancer and male sex as significant risk factors for (A)CRN.
Conclusions
CRN and ACRN were more prevalent in patients who underwent surgery for gastric cancer than in the control group. Regular surveillance colonoscopy at appropriate intervals is indicated after gastrectomy.
9.A Case of Systemic Lupus Erythematosus and Abdominal Aorta Thrombosis Associated with Protein C and S Deficiency.
Jun Ho SONG ; Tae Geun GWEON ; Jun Ki MIN
The Journal of the Korean Rheumatism Association 2009;16(4):306-311
Thrombosis is a well known manifestation in patients with systemic lupus erythematosus, along with lupus anticoagulant, anticardiolipin antibody and anti beta2-glycoprotein I. We describe here a 44-year-old female with an abdominal aorta thrombosis of SLE and the patient had no antiphospholipid antibodies. She had this unusual site of thrombosis and this was associated with protein C and S deficiency. She had no other cause of thrombosis. After anticoagulant treatment, her thrombosis of the abdominal aorta resolved.
Adult
;
Antibodies, Anticardiolipin
;
Antibodies, Antiphospholipid
;
Aorta
;
Aorta, Abdominal
;
beta 2-Glycoprotein I
;
Female
;
Humans
;
Lupus Coagulation Inhibitor
;
Lupus Erythematosus, Systemic
;
Protein C
;
Thrombosis
10.An Economic Modeling Study of Helicobacter pylori Eradication: Comparison of Dual Priming Oligonucleotide-Based Multiplex Polymerase Chain Reaction and Empirical Treatment.
Tae Geun GWEON ; Joon Sung KIM ; Byung Wook KIM
Gut and Liver 2018;12(6):648-654
BACKGROUND/AIMS: Dual priming oligonucleotide-based multiplex polymerase chain reaction (DPO-based PCR) can detect the presence of clarithromycin resistance without culture. The aim of this study was to investigate the cost-effectiveness of DPO-based PCR for Helicobacter pylori eradication. METHODS: From 2015 to 2016, medical records of patients who received H. pylori eradication therapy were analyzed. Patients were divided into two groups: tailored group patients who were treated based on DPO-based PCR and empirical group patients. Eradication rate and medical cost, including diagnostic tests, eradication regimens, and 13C-urea breath tests, were compared between the two groups. Cost for one successful eradication was calculated in each group. The expected cost of eradication for empirical treatment was investigated by varying the treatment duration and eradication rate. RESULTS: A total of 527 patients were analyzed (tailored group 208, empirical group 319). The eradication success rate of the first-line therapy was higher in the tailored group compared to that in the empirical group (91.8% vs 72.1%, p < 0.01). The total medical cost for each group was 114.8±14.1 U.S. dollars (USD) and 85.8±24.4 USD, respectively (p < 0.01). The total medical costs for each ultimately successful eradication in the tailored group and in the empirical group were 120.0 USD and 92.4 USD, respectively. The economic modeling expected cost of a successful eradication after a 7- or 14-day empirical treatment was 93.8 to 111.4 USD and 126.3 to 149.9 USD, respectively. CONCLUSIONS: Based on economic modeling, the cost for a successful eradication using DPO-based PCR would be similar or superior to the expected cost of a successful eradication with a 14-day empirical treatment when the first-line eradication rate is 80%.
Breath Tests
;
Clarithromycin
;
Diagnostic Tests, Routine
;
Helicobacter pylori*
;
Helicobacter*
;
Humans
;
Medical Records
;
Models, Economic*
;
Multiplex Polymerase Chain Reaction*
;
Polymerase Chain Reaction