Findings Of Low-grade Dysplasia Research Articles

PTU-067 The Fate Of Flat Low-grade Dysplasia In Ulcerative Colitis

IntroductionThe natural history of low- grade dysplasia (LGD) found during colonoscopic surveillance of ulcerative colitis is not clear. The optimum strategy, either continued surveillance or immediate colectomy, is debated. The...

Endoscopic treatment of dysplasia in ulcerative colitis – medium term outcome

IntroductionUntil recently a finding of low grade dysplasia within a segment of colitis was an indication for colectomy. However, recent literature suggests that well-circumscribed lesions could be managed by endoscopic...

Altered expression of CK7 and CK20 in preneoplastic and neoplastic lesions in ulcerative colitis

This study is based on all patients with ulcerative colitis from a defined catchment area in Northern Sweden in a still ongoing colonoscopy surveillance programme, which started in 1977. From this material we selected tissue from eight groups of patients consisting of normal control biopsies (5), inactive colitis (10), active colitis (10), findings of low-grade dysplasia (10), high-grade dysplasia (6), aneuploidy (without dysplasia and with subsequent dysplasia) (10), and ulcerative colitis-associated cancers (5). The samples were evaluated according to immunohistochemical expression of CK7 and CK20. Colonic mucosa from normal controls and inactive colitis was found to be completely negative for CK7. In 9 out of 10 patients with active colitis, CK7 was sparsely expressed in a patchy manner and connected with active epithelial inflammatory areas. 7 out of 10 patients with low-grade dysplasia and 3 out of 6 with high-grade dysplasia were positive for CK7. Samples with aneuploidy without dysplasia were completely negative, while 2 out of 6 showing subsequent dysplasia were positive. Of the five cancers, two were positive for CK7. CK20 was expressed in nearly all samples but relatively more in the lower part of the crypts in neoplasia-associated lesions. Our results indicate a possible relationship between expression of CK7 and CK20 and neoplastic development of colorectal mucosa in patients with ulcerative colitis. Further studies are needed to elucidate whether these findings have clinical significance.

Screening Strategies in Gastrointestinal Cancer

The concept of screening is based on the notion that regular examination can reduce the mortality from gastrointestinal cancer, but there is as yet little evidence that this is the case in either Barrett's esophagus or ulcerative colitis. Screening is carried out by regular endoscopy with multiple biopsies in an attempt to detect dysplasia, which has traditionally been regarded as the end point of surveillance and the time when resection should be considered. Considerable departure from these guidelines has occurred. Attempts are increasingly being made to select patients in both of these groups who might be at particular high risk of developing dysplasia because of the presence of nuclear aneuploidy, the assumption being that these patients are at particular risk of developing dysplasia and carcinoma. However, data to support stratification at this level are unavailable. In addition, there is not good agreement as to whether surveillance is indicated at all in some groups of patients such as those with less than total colitis or short-segment Barrett's esophagus. The end point of surveillance has also been questioned, with reluctance to recommend colectomy in ulcerative colitis with the finding of low-grade dysplasia, possibly because the sampling problem is so great that it may be impossible to confirm that diagnosis on repeated endoscopy and biopsy. While better markers than dysplasia may be required to predict patients at highest risk, there are currently no marker other than the development of invasive carcinoma on which the decision to resect can be based.(ABSTRACT TRUNCATED AT 250 WORDS)