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Biomedical subjects

B C Morson

Publications and source records attributed to B C Morson.

At least 55 records · Page 3Linked to original sources
PubMed1983

Macroscopic lesions in dysplasia and carcinoma complicating ulcerative colitis.

Visible changes associated with dysplasia or carcinoma have been assessed in 62 colectomy specimens from patients with ulcerative colitis. In 34 colectomy specimens with one or more carcinomas, there were 51 visible carcinomas and 65 macroscopic dysplastic lesions; only one carcinoma was found in flat mucosa. Among 28 specimens with microscopic dysplasia but no carcinoma, eight contained no visible dysplastic lesion, and the remaining 20 contained a total of 40 polypoid or elevated dysplastic areas. In 32 operative specimens removed for long-standing chronic colitis without dysplasia or carcinoma, nine contained visible inflammatory polypoid lesions. On radiological or endoscopic examination of the colon in long-standing colitis close attention should be given to the identification and biopsy of polyps, elevated nodular areas or plaques, strictures, and isolated ulcers. It is likely that colectomy specimens with visible polypoid or elevated dysplastic lesions will contain a carcinoma more often than those removed for dysplasia in flat mucosa.

Carcinoma↗
PubMed1983

Dysplasia in inflammatory bowel disease: standardized classification with provisional clinical applications.

Assessment of epithelial dysplasia in ulcerative colitis has been hindered by inconsistencies in and disagreements about nomenclature and interpretation. To resolve these issues, pathologists from ten institutions participated in three exchanges of multiple slides and, following each exchange, in discussions of the results. A classification system for the epithelial changes that occur in ulcerative colitis was developed, which should be applicable to other forms of inflammatory bowel disease as well. The classification makes use of standardized terminology, addresses specific problem areas, and offers practical solutions. The reproducibility of the system was studied by means of examinations of both inter- and intra-observer variations. The clinical implications of the findings were incorporated into suggestions for patient management. The basis of the classification is that the term "dysplasia" is reserved for epithelial changes that are unequivocally neoplastic and may therefore give rise directly to invasive carcinoma. Specimens are categorized as negative, indefinite, or positive for dysplasia. The negative category includes all inflammatory and regenerative lesions and indicates that only continued regular surveillance is required. The indefinite category is applied to epithelial changes that appear to exceed the limits of ordinary regeneration but are insufficient for an unequivocal diagnosis of dysplasia or are associated with other features that prevent such unequivocal diagnosis. Clinically, it indicates that early repeat biopsy is often required to assess the changes more accurately. The positive category is divided into two subcategories: 1) high-grade dysplasia, for which colectomy should be strongly considered after confirmation of the diagnosis, and 2) low-grade dysplasia, which also requires confirmation and early repeat biopsy or colectomy, depending on other findings.

Biopsy↗
PubMed1982

A randomized trial of ascorbic acid in polyposis coli.

The possibility of pharmacological control of large bowel adenomas has been suggested by effectiveness of antioxidants in experimental tumor models and by the results of a limited clinical study using ascorbic acid. Over a two year period we tested this hypothesis in a randomized, double-blind study of 49 patients with polyposis coli. Of 36 patients who were evaluable at completion, 19 had received ascorbic acid, 3 g/day, and 17 had received a placebo. We found a reduction in polyp area in the ascorbic acid-treated group at nine months of follow-up (P less than 0.03) and trends toward reduction in both number and area of rectal polyps during the middle of the trial. A labeling study of rectal epithelium with tritiated thymidine also hinted at a treatment effect. Our data suggest that ascorbic acid temporarily influenced polyp growth or turnover. Although these results have no current therapeutic value, our findings support continued studies of chemoprevention in this and other high risk settings.

Adult↗
PubMed1982

Colonoscopic diagnosis of minimal change colitis in patients with a normal sigmoidoscopy and normal air-contrast barium enema.

8 patients with normal sigmoidoscopic appearances and normal results by high-quality air contrast barium enema had substantial or total colitis diagnosed for the first time at colonoscopy performed within a month of the radiological examination. Colitis was confirmed in all 8 patients by histological examination of biopsy specimens. Barium enema radiographs were independently reviewed by three experienced observers who also reviewed other normal and abnormal radiographs. One observer regarded all 8 sets of radiographs from the patients with colitis as being of normal appearance, and 4 patients were reported as having normal radiographs by all three observers. All 7 of the rectal biopsy specimens taken showed histological features of inflammatory bowel disease. This emphasises the importance of performing a rectal biopsy in patients with gastrointestinal symptoms of unknown cause.

Adult↗
PubMed1982

En face histopathologic technic for examining colonic mucosa of resection specimens.

The en face histopathologic technic for examining colonic mucosa in the plane of the luminal surface is described and analyzed. Grossly normal colonic mucosa from 56 resection specimens was embedded en face and sectioned. The en face histopathologic slides showed sheets of mucosa with the crypts in cross section surrounded by lamina propria, an orientation to mucosal topography analogous to gross examination. A total of 1,931 cm2 of mucosa was embedded en face in 640 paraffin blocks, a mean of 3.0 +/- 0.8 (SD) cm2 per block. With routine processing of the same surface area, approximately 2,365 blocks (nearly four times as many as for the en face technic) would have been required. A total of 1,217 cm2 of mucosa appeared in the slides from the en face blocks, comprising 63 +/- 23% of the submitted tissue, compared with 0.3% in routine sections. Our analysis demonstrated that the en face technic is a useful tool in histopathologic studies of large areas of grossly normal colonic mucosa, particularly for quantitation and mapping of the findings.

Colon↗
PubMed1982

Medical audit of rectal biopsy diagnosis of inflammatory bowel disease.

The records of the rectal biopsy diagnoses of ulcerative colitis and Crohn's disease in the Department of Pathology, St Mark's Hospital, London, were reviewed. The biopsy diagnoses were compared to subsequent resection diagnoses on the same patients, and annual and seasonal variations in the frequency of these and related diagnoses were studied. The accuracy rate for the biopsy diagnosis of ulcerative colitis was about 70% and for Crohn's disease about 40% each time a biopsy was read. The low figure for the accuracy rate for Crohn's disease could be attributed to sampling error inherent in the diagnosis of a disease which is essentially patchy, showing discontinuous pathology. Also, many patients with Crohn's disease have a normal rectum which is biopsied to demonstrate the distinction from ulcerative colitis. In practical terms therefore a 40% accuracy rate in Crohn's disease is probably adequate. The rate of "false-positive" diagnoses was about 5%. There was a seasonal variation in the frequency of these two diagnoses, but no variation attributable to changes in observers, as pathology trainees in the Department change regularly. The frequency of diagnoses of non-specific inflammation and of normal colon did show such non-random variations.

Adenocarcinoma↗
PubMed1982

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↗
PubMed1982

A clinicopathological study of acute colitis: the dilemma of transient colitis syndrome.

In a 5-year clinicopathological study of acute colitis involving 238 adults, 42 patients were found to have 'transient colitis syndrome'. This is a term we have developed to describe those patients who have a short-duration self-limiting acute colitis of abrupt onset and negative bacteriology and which does not recur. Analysis of clinical features suggests an infective aetiology for most cases of transient colitis syndrome. The histology varied from changes of infective colitis to that of inflammatory bowel disease. It is likely that many patients who are now enjoying permanent remission after a single attack of 'inflammatory bowel disease' had this transient colitis syndrome.

Acute Disease↗
PubMed1981

Spread of rectal cancer within veins. Histologic features and clinical significance.

Histologic evidence of venous invasion was demonstrated in 52 percent of 703 cases of rectal carcinoma. Quantitation of venous invasion and follow-up study showed that invasion of extramural veins was associated with a low 5 year survival rate (33 percent), whereas invasion limited to intramural veins was not. Spread into thick-walled extramural veins carries a very poor prognosis (15 of 91 patients survived 5 years). The corrected 5 year survival rate for stage C patients with invasion of thick-walled extramural veins was only 8 percent. Host reactions in and around the walls of invaded veins increase the survival rate; inflammatory damage to the vein walls and endarteritis obliterans are particularly important in this respect.

Adenocarcinoma↗