PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Colonic Polyps”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 487 records · Page 27Linked to original sources
PubMed2004

Colon polyps and cancer.

Screening for colorectal neoplasia still is the best method of reducing the mortality due to colorectal cancer, and it is to be hoped that fecal occult blood test programs will expand in the near future and be combined with appropriate endoscopy. There are substantial problems with compliance in large programs with occult blood tests as well as endoscopy. Colonography and DNA testing in feces are not yet suitable for population screening. Diagnostic strategies in symptomatic patients are becoming more selective, in the hope of avoiding many superfluous examinations without increasing the risk of missing cancers. New results have confirmed the preventive effect of long-term aspirin use on adenoma recurrence, but the most cost-effective dosage is not clear; the mechanism of action is also uncertain, but seems to involve cyclooxygenase-2. The risk of adenomas does not appear to be associated with low consumption of folate, but with low intake of fiber. A number of biomarkers have been evaluated in polyp patients, but so far surveillance is still based on endoscopic experience, which is less than optimal. Attempts have been made to restrict the number of surveillance endoscopies and reduce the pathologist's workload. The place of argon plasma coagulation has been clearly defined in connection with piecemeal removal of large sessile adenomas. Advances have been achieved in surgery and radiotherapy for rectal cancer, and acute surgery for colonic cancer with severe obstruction will be less common after the introduction of the metal stent.

Clinical Trials as Topic↗
PubMedDate not supplied

[Colonic polyps. Experience at a clinical center in Caracas].

After six years experience in the anatomopathological study and having checked 33.452 histological cases 772 corresponded to colon tumoral pathology. It was then decided to proceed with the epidemiological analysis of the polyps, it's anatomical distribution according to sex and age, it's histolopathological characteristics and the possible relationship with malignant transformation. We found a clear predominance mainly of adenomatosic neoplasic polyps, followed by hyperplasic polyps. 65% of the patients were male and more than half of the cases were between the ages of 50 and 70. Coincitentally, 86% of the atypical polyps were found within this age group.

Adenoma, Villous↗
PubMed2005

Preoperative colonoscopy decreases the need for laparoscopic management of colonic polyps.

PURPOSE: Patients are commonly referred to surgeons for surgical resection of polyps that cannot be excised colonoscopically. Repeating the colonoscopy may be met with resistance by both the patient and the referring endoscopist. However, there are two distinct benefits. First, if the lesion was not marked, tattooing facilitates laparoscopic resection. Second, and more importantly, many of these polyps can be removed endoscopically by an experienced colorectal surgeon, avoiding unnecessary colon resection. Over a period of five years, we have reviewed preoperative colonoscopy in patients who were referred for surgical treatment of benign polyps. METHODS: From January 1999 through September 2003 all patients referred for surgical resection of a benign polyp were consecutively entered into a database by a single group of colorectal surgeons. All patients underwent preoperative colonoscopy on the day before the planned colon resection. Patient charts were reviewed, and demographics were recorded. The referral and preoperative colonoscopy reports and all pathology results were reviewed to record the polyp size, location, histology, and subsequent treatment. RESULTS: Altogether, 71 patients were included in this study. The average size of the polyps was 24 mm (range, 10-60 mm). The location of the polyp as determined by preoperative colonoscopy differed from the location noted on referral colonoscopy in nine patients (13 percent). Surgery was canceled in 23 patients (32 percent), primarily because of complete polypectomy at preoperative colonoscopy. Of the 48 who underwent surgery, 23 (47 percent) had a colonic tattoo placed, at the discretion of the surgeon. Lesions clearly located in the cecum were not tattooed routinely. Of the 48 patients who underwent surgery, 45 (94 percent) underwent laparoscopic colon resection. CONCLUSIONS: We concluded that patients referred for surgical resection of a polyp should undergo repeat colonoscopy preoperatively, given that in our study one-third of patients were spared unnecessary colectomy. In addition, repeat endoscopy by the operating surgeon offers an opportunity to confirm the location of the lesion and place a colonic tattoo to facilitate laparoscopic resection.

Aged↗
PubMed1989

[The Nd: YAG laser in the treatment of colonic polyps].

The result of Nd: YAG laser therapy in 31 patients with pathologically verified rectosigmoid polyps was presented. Except one case with large adenomatous polyp recurring two months after the primary treatment, all other patients were cured clinically on their first therapy. There were no severe complications, and the longest follow-up period was 14 months. The authors came to the conclusion that compared with other modalities, Nd: YAG laser therapy is safe, effective, and low recurrence rate.

Colonic Polyps↗
PubMed1987

The 'malignant colon polyp'. A critique and opinion.

There is some controversy about the indications for surgical resection above the distal rectum following colonoscopic removal of a polyp which proves to be malignant. Sessile, villous adenomas are generally considered to carry greater risk of spreading malignancy than pedunculated, tubular or villous adenomas. Resection is usually recommended in the presence of carcinomatous invasion beyond the muscularis mucosae and/or insufficient tumor-free margin of the stalk if the patient's condition permits.

Carcinoma in Situ↗
PubMed1999

Colon polyps: a damaged developmental system and a precursor to cancer.

The observation that the attenuated form of adenomatous polyposis coli (AAPC) has a different mutational spectrum in both the adenomatous polyp and the carcinoma than the classical form of APC has led to the hypothesis that AAPC alleles retain some residual APC activity associated with a greatly reduced number of polyps. It is suggested that further progression to carcinoma may be dependent upon either loss of the AAPC allele (loss of heterozygosity), followed by an APC mutation in the wild-type allele, or the occurrence of APC mutations within both the AAPC and wild-type alleles.

Adenomatous Polyposis Coli↗
PubMed1979

[Large colonic polyp: endoscopic or surgical removal?].

93 neoplastic polyps measuring more than 2 cm in diameter have been removed from the colon by endoscopy. 15% of the polyps showed severe atypia (focal carcinoma), and in 15% an invasive carcinoma was found. Polypectomy was complicated in 14 cases by bleeding, in 12 cases it was cured by endoscopy. In 1 case in which the colon was injured by coagulation the lesion healed spontaneously. The surgery rate due to complications of the endoscopic removal procedure or due to invasive carcinoma was 7% for the polyps with a diameter of 2-3 cm, 15% for those of 3-5 cm and 50% for polyps with a diameter of more than 5 cm. It is therefore suggested that neoplastic polyps of more than 5 cm in diameter should be removed by endoscopy in high risk patients only.

Carcinoma↗
PubMed1989

Ultrastructure of the absorptive cell glycocalyx in hyperplastic colonic polyps after staining with alcian blue and high iron diamine.

The glycocalyx of absorptive cells in large intestinal hyperplastic polyp was characterized histochemically at the electron microscope level by the use of the Alcian Blue pH 2.5 and high iron diamine techniques with the aim of comparing their ability in preserving the fine reticular network of the structure. Both the reagents stained glycocalyx, indicating the presence of sulphated acidic glycoconjugates. However, they showed different degrees of condensation of the reactive sites. Alcian Blue preserved its filamentous appearance better.

Alcian Blue↗
PubMed1994

Yield of rescreening for colonic polyps using flexible sigmoidoscopy.

OBJECTIVE: To determine the yield of performing screening-flexible sigmoidoscopy 1 yr after a negative examination. METHODS: In a flexible sigmoidoscopy screening program at a chemical factory, over a period of 3 yr, 307 sigmoidoscopies were performed by a single endoscopist in workers greater than or equal to 40 yr old. Of 202 workers screened in the first 2 yr, 32% were found to have polyps (mean age, 52.9 yr). Repeat flexible sigmoidoscopy was recommended to all workers after 1 yr, and 81 complied. RESULTS: The mean (+/- SEM) time to follow-up was 17.0 +/- 0.7 months; of 69 workers who were negative on the first exam, five (7.2%) had a polyp at follow-up. Two of the five patients with polyps were under the age of 50. Of 12 workers who had polyps on the index exam and requested a repeat flexible sigmoidoscopy a yr later, four (33%) again had a polyp. Colonoscopy had been performed in the time interval between the two sigmoidoscopies in 10 of the 12 workers; four (33%) had recurrent polyps. CONCLUSIONS: We conclude that a significant yield of polyps (7.2%) may be found on repeat flexible sigmoidoscopy despite a negative examination within the prior 2 yr. Although the overall yield in this study population was reduced from 32% to 7% by repeat screening, this study supports older American Cancer Society guidelines i.e., to repeat flexible sigmoidoscopy at 1 yr in patients whose first examination was negative. Because half of the positive workers were under age 50, this study also suggests that the American Cancer Society age cutoff may be too stringent.

Chemical Industry↗
PubMed1988

[Malignant colonic polyps: is polypectomy adequate treatment?].

The management of patients with endoscopically removed malignant intestinal polyps is controversial. The risk of residual disease should be assessed against the risk of a surgical operation. The authors report 35 cases of malignant polyps (5.5% of 641 colonoscopically removed adenomas). Sixteen patients had carcinoma in situ and received no further treatment and 19 had invasive carcinoma (sessile in 6, pedunculated in 13). Of these 19, 7 did not undergo surgery--because of old age in 2, minimal invasion in 3, a low rectal location in 1 and refusal in 1. Twelve patients (3 with sessile, 9 with pedunculated polyps) underwent a surgical resection, and residual disease was present in 3 (25%), 1 with positive nodes. Reported criteria of increased risk of residual disease--cancer in lymphatics or veins, incomplete excision, tumour at resection margin, sessile and villous tumours--were present in nine. All three patients with residual disease had microscopically involved margins of resection. The authors believe that the increased risk of recurrence justifies the risk associated with subsequent surgical resection unless the patient is otherwise a poor operative risk.

Adenoma↗
PubMed1997

[Myelodysplastic syndrome associated with gastric cancer and colon polyp].

A 62-year-old man was found to have myelodysplastic syndrome (MDS) and gastric cancer. Serum studies revealed hypogammaglobulinemia, and positive reactions to rheumatoid test and anti-nuclear antibody. Chromosomal analysis of the bone marrow revealed deletions of No. 5 and 7 chromosomes and that of the stomach showed complex abnormalities. It may be hypothesized that an initial event which selects a clone of stem cells could manifest with this sort of immunological abnormalities. Subsequent deranged immunosurveillance may be responsible for the increased risk of cancer. Alternatively an increased chromosomal instability which seems to be associated with immunodeficiencies might be responsible for cancer development.

Anemia, Refractory, with Excess of Blasts↗
PubMed2001

Colon polyps and cancer.

During 1999-2000, a number of important issues related to endoscopy and colorectal polyps and cancer were investigated. Several papers consider whether flat adenomas with high malignant potential are as common in the West as in Japan. Clinical series indicate that signs of rectal bleeding are more predictive of colorectal cancer than gastrointestinal symptoms. Colonoscopy is more accurate than double-contrast barium enema for detecting polyps, and virtual colonoscopy is a promising new diagnostic and screening technique. Primary prevention dietary studies using adenoma recurrence as an end point yield negative results. Surveillance colonoscopy protects individuals in families with hereditary nonpolyposis colorectal cancer, but gastroenterologists continue to perform cancer surveillance in patients with ulcerative colitis in an inconsistent manner. Screening for colorectal neoplasia with fecal occult blood tests and flexible sigmoidoscopy is being better defined and promoted, although many now advocate direct colonoscopy screening based on increasing indirect evidence of efficacy. Better methods of treating large sessile neoplasms are being developed and evaluated, and follow-up surveillance for adenoma patients increasingly is being tailored to individual patient risk.

Colonic Neoplasms↗
PubMedDate not supplied

[Morphological features of juvenile colon polyps in children].

Histological, histochemical and immunohistochemical studies of 50 solitary juvenile polyps (JP) and 50 JP from children with juvenile polyposis syndrome (JPS) were performed. Observations of the focal complex glandular structures with high mitotic rate were more frequent in JP from patients with JPS (n = 29, 58%) than in solitary JP (n = 17, 34%) (p < 0.03). The immunohistochemical study demonstrated p53 overexpression in individual cells and more than 50% of Ki-67-positive cells in 5 (10%) solitary JP and in 17(34%) JP from patients with JPS (p < 0.007). The finding of microglandular pattern is more typical for JP from patients with JPS. Pathological data, expression of p53 and Ki-67 by immunohistochemistry could help to pick out the group of JP with dysplastic changes.

Adenomatous Polyposis Coli↗
PubMed2000

Proteomic analysis of colonic crypts from normal, multiple intestinal neoplasia and p53-null mice: a comparison with colonic polyps.

In order to observe cellular changes caused by mutation of the tumor suppressors, APC and p53, we have generated protein expression profiles of mouse colon epithelial cells using two-dimensional electrophoresis (2-DE). Crypts, polyps and stroma were isolated from normal, multiple intestinal neoplasia (MIN) and p53-null mice, each with a C57Black/6J background, and subjected to 2-DE in two separate pH ranges (pH 3-10 and pH 6-11). No significant differences in protein expression patterns were observed between the normal, MIN and p53-null colon epithelial crypts. However, 64 proteins from the MIN polyps showed a 2-fold or greater difference in intensity that was statistically significant as assessed by the Wilcoxon rank-sum test (p < or = 0.05). Of these, calreticulin, carbonic anhydrase I and a new member of the glutathione-S-transferase theta family of proteins have so far been identified using an in-gel digestion protocol coupled with reversed-phase high performance liquid chromatography (RP-HPLC) ion-trap mass spectrometry. In addition, 38 marker proteins have been identified in a continuing effort to generate a comprehensive 2-DE database of proteins expressed by mouse colon epithelial cells (these databases are available at http://www.ludwig.edu.au/jpsl/jpslhome. html).

Animals↗