摘要:

&NA;Analysis of relative polyp locations in 426 consecutive patients with multiple colonic polyps found on colonoscopy showed novel findings. First, synchronous and metachronous neoplastic polyps showed spatial clustering in individual patients. For example, patients with their largest neoplasm in the cecum or proximal ascending colon, had 34.3 percent±4.6 percent (standard error) of their other colonic neoplasms in the same location. Second, hyperplastic polyps showed spatial clustering in individuals that was statistically significantly greater than expected from the increased hyperplastic polyp concentration in the rectum and sigmoid. Third, hyperplastic polyps showed spatial clustering with neoplastic polyps; this clustering was similar in magnitude to clustering for exclusively hyperplastic or neoplastic polyps. In contrast, lipomas were not spatially clustered with hyperplastic and neoplastic polyps. The magnitude of clustering between hyperplas and neoplasia showed a closer association between these histologic types than previously appreciated. Because of clustering, regions with prior polyps appear to merit closer surveillance. These findings suggest clinical study, using a randomized controlled clinical trial, of whether a patient who had only rectal and sigmoid adenomas on initial and follow‐up colonoscopy should have surveillance with flexible sigmoidoscopy alternating annually with colonoscopy. A patient with a prior cecal adenoma should have surveillance only with a complete colonoscopy or adequate cecal views on barium enema.

ISSN:0012-3706    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

&NA;To establish whether patients with indeterminant colitis (patients with ulcerative colitis whose surgical specimens also show features of Crohn's colitis) have an adverse outcome after ileal pouch‐anal anastomosis (IPAA), the authors reviewed the pathologic reports and postoperative status of 514 consecutive patients who underwent IPAA for chronic ulcerative colitis (CUC). Twenty‐five patients (5 percent) had features of indeterminant colitis (IC), including unusual distribution of inflammation, deep linear ulcers, neural proliferation, transmural inflammation, fissures, creeping fat, and retention of gobletcell population. The clinical and functional outcome of these 25 IC patients was compared with that of the remaining 489 CUC patients. The mean follow‐up was 38±18 months. No significant differences in complication rates, pouch function, incidence of “pouchitis,” or requirement for pouch excision were detected in the two groups at follow‐up. Although the authors are continuing to perform IPAA on patients with IC, a better definition of the IC patient and a more objective, prospective analysis of outcome of IC following IPAA is required before confident and specific treatment policies can be recommended.

ISSN:0012-3706    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

&NA;DNA extracted from 31 primary colorectal carcinomas was analyzed for the presence ofrasgene amplification and mutations. Nine carcinomas had Ha‐rasamplification and seven Ki‐rasamplification. Nine carcinomas had codon 12 Ki‐rasmutations. Immunohistochemical staining forrasproteins revealed a normal membrane association in normal mucosa and benign polyps but an abnormal cytoplasmic distribution in carcinomas. Amplification, mutations, and immunohistochemical staining were independent of histologic differentiation, Duke's stage, or DNA ploidy status. This study demonstrates that abnormalities ofrasgenes are a common finding in colorectal carcinomas. They are potentially important biologic changes associated with malignancy, although they do not appear to be related to clinical behavior.

ISSN:0012-3706    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

&NA;To gain a better understanding of the biologic development of rectal adenicarcinomas, the authors evaluated the level ofrasgene protein product (p21) in the available material of 74 Dukes'B adenocarcinomas, 64 Dukes' C adenocarcinomas, and 60 lymph‐node metastases resected at the University of Chicago Medical Center between 1965 and 1981. Pathologic slides and archival paraffin blocks were retrieved for confirmation of the original diagnosis and measurement of p21 content. P21 titers were obtained using the RAP‐5 monoclonal antibody in a semiquantitative immunohistochemical assay. Titer was expressed as the highest dilution giving definitive staining using the avidinbiotin peroxidase method. The analysis indicated that a higher percentage of Dukes' stage C rectal adenocarcinomas had high (≥1:40,000) p21 titers than Dukes' B adenocarcinomas (68.8vs.51.4 percent, respectively,P<0.05). In view of recent data suggesting thatrasoncogene expression confers invasive and metastatic capabilities to NIH 3T3 cells, the authors believe this study offers evidence that overexpression ofrasoncogene with overproduction of p21 protein product may be an important prerequisite for the acquisition of metastatic capabilities in the early stages of colon cancer.

ISSN:0012-3706    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

&NA;Althoughen blocresection for contiguous invasion by adenocarcinoma of the colon is a well‐recognized principle, it is difficult to assess the efficacy of this principle when upper abdominal viscera are involved. This study was undertaken to better define this subgroup. Seventeen patients were studied over a period of 20 years who underwent extended resections for colonic adenocarcinoma with upper abdominal organ invasion. The age range was 30 to 81 years (average, 61 years). There was a male‐to‐female ratio of greater than 2,1. The duration of presenting symptoms was as short as 4 days and as long as 18 months (average, 4.3 months). The most common complaints was weight loss (13/17). The next most common complaint were abdominal pain (10/17), bowel complaints (5/17), and septic symptoms (4/17). A single organ was involved in 7 instances, but multiple organs were involved in most cases. The frequency of involvement was the stomach, spleen, and duodenum (5 each), abdominal wall and diaphragm (4 each), pancreas and liver (3 each). There were 2 perioperative deaths and 9 other major complications. The most common cause of morbidity and mortality was septic in nature in 8 of the 11 instances. All 3 patients with pancreatic resections had postoperative complications; none were fatal. Five patients survived over 10 years, three were 5‐year survivors, and two are living and free of disease at less than 5 years. Excluding the two perioperative deaths, four of the five patients who died in less than 5 years had documented recurrences.

