Preoperative colonoscopy for detection of synchronous neoplasms after insertion of self-expandable metal stents in occlusive colorectal cancer: comparison of covered and uncovered stents.

BACKGROUND/AIMS: In patients with occlusive colorectal cancers, a complete preoperative evaluation of the colon proximal to the obstruction is often impossible. We aimed to evaluate the feasibility of preoperative colonoscopy after stent placement and to determine whether the success rate of colonoscopy differs between covered and uncovered stents. METHODS: Seventy-three patients with malignant colorectal obstruction were enrolled prospectively. In patients with a resectable cancer, a preoperative colonoscopy was performed after insertion of a self-expandable metal stent (SEMS). The success rate of complete preoperative colonoscopy was compared between covered and uncovered stents. RESULTS: Forty-five of 73 patients who underwent stent placement had a resectable cancer (61.6%). A complete preoperative colonoscopy was possible in 40 of 45 patients (88.9%). The success rate of complete preoperative colonoscopy was significantly lower in the covered-stent group when the obstructing mass lesion was located in the sigmoid colon (p=0.024). Synchronous cancer was detected in one patient (2.2%). Stent migration was observed in four patients with a covered stent. CONCLUSIONS: A preoperative complete colonoscopy after SEMS placement was feasible and safe in most patients with malignant colorectal obstruction. Uncovered stents seem to have more advantages than covered stents in preoperative colonoscopy proximal to the obstruction.

A large polypoid vascular ectasia removed by using a polypectomy with a detachable snare in an asymptomatic patient.

Vascular ectasia is a well-known cause of lower gastrointestinal bleeding in the elderly. Endoscopically, it usually appears as a flat or elevated bright red lesion. We report on an extremely rare case of a large, pedunculated, polypoid vascular ectasia in an asymptomatic patient. A large pedunculated polypoid mass in the sigmoid colon was observed on colonoscopy during a regular health check-up, and a polypectomy was performed using a detachable snare. In histology, vessels with massive dilation were found mainly in the submucosa, which was consistent with vascular ectasia.

How can we predict the presence of missed synchronous lesions after endoscopic submucosal dissection for early gastric cancers or gastric adenomas?

GOALS: To identify predictive factors associated with the presence of missed synchronous lesions after endoscopic submucosal dissection (ESD) for gastric adenoma or early gastric cancer (EGC). BACKGROUND: Secondary gastric neoplasms that develop during follow-up period after ESD for gastric adenoma or EGC are divided into metachronous lesions and missed synchronous lesions. METHODS: ESD was performed in 250 patients with EGC or gastric adenoma. The patients with endoscopic follow-ups of <1 year, patients without curative resection, and patients with additional surgery were excluded from the study. Missed synchronous lesions were defined as secondary gastric neoplasms detected within one year of ESD but initially missed. We compared clinicopathologic factors between patients with missed synchronous lesions and patients without missed synchronous lesions. RESULTS: Missed synchronous lesions were found in 11.6% of the patients (29/250). The occurrence of missed synchronous lesions had significant correlation with tumor number at the time of ESD and age in the univariate analysis. Tumor number at the time of ESD and age were significant independent predictive factors for presence of missed synchronous lesions by multivariate logistic regression analysis (odds ratio 5.302, P = 0.006; odds ratio 2.315, P = 0.040, respectively). Missed synchronous lesions tended to be smaller, often located in the same third of the stomach as the main lesions. CONCLUSIONS: Tumor number at the time of ESD and age could be predictive factors for the presence of missed synchronous lesions after ESD. Careful endoscopic surveillance should be performed after ESD for multiple lesions or for elderly patients.

Insertion of self expandable metal stent for malignant stomal obstruction in a patient with advanced colon cancer.

Self expandable metal stent can be used both as palliative treatment for malignant colorectal obstruction and as a bridge to surgery in patients with potentially resectable colorectal cancer. Here, we report a case of successful relief of malignant stomal obstruction using a metal stent. A 56-year-old man underwent loop ileostomy and was given palliative chemotherapy for ascending colon cancer with peritoneal carcinomatosis. Eight months after the surgery, he complained of abdominal pain and decreased fecal output. Computed tomography and endoscopy revealed malignant stomal obstruction. Due to his poor clinical condition, we inserted the stent at the stomal orifice, instead of additional surgery, and his obstructive symptoms were successfully relieved. Stent insertion is thought to be a good alternative treatment for malignant stomal obstruction, instead of surgery.

Risk factors for perforations associated with endoscopic submucosal dissection in gastric lesions: emphasis on perforation type.

BACKGROUND: Endoscopic submucosal dissection (ESD) enables en bloc resection of larger gastric neoplasms. However, the procedure is associated with a high incidence of perforation. Perforations during ESD are divided into macro- and microperforations. Although both types of perforations could cause widespread tissue injury and secondary sepsis, very little is known concerning the risk factors for perforations according to the type of perforation. Thus, this study was performed to evaluate the risk factors for macro-, micro-, and all perforations (both) during ESD. METHODS: 823 gastric lesions (gastric adenoma or early gastric cancer) in 729 patients treated by ESD were enrolled, and their records were reviewed retrospectively. Risk factors were evaluated, focusing on age, sex, gastric neoplasm-related factors (12 locations, resected size, gross type of lesions, presence of ulceration, presence of fibrosis, pathologic diagnosis, and depth of invasion), and ESD procedure-related factors (type of knife, immediate bleeding during ESD, en bloc resection, procedure time, and the number of ESD cases experienced by the endoscopist). RESULTS: Of the 823 gastric lesions, the rates of all perforation, macroperforation, and microperforation were 9.6%, 7.5%, and 2.1%, respectively. Risk factors for all perforations on multivariate analysis were location of tumor in upper portion, presence of fibrosis, and long procedure time (>2 h). Risk factors for macroperforations were the same as all perforations. Risk factors for microperforations on multivariate analysis were old age (≥81 years), depth of invasion (muscularis mucosa), and long procedure time (>2 h). CONCLUSIONS: The risk factors for perforations during ESD could differ according to the type of perforation. Therefore, although macroperforation did not develop during ESD, it would be necessary to consider the possibility of microperforation in case of old age, long procedure time, and (deep) depth of invasion.

Inverse association of peripheral blood CD4(+) invariant natural killer T cells with atopy in human asthma.

Invariant natural killer T (iNKT) cells have been reported to play a role in the pathogenesis of murine asthma. However, the role for iNKT cells in the pathogenesis of human asthma is not defined. In this study we aimed to determined how blood iNKT cells are associated with atopy in asthmatic individuals. Peripheral blood mononuclear cells were isolated from 45 asthmatic subjects. iNKT cells were stained with 6B11 mAb, anti-TCRvalpha24 mAb, or alpha-galactosylceramide (GalCer)-loaded CD1d- tetramer and analyzed with flow-cytometric assays. Increased serum total IgE or one or more positive skin reactions to common allergens were used as atopic indexes. Asthmatic subjects with IgE > 500 IU/ml showed lower frequency of CD4(+) 6B11(+) iNKT cells (p < 0.01) or CD4(+) Valpha24(+) iNKT cells (p < 0.01) compared with subjects with IgE < or = 500 IU/ml. Asthmatic subjects with atopy on skin tests had lower frequency of CD4(+) alpha-GalCer-loaded CD1d- tetramer(+) iNKT cells compared with those without atopy (p < 0.05). The frequency of CD4(+) Valpha24(+) iNKT cells was negatively correlated with total IgE in asthmatic subjects (r = -0.33, p < 0.05). In summary, blood CD4(+) iNKT cells were inversely associated with atopic indexes in asthmatic individuals. We hypothesize that blood CD4(+) iNKT cells might behave like T(h)1-like iNKT cells in human asthma.

Late local urticaria as a long-term sequela of allergen-specific immunotherapy.

Local reaction to allergen-specific immunotherapy (SIT) usually appears within 30 minutes, but cases with exercise-induced urticaria at the SIT site 2-3 weeks after the last allergen injection have been reported. A 28-year-old man was treated with house dust mite-SIT for 5 years, due to asthma when he was an 11-year-old boy. On a treadmill exercise test for 50 minutes, erythema, swelling, and pruritus occurred at the SIT site, which lasted for one hour. There was no evidence of complement activation, and the skin biopsy specimens showed no apparent difference between the lesion and normal sites in the distribution of inflammatory cells and in mast cell degranulation. However, the morphine, but not the histamine, skin test responses were increased after the exercise. There must be a remaining long-term sequela of the SIT, including an increased releasability of mast cells, even after more than 10 years.