Christopher B. Williams

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BACKGROUND & AIMS Patients with ulcerative colitis are at increased risk of colorectal cancer. It is widely believed that this is secondary to colonic inflammation. However, the severity of colonic inflammation has never been shown to be a risk factor. METHODS We devised a case-control study of patients with long-standing extensive ulcerative colitis to(More)
BACKGROUND/AIMS Cancer surveillance in patients with ulcerative colitis is of unproven benefit. This study assesses the efficacy and analyzes factors limiting the success of a surveillance program during a 21-year period in 332 patients with ulcerative colitis to the hepatic flexure and disease duration exceeding 10 years. METHODS Clinical assessment and(More)
102 patients with familial adenomatous polyposis underwent upper gastrointestinal endoscopy as a screening test for gastroduodenal adenomas. 100 had duodenal abnormalities (dysplasia in 94, and hyperplasia in 6), usually in the second and third parts of the duodenum (91%). The periampullary area was abnormal in 87 of 97 patients who had a biopsy specimen(More)
BACKGROUND & AIMS The value of colonoscopic surveillance for neoplasia in long-standing extensive ulcerative colitis remains controversial. This study reports on prospectively collected data from a surveillance program over a 30-year period. METHODS Data were obtained from the prospective surveillance database, medical records, colonoscopy, and histology(More)
BACKGROUND/AIMS Cytokines are thought to be important in mediating tissue damage in inflammatory bowel disease (IBD). Many of the in vivo activities of tumor necrosis factor alpha (TNF-alpha) match the changes found in IBD, but its importance is controversial. METHODS A sensitive, reverse hemolytic plaque assay was used to determine the frequency of(More)
Clinical and pathological findings in 87 patients with juvenile polyposis have been reviewed; 1032 polyps were available from 80 of these patients; 840 were typical spherical juvenile polyps whereas 169 differed in being multilobulated or showing a villous configuration; 79 (46.7%) of the latter contained foci of epithelial dysplasia whereas only 76 (9.0%)(More)
The histopathological features and results of treatment of malignant polyps removed by endoscopic polypectomy from 60 patients are presented. The patients were followed for a minimum of five years. Forty six patients were treated by polypectomy alone as local excision was judged complete and the invasive carcinoma was well or moderately well differentiated.(More)
AIM To study the availability and quality of adult and paediatric colonoscopy in three National Health Service (NHS) regions. METHOD A prospective four month study of colonoscopies in North East Thames, West Midlands, and East Anglia. PATIENTS Subjects undergoing colonoscopy in 68 endoscopy units. RESULTS A total of 9223 colonoscopies were studied.(More)
The diagnostic and therapeutic benefits of colonoscopy are well known but most large-scale surveys, especially those involving multiple centres, may underestimate the range and incidence of complications. The detailed records of 5000 colonoscopies in a specialist unit have been analysed and conclusions drawn which may help to make the procedure safer. The(More)
BACKGROUND In our experience colonoscopy in women is more difficult than in men. A retrospective review of 2194 colonoscopies performed by a single experienced endoscopist (CBW) showed that 31% of examinations in women were considered technically difficult compared with 16% in men. METHODS To investigate a possible anatomic basis for this finding, normal(More)