ISSN:0012-3706    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

&NA;The effect of subacute large‐bowel obstruction on the mesenteric circulation was studied in a chronic dog model. Colonic obstruction was produced 40 cm distal to the ileocolic sphincter. Five days later, gut blood flow was measured with 15 &mgr;m microspheres, together with hemodynamic and metabolic values. Two other groups provided comparative data: unoperated animals to measure baseline values and sham‐operative controls. With adequate hydration, hemodynamic and metabolic values remained stable in the experimental group. There was a two‐fold increase (P<0.05) in blood flow in the dilated colon proximal to the obstruction site, whereas blood flow to the other organs remained unchanged. These results have relevance for the hemodynamic management and use of primary anastomosis in patients with large‐bowel obstruction. Furthermore, these data might implicate increased local bowel blood flow as a contributory factor to the poorer long‐term prognosis found in patients with large‐bowel cancer presenting with intestinal obstruction.

ISSN:0012-3706    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

&NA;A prospective study of 18 consecutive patients undergoing unilateral, partial‐thickness, distal, internal sphincterotomy for the treatment of chronic anal fissure was performed. Biopsies were taken from the base of the fissure and from the lateral muscle before division. Normal specimens were taken from the internal anal sphincter of patients undergoing abdominoperineal resection. Specimens confirmed the presence of fibrosis throughout the internal anal sphincter in patients with anal fissures, but none in controls.

ISSN:0012-3706    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

&NA;After a median latency of 2 years, the initial late colorectal radiation injuries in 182 patients were: stricture (37 percent), minor lesions (36 percent), rectovaginal fistula (22 percent), and gangrene or other fistulas (5 percent). Due to progression, new colorectal injuries, primarily stricture (55 percent) and fistula (42 percent), occurred in 68 patients (37 percent). Resection provided the best results. However, the resectability rate was low (46 percent) and resection was primarily performed in patients with a circumscript well‐defined stricture of the proximal rectum or sigmoid colon with an anastomotic leakage rate of 5 percent. The prevailing management of 78 patients with fistula or stricture with synchronous fistula was defunctioning colostomy, primarily end‐sigmoidostomy, providing fair results in half of the patients. Stomal complications occurred in 15 percent. The radiation‐induced colorectal mortality was 8 percent. Colorectal fistula and associated radiation injuries of the urinary tract, and especially of the small bowel, were the major determinants of fatal outcome, yielding an overall radiation‐induced mortality of 25 percent. After a median observation time of 13 years, half of the patients were alive at follow‐up; 56 percent of these had a fair outcome whereas the remaining patients continued to have mild symptoms responding to conservative measures (34 percent) or disabling symptoms (10 percent).

ISSN:0012-3706    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

&NA;Sixteen patients underwent anterior resection and coloanal anastomosis between October 1984 and September 1987. Indications included adenocarcinoma of the low rectum in 9, villous tumor in 2, carcinoid tumor in 1, radiation proctitis in 1, adult onset Hirschprung's disease in 1, rectourethral fistula in 1, and megarectum in 1. There was no in‐hospital mortality and no anastomotic dehiscence. The Kirwan classification was used to evaluate functional results. Ninety‐three percent of patients expressed satisfaction with their surgical results. Eighty‐seven percent of patients are normally continent. A single patient is grossly incontinent. Eight of nine patients with carcinoma were resected for cure. A single patient has died of an unrelated disorder and the remaning seven are free of disease at an average follow‐up of 24 months. The authors conclude that coloanal anastomosis is a safe procedure accompanied by minimal morbidity, or risk of local recurrence. Excellent, or at least acceptable, continence can be anticipated in the majortty of carefully selected patients. The coloanal anastomosis should be strongly considered in any patient with a lowlying rectal lesion in whom body habitus precludes the possibility of conventional low anterior resection.

ISSN:0012-3706    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

&NA;The mechanism by which ureterocolic anastomoses promote cancer of the colon is uncertain. To investigate the role of anastomotic healing, rats were exposed to the colon carcinogen azoxymethane after which they had either 1) a sham operation, 2) colotomy with suture, or 3) colovesical anastomosis, performed randomly. The first two groups had an equally low frequency of colon cancers, whereas rats with colovesical fistulas had a significantly higher frequency, and cancers were concentrated at the anastomotic site. It was concluded that prompt healing does not promote cancer in this model. It is probably not responsible for suture‐line recurrences seen clinically, nor for the increased frequency of cancer at the site of urinary diversion into the colon.

ISSN:0012-3706    

出版商:OVID    

年代:1989

数据来源: OVID