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PubMedDate not supplied

Gastroduodenal and ileal polyps in patients treated surgically for familial polyposis coli with proctocolectomy and continent ileostomy.

Eighteen patients, who previously had been treated surgically for familial polyposis coli with proctocolectomy and a continent ileostomy were re-investigated with endoscopy and X-ray for gastric, duodenal and ileal polyps. Gastric and/or duodenal polyps were found in 6 patients and ileal polyps in 2. Altogether upper GI-polyps were found in 7 patients (39%). Most polyps were true adenomas. In one patient with large gastric adenomas, the severe dysplasia called for a gastric resection. It is obvious that familial polyposis may affect the whole gastro-intestinal tract, therefore necessitating regular surveillance of the upper GI-canal as well as the colon and rectum in patients with this hereditary affliction.

Adenomatous Polyposis Coli↗
PubMedDate not supplied

The distribution of polyps in the large intestine.

The distribution of polyps of the large intestine was investigated. Comparisons were made between results of autopsy studies and a clinical study consisting of 114 consecutively resected polyps. The shift from distal to proximal predominance of adenomas with increasing age from the 50 to the 80 year age group in autopsy studies, was in accordance with the high frequency of adenomas in the distal part of the large intestine in the prospective clinical study, mean 60 years of age. The present clinical study showed a high frequency of adenomas among men, whereas a tendency towards larger polyps and more polyps larger than 10 mm was seen for women. The present examination confirms the reported discrepancy between a high prevalence of adenomas compared to a much lower prevalence of cancer. Thus, the present results emphasize the need for further studies to gain information on risk factors in polyps or individuals predisposed for malignancy of the large intestine.

Aged↗
PubMed1996

The polyp prevention trial I: rationale, design, recruitment, and baseline participant characteristics.

The Polyp Prevention Trial (PPT) is a multicenter randomized controlled trial examining the effect of a low-fat (20% of total energy intake), high-fiber (18 g/1000 kcal), high-vegetable and -fruit (5-8 daily servings) dietary pattern on the recurrence of adenomatous polyps of the large bowel, precursors of most colorectal malignancies. Eligibility criteria include one or more adenomas removed within 6 months of randomization; complete nonsurgical polyp removal and complete colonic examination to the cecum at the qualifying colonoscopy: age 35 years of more; no history of colorectal cancer, inflammatory bowel disease, or large bowel resection; and satisfactory completion of a food frequency questionnaire and 4-day food record. Of approximately 38,277 potential participants with one or more polyps recently resected, investigators at eight clinical centers randomized 2,079 (5.4%; 1,037 in the intervention and 1,042 in the control arm) between June 1991 and January 1994, making the PPT the largest adenoma recurrence trial ever conducted. Of PPT participants, 35% are women and 10% are minorities. At study entry, participants averaged 61.4 years of age; 14% of them smoked, and 22% used aspirin. At the baseline colonoscopy, 35% of participants had two or more adenomas, and 29% had at least one large (> of = 1 cm) adenoma. Demographic, behavioral, dietary, and clinical characteristics are comparable across the two study arms. Participants have repeat colonoscopies after 1 (T(1)) and 4 (T(4)) years of follow-up. The primary end point is adenoma recurrence; secondary end points include number, size, location, and histology of adenomas. All resected lesions are reviewed centrally by gastrointestinal pathologists. The trial provides 90% power to detect a reduction of 24% in the annual adenoma recurrence rate. The primary analytic period, on which sample size calculations were based is 3 years (T(1) to T(4)), which permits a 1-year lag time for the intervention to work and allows a more definitive clearing of lesions at T(1), given that at least 10-15% of polyps may be missed at baseline. The final (T(4)) colonoscopies are expected to be completed in early 1998.

Adenoma↗
PubMed1997

Expression of E-cadherin-associated molecules (alpha-, beta-, and gamma-catenins and p120) in colorectal polyps.

E-cadherin and its associated cytoplasmic proteins alpha-, beta-, and gamma-catenin and p120 protein play a crucial role in the maintenance of normal tissue architecture. Perturbation in any of these molecules results in loss of intercellular adhesion and cell transformation. In this study, we have used immunohistochemistry to localize E-cadherin, alpha-, beta-, and gamma-catenin, and p120 in paraffin-embedded tissues from 60 patients with colonic polyps. Specimens consisted of 20 samples each from hyperplastic, inflammatory, and sporadic adenomatous polyps. Ten histologically normal colonic samples were also studied. Normal colonic epithelial cells showed strong E-cadherin/ catenin/p120 immunostaining at the cell-cell junction. In 65% (13/20) of adenomatous polyps, beta-catenin showed abnormal nuclear localization with increased expression and loss of membranous staining compared with the adjacent normal mucosