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.

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.

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.

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.

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.

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.

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

A Clostridioides difficile infection (CDI) is one of the major nosocomial diarrheal diseases. Pseudomembranous colitis (PMC) is a characteristic endoscopic finding of CDI, manifested by white or yellowish plaque covering the colonic mucosa. Ischemic colitis is inflammation of the colon manifested by mucosal denudation and friability. Ischemic colitis is rarely associated with CDI. The treatment response might be delayed when CDI is complicated with other diseases that cause diarrhea. Thus far, reports of CDI concomitant with Cytomegalovirus (CMV) colitis are rare. This paper reports a case of PMC and ischemic colitis associated with CDI and CMV infection. After two weeks of oral vancomycin and intravenous metronidazole, the patient’s diarrhea was not improved. Follow-up sigmoidoscopy was performed, and a CMV infection was identified at areas of broad ulceration where ischemic colitis occurred.Finally, the patient was cured with ganciclovir. Follow-up sigmoidoscopy showed an improvement in ischemic colitis.