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Pathology of colorectal adenomas: a colonoscopic survey.

The size, histological type, and grade of dysplasia of a large series of colorectal adenomas removed by colonoscopic polypectomy were matched against other variables such as anatomical site, age, sex, and number of adenomas per patients. Special emphasis was placed on the criteria for grading dysplasia in adenomas and the possible significance of severe dysplasia as a selective marker for increased colorectal cancer risk. The results showed that small adenomas (mostly with mild dysplasia) were evenly distributed throughout the colorectum but that adenomas showing severe dysplasia (mostly the larger tumours, greater than 10 mm diameter) were concentrated in the left colon and rectum, particularly the sigmoid part which is also the segment with the highest risk of colorectal carcinoma in high risk populations. Severe dysplasia in adenomas appears to be a selective histopathological marker for increased colorectal cancer risk. It is closely linked with increasing age and numbers of adenomas per patient, with the large adenomas and particularly those with a villous component in their histology. Severe dysplasia and multiple adenomas could be valuable markers for selecting from the total adenoma population those most deserving of close surveillance in follow-up cancer prevention programmes. Conceptually it would appear advantageous to think in term of the dysplasia-carcinoma sequence in the colorectum rather than the polyp-cancer or adenoma-carcinoma sequence. The implications of these results in the study of the aetiology of colorectal cancer are discussed.

Adenoma↗

Motion - colonoscopic surveillance is more cost effective than colectomy in patients with ulcerative colitis: arguments against the motion.

There are insufficient data upon which to base recommendations about surveillance colonoscopy and prophylactic colectomy for the prevention of colorectal cancer in patients with ulcerative colitis. Case series, analyses of intermediate results and extrapolations from other patient groups do not constitute reliable evidence. Available studies are susceptible to several biases: the 'healthy worker' effect, surveillance bias and selection bias. Patients who are enrolled in surveillance programs are more likely to be thoroughly evaluated beforehand, are more likely to be given a diagnosis of dysplasia or neoplasm even when asymptomatic and are more likely to comply with medical treatment, including maintenance anti-inflammatory medication. Comparisons of the rates of neoplasia or death between surveyed and nonsurveyed patients are, therefore, of questionable validity. Prophylactic colectomy, unlike surveillance colonoscopy, prevents death from colorectal cancer. Moreover, it is difficult to keep patients in surveillance programs, and those who withdraw from programs appear to be at high risk of developing cancer. Prophylactic colectomy should be strongly considered for patients with dysplasia, sclerosing cholangitis, longstanding pancolitis (especially if it began early in life) or a positive family history of colorectal cancer. This procedure is underused in clinical practice and is a good alternative to colonoscopic surveillance in high risk patients.

Colectomy↗

Motion - colonoscopic surveillance is more cost effective than colectomy in patients with ulcerative colitis: Arguments for the motion.

Patients with ulcerative colitis (UC) are at increased risk for colorectal cancer (CRC), especially those with longstanding disease, pancolitis or primary sclerosing cholangitis. The incidence of colitis- associated cancer is increasing, and the mortality rates from CRC are higher in UC patients than in the general population. Case control studies have demonstrated that surveillance colonoscopy reduces the risk of dying from CRC. A well conducted decision analysis found that surveillance colonoscopy decreases cancer-related mortality and increases life expectancy. The results with surveillance programs were almost as good as with prophylactic colectomy. A subsequent cost effectiveness analysis using the same model found that, compared with a policy of no surveillance, colonoscopic surveillance was more effective at preventing death from CRC and was less costly. The best strategy appears to be to perform colonoscopies every three years. The analysis also showed that colectomy should be recommended in patients with low-grade dysplasia. Patients at very high risk for CRC should undergo yearly colonoscopy, and patients who are concerned about the limitations of this technique should be offered prophylactic colectomy.

Colectomy↗

Is colonoscopic screening of a low-risk (normal) population ethically justifiable?

This report summarizes the arguments for and against colonoscopic screening of a low-risk population for colorectal cancer. The strongest argument in favor of colonoscopy is that colonoscopy rarely misses an existing colorectal neoplasia and its precursor lesions and that procedural side effects are rare. In contrast, the combination of fecal occult blood test plus sigmoidoscopy leaves 10-15% of advanced neoplasms in the proximal colon undetected. However, colonoscopy is costly and the health care systems of only few European countries refund the respective costs. In addition, there is presently not sufficient manpower available to deliver colonoscopy to the public starting at the age of 50 in a 1:10 yearly frequency. Compliance to the procedure is very low even in countries which refund screening costs. Therefore, promotion of colonoscopy as the presently most effective screening procedure depends mainly on major educational efforts within the public to increase compliance as well as on the readiness of European health care systems to cover the respective costs.

Colonoscopy↗

Clinical significance of the colonoscopic allergen provocation test.

BACKGROUND: To improve the diagnosis of intestinal allergy, we developed a colonoscopic allergen provocation (COLAP) test. METHODS: The cecal mucosa was challenged with three food antigen extracts, a buffer control and a positive control (histamine). The mucosal wheal and flare reaction was registered semiquantitatively 20 min after challenge, and selected tissue biopsies were examined for mast cell and eosinophil activation by immunohistochemistry and electron microscopy. The COLAP test was performed on 70 adult patients with abdominal symptoms suspected to be related to food allergy and in 5 healthy volunteers. In parallel, skin prick tests were performed and IgE was measured in serum. RESULTS: 97 out of 210 antigen challenges performed in the patient group induced a significant wheal and flare reaction of the mucosa (46%), whereas no reaction in response to antigen was observed in healthy volunteers. Antigen-induced wheal and flare reactions were dependent on patients' histories of adverse reactions to food, but not on serum levels of specific IgE or skin test results. Degranulation of mast cells was observed in almost all tissues in which food antigens caused a wheal and flare reaction. Eosinophil activation was also highly correlated with the extent of the wheal and flare reaction (r(s) = 0.86). CONCLUSIONS: The data suggest that the COLAP test may be a useful diagnostic means in patients with suspected intestinal food allergy and a new tool for the study of underlying mechanisms.

Adult↗

Colonoscopic screening for colorectal cancer improves quality of life measures: a population-based screening study.

BACKGROUND: Screening asymptomatic individuals for neoplasia can have adverse consequences on quality of life. Colon cancer screening is widespread but the quality of life (QOL) consequences are unknown. This study determined the impact of screening colonoscopy on QOL measures in asymptomatic average-risk participants. METHODS: Asymptomatic male and female participants aged 55-74 years were randomly selected from the Australian Electoral Roll or six primary care physicians' databases. Participants completed the Short-Form (SF-36) Quality of Life Assessment at baseline and at a mean of 39 days after colonoscopy. Outcome measures were (i) significant changes in raw scores in any of the eight SF-36 domains assessed following colonoscopic screening and (ii) improvements or declines in previously validated categories, representing clinically significant changes, within any of the eight SF-36 domains. RESULTS: Baseline QOL measures were similar to those of a matched general population sample. Role Limitations due to Emotions, Mental Health and Vitality raw scores significantly improved following colonoscopy (P < 0.05, 2-tailed t-test). Health ratings according to Category were similar (same clinical status) in the majority of participants. However, 30% participants recorded clinically significant improvement in the Mental Health and Vitality domains (P < 0.05, Wilcoxon Signed-Ranks test). This improvement was not offset by declines in other domains or in other participants. Improvement in QOL was not related to colonoscopy results. CONCLUSION: Average-risk persons benefit significantly from colon cancer screening with colonoscopy, improving in Mental Health and Vitality domains of Quality of Life. This improvement is not offset by declines in other domains.

Adenomatous Polyps↗

The prevalence of colonic polyps in acromegaly: a colonoscopic and pathological study in 103 patients.

Patients with acromegaly are reported to be at risk of developing adenomatous colonic polyps, which are considered to be preneoplastic lesions. This assumption is, however, usually drawn from results obtained in rather small series of patients or without a control group. We, therefore, undertook a prospective colonoscopic and pathological study comprising 103 acromegalic patients and 138 nonacromegalic control subjects referred for irritable bowel syndrome. The prevalence of adenomatous colonic polyps was significantly increased in acromegalic patients compared to that in control subjects (22.3% vs. 8.0%; P = 0.0024). The significance was similarly present in male acromegalic patients (28.6% vs. 5.5% in male control subjects; P = 0.0026), but was absent in female acromegalic patients. The prevalence of colonic polyps was also significantly increased in the group of acromegalic patients under 55 yr of age (20.0% vs. 3.0% in the control group of the same age; P = 0.0026). Other characteristics of adenomatous colonic polyps in acromegaly were the multiplicity and the presence proximal to the splenic flexure. No difference in the duration of acromegaly was found between patients with or without adenomatous polyps. The prevalence of hyperplastic colonic polyps was also significantly increased to 24.3% in acromegalic patients vs 4.4% in control subjects (P < 0.001). In conclusion, in view of the increased incidence of adenomatous colonic polyps, colonoscopy should be part of the follow-up examination in acromegaly.

Acromegaly↗

Colonoscopic polypectomy with local injection of methylene blue.

For safer and complete colonoscopic polypectomy of large broad-based adenomas, we attempted submucosal injection of methylene blue before electrosurgical snare excision. Twenty-five large broad-based sessile adenomas 20 mm or more in diameter were resected. Methylene blue was injected about 2 mm away from the edge of the lesion. After injection, the lesion appearing as a blue bleb was resected by snare polypectomy. All the lesions were completely resected by single-step polypectomy. During and after polypectomy, no complication occurred. Endoscopic resection of large sessile adenomas with the aid of submucosal injection of methylene blue thus appears to be safe and effective.

Adenomatous Polyps↗

Complications associated with 355 flexible colonoscopic procedures in dogs.

Flexible colonoscopy is commonly performed in dogs with signs of large-bowel diseases. Although considered to be a safe procedure, no reports of complications associated with colonoscopy have appeared in the veterinary literature. The purpose of this study was to describe the frequency and types of adverse events that developed during flexible colonoscopy in dogs. Medical records were reviewed from 355 scheduled colonoscopic procedures. Major complications were defined as adverse events in which the dog's life was potentially jeopardized and the complication required intensive treatment or monitoring. Major complications consisting of fatal aspiration of GoLYTELY, colonic perforation, and excessive hemorrhage after biopsy of an adenocarcinoma with rigid forceps occurred in 3 (0.85%) dogs. Minor complications associated with anesthesia or colonoscopy occurred during 3.4% of procedures. Complications were classified as minor if the adverse event required minimal treatment or monitoring, and the complication was not considered a threat to the dog's life. Vomiting of GoLYTELY occurred with the administration of 4.6% of doses in 6.5% of dogs. When administering GoLYTELY, clinicians should be prepared to rapidly remove the orogastric tube and mouth speculum if vomiting occurs to reduce the potential for aspiration. In this group of dogs undergoing flexible colonoscopy, major complications occurred infrequently and minor complications developed uncommonly. Overall, minor or major complications developed during 30 (8.5%) of 355 procedures. Mortality was rare (0.28%). Flexible colonoscopy appears to be a safe procedure in dogs with signs of large-bowel diseases.

Animals↗

Drug targets in colonoscopic polypectomy: biological sealants with special reference to fibrin-glue (tissucol).

The increasing outpatient use of colonoscopy in the diagnostic study and prophylaxis of colon diseases has allowed early identification of polypoid neoformations, thus indicating their increased incidence during the asymptomatic phase. In this respect, the application of biological sealants immediately before the polypectomy has represented a novel therapeutic strategy in the treatment of these preneoplastic lesions. The injection of biological sealants with needle under the polyp peduncle or sub-mucosa has demonstrated a protective action on the electrocoagulated area, an anti-haemorrhagic effect owing to the strengthened seal of the eschar that is formed, and a facilitated tissue regeneration, respectively. The author report his experience acquired over the past five years with regard to the use of biological sealant in colonoscopic polypectomy and conclude that biological sealants, a human fibrin glue, which utilises components of the human plasma, may allow a more generous removal of neoformations, the absence of post-polypectomy complications and, consequently, the dramatic reduction of time of patient's admission in the hospital. In fact, all patients were discharged after two hours from polypectomy, thus implying a better quality of life for patients, in the absence of post-operative complications and a reduction of non-medical costs.

Colonic Polyps↗

Colonoscopic biopsies and cytological examination in chronic ulcerative colitis.

Both multiple colonoscopic biopsies and brushing specimens for detection of any premalignant epithelial lesion were taken in 50 patients with long-standing ulcerative colitis. In 25 of the cases centrifuge sediment of enema return before the endoscopy was examined cytologically. The three methods were compared with respect to yield of colonic epithelium and occurrence of epithelial atypia. Enema return contained only a little glandular epithelium, which showed no atypical changes. Both biopsy and brushing yielded an abundance of epithelium. Biopsies showed a considerably higher frequency of epithelial atypia, especially of mild degree, and in two cases precancerous lesions were demonstrated only in the biopsies. In seven cases, on the other hand, moderate or severe atypia was found in brushing specimens when biopsies only revealed mild reactive changes.

Adolescent↗

Distribution of polyps in the large bowel in relation to age. A colonoscopic study.

In a colonoscopic study of the anatomical distribution of 600 adenomas, polyps of all sizes in patients up to 55 years old were predominantly located distally. With advancing age of the patients a successively greater proportion of at first small and then also larger polyps was found in the intermediate and proximal parts of the colon. These findings support the assumption that polyps of the gut as a rule originate in the distal part of the large bowel, only later to appear proximally. This concept is important, since it might serve to explain conflicting experience with regard to the site of colorectal tumours.

Age Factors↗

Colonoscopic screening examination of relatives of patients with colorectal cancer. I. A comparison with an endoscopically screened normal population.

First-degree relatives (n = 206) of patients operated on for colorectal cancer (CRC) (n = 181) were offered a colonoscopic screening examination; 169 relatives (82%) attended. The findings were compared with those in a normal population sample with no CRC in first-degree relatives (n = 308), aged 50-59 years, who had been screened by means of flexible sigmoidoscopy. Three carcinomas and 176 polyps were found in 56 of 95 male relatives (57%) and 34 of 74 female relatives (46%). The adenoma prevalence rate was 37 (39%) and 26 (35%) for male and female relatives, respectively. In the 50- to 59-year age group, the adenoma prevalence rates for both sexes collectively and for women separately were significantly higher among relatives than among the population without CRC relatives. Hyperplastic polyps were larger, whereas adenomas were similar in size among relatives compared with the normal population. Colonoscopy may be a suitable method of choice for screening first-degree relatives of patients with CRC.

Adenoma↗

Potential of measurements of unsaturated vitamin B12-binding capacity in serial colonoscopic biopsy specimens for global and regional assessments of disease severity in inflammatory bowel disease.

We investigated whether measurements of unsaturated vitamin B12-binding capacity (UBBC), in homogenates of serial colonoscopic biopsy specimens, could be used as objective measures of disease severity in ulcerative colitis (UC) and Crohn's disease (CD). On a regional basis UBBC activity correlated with and showed good agreement with endoscopic and histologic activity scores (r = 0.8 and 0.6, respectively, for UC, and r = 0.7 and 0.7, respectively, for CD). For global assessment aggregate UBBC, endoscopic and histologic scores were compared with standard clinical activity scores. In UC, correlations with the van Hees index were r = 0.7, 0.8, and 0.7, respectively, and UBBC assays accurately reflected both regional and global disease activity. In CD, correlations with the CDAI were -0.1, 0.7, and 0.6, respectively. Thus, aggregate UBBC scores failed to reflect disease activity in CD, in which focal deep ulcers may produce high symptom scores but in which adjacent specimens may show no acute inflammation.

Biomarkers↗

Laboratory markers of colonoscopic activity in ulcerative colitis and Crohn's colitis.

BACKGROUND: Previous studies have not identified a convenient laboratory marker of colonoscopic activity in Crohn's colitis or ulcerative colitis. METHODS: Twenty-eight patients with either ulcerative colitis or Crohn's colitis undergoing colonoscopy by the same observed had laboratory measurements of serum albumin, orosomucoid, C-reactive protein, plasma viscosity, haemoglobin, leucocyte and platelet counts, and faecal alpha-1-antitrypsin from single non-lyophilized samples. Multiple linear regression was performed using each laboratory variable as the dependent variable and the lengths of each grade of endoscopic activity as the explanatory variables. RESULTS: Multiple regression analysis using all the endoscopic grades of acute activity showed significant correlations with faecal alpha-1-antitrypsin (p < 0.001), serum albumin (p < 0.001), C-reactive protein (p = 0.02), and plasma viscosity (p = 0.03). CONCLUSIONS: The highest multiple correlation coefficients were obtained with faecal alpha-1-antitrypsin (r = 0.82) and serum albumin (r = 0.80), and these measurements can be recommended as convenient markers of endoscopic activity in these diseases.

Adult↗

Twenty years' colonoscopic surveillance of patients with ulcerative colitis. Detection of dysplastic and malignant transformation.

BACKGROUND: Endoscopic cancer surveillance in patients with ulcerative colitis has been performed for almost 3 decades. There is still no consensus on its clinical value. METHODS: This study evaluates a 20-year prospective study of 143 patients with extensive ulcerative colitis and a disease duration exceeding 10 years. Colonoscopy with double biopsy specimens from nine locations of the colon was performed every 2nd year. Biopsy specimens showing dysplasia were reviewed at the end of the study. RESULTS: Through the surveillance dysplasia/cancer was detected in 55 patients; 7 of these patients had carcinomas, and 2 were in a possibly curable stage (Dukes A). The predictive value of low-grade dysplasia for either high-grade dysplasia or cancer was 41%. CONCLUSIONS: Although impaired by limiting factors, colonoscopic surveillance of chronic extensive colitis may identify patients with dysplasia and thereby prevent malignant transformation.

Adult↗

[Comparison of complications in colonoscopic treatment in elderly and young subjects].

PURPOSE: Owing to a recent increase in incidence of colonic adenoma and adenocarcinoma, colonoscopic treatments for elderly subjects are performed more frequently. We analyzed differences in complications between elderly and young subjects. OBJECT AND PROCEDURE: Subjects that had been treated with colonoscopy at Keio Cancer Center, were divided into two groups: one group (436) consisting of subjects below the age of 65, the other (176) consisting of subjects 65 and over. We analyzed differences in symptoms, complications and pathological findings. RESULT: No significant statistical differences were found in the occurrence of adenoma and adenocarcinoma between the young and the elderly group. COMPLICATIONS: Pain occurred in 9.4% of the young group and 10.2% of the elderly group, showing no significant difference between the two groups. Bleeding occurred in 0.7% of the young group and 3.8% of the elderly group and ulcerative scars were found in two of the latter. CONCLUSION: In the elderly the regenerative capacity of damaged blood vessels and tissues is greatly reduced, therefore bleeding and ulceration occurred more frequently. It was thus concluded that it is very important for elderly group to rest after endoscopical mucosal resection, polypectomy and biopsy in order to minimize the risk of bleeding in the digestive tract.

Adenocarcinoma↗

Colonoscopic diagnosis of appendiceal intussusception: a case report.

Intussusception of the appendix is an uncommon condition and the diagnosis is rarely made preoperatively. Intussusception of the appendix may mimic a neoplastic lesion. Colonoscopy is a valuable tool for diagnosis of the appendiceal intussusception. A 17-yr-old female admitted with repeated abdominal pain, nausea, vomiting and febrile sensation. We diagnosed as appendiceal intussusception by colonoscopy, which showed a polypoid tumor (about 1.5 cm) in the cecum. This sessile polypoid mass looks like foreskin or glans. We present colonoscopic finding of appendiceal intussusception and review the literature.

Adolescent↗