Koichiro Sato

Favorable long-term clinical outcome of uncovered D-weave stent placement as definitive palliative treatment for malignant colorectal obstruction.

BACKGROUND: Most self-expandable metallic stents for colorectal placement are uncovered because of the high migration rate of covered stents. However, the optimal stent design for colorectal use remains unclear. OBJECTIVE: The purpose of this study was to evaluate the efficacy and safety of a double-wire woven uncovered stent for definitive palliative treatment of malignant colorectal obstruction. DESIGN: This study was a prospective, single-arm, observational clinical study of patients enrolled between December 2005 and September 2010. SETTINGS: This study was conducted at a referral hospital in Japan. PATIENTS: Twenty-four consecutive patients with malignant colorectal obstruction were included in the study. INTERVENTIONS: A double-wire woven uncovered stent was placed by use of a standard through-the-scope endoscopic placement technique. MAIN OUTCOME MEASURES: Technical, initial clinical, and long-term clinical success were measured. Long-term clinical success was defined as sustained relief of obstructive symptoms without reintervention until the patient’s death. RESULTS: The Karnofsky performance status score before stent placement was 60 (median, interquartile range, 42.5–67.5). Twenty of 24 patients had primary colorectal cancer, and 4 had extracolorectal malignancies. The site of obstruction was the ascending colon in 10 patients, descending colon in 4 patients, sigmoid colon in 7 patients, and rectum in 3 patients. Technical, initial, and long-term clinical success rates were 100%, 100%, and 83%. Median stent patency time was 149 days (interquartile range, 45–198 days). Median survival time after stent placement was 155 days (interquartile range, 68–231 days). Four patients (17%) had negative outcomes including stent occlusion by tumor ingrowth (8%) and stent migration (8%). The highest Karnofsky performance status score after stent placement was 70 (median; interquartile range, 50–70). The Karnofsky performance status score improved after stent placement (p = 0.002). LIMITATIONS: This study was limited because it was a single-arm, single-center study, and it had a small sample size. CONCLUSIONS: Endoscopic placement of double-wire woven uncovered stents is effective and safe as definitive palliative treatment for patients with malignant colorectal obstruction.

Factors associated with delayed gastric emptying in patients with stent placement for malignant gastric outlet obstruction

Background and study aims: Delayed gastric emptying (DGE) is an important factor in determining the clinical outcome in patients with stent placement for malignant gastric outlet obstruction but the factors associated with DGE remain unclear. The aim of this study was to investigate whether clinicopathologic data could be used to identify the factors for DGE in such patients. Patients and methods: A prospective, single-arm, observational clinical study was performed in a referral hospital in Japan. A total of 54 patients with stent placement for malignant gastric outlet obstruction were enrolled. A gastric emptying scintigraphy test was performed 1 week after stent placement. The relationship between DGE and clinicopathologic factors was investigated, and also the relationship between DGE and stent patency time, eating period (when the patient was able to maintain oral intake), and survival time. Results: A total of 38.9 % (21 /54) of patients had DGE. The following were identified as independent predictive factors of DGE: opioid use (odds ratio, 5.32; 95 % confidence interval [95 %CI], 1.07 – 26.41; p = 0.04), chemotherapy before stent placement (odds ratio, 8.03; 95 %CI, 1.85 – 34.95; p = 0.006), and smaller stent diameter (odds ratio, 13.59; 95 %CI, 1.72 – 107.41; p = 0.01). No relationship was found between DGE and the level of oral intake, stent patency time, eating period, and survival time. Conclusions: The factors associated with DGE after stent placement include those associated with the patient’s tumor as well as factors relating to their treatment, including stenting. The clinical and functional results after stent placement appear to be unrelated to the gastric emptying findings.

EVALUATION OF THE LOOPING FORMATION AND PAIN DURING INSERTION INTO THE CECUM IN COLONOSCOPY

Introduction:  One of the causes of pain during insertion of the colonoscope is stretching of the mesenterium by loop formation. The degree of pain differs according to the type of loop formation. Our aims were to study the accuracy of the colonoscopist’s assessment of the presence and type of loop formation and to study the degree of pain in relation to the type of loop by administering the visual analog scale (VAS).

A Case of a Child with an APC Pathogenic Mutation, Aberrant Expression of Splice Variants and Positive Family History of FAP

Familial adenomatous polyposis is an autosomal dominant hereditary disease characterized by the appearance of hundreds to thousands of colorectal adenomatous polyps; if left untreated, there is nearly a 100% lifetime risk of colorectal cancer. In the present case, adenomatous polyps were observed at 6 years of age. Unlike our previous assumption, adenomatous polyps were detected by colonoscopy at <10 years of age. Considering the clinical importance of early diagnosis, we report this case involving germline adenomatous polyposis coli mutation (c.1958G > C, GenBank: M74088.1) that caused an increase in the isoform without exon 15. Although this isoform has been reported previously, it remains controversial whether the variant is pathogenic or not because it was observed both in patients with familial adenomatous polyposis and in normal controls. Nonetheless, due to quantitative distortion of splice variants in adenomatous polyposis coli transcripts and the early development of adenomatous polyps, we believe that this variant may be pathogenic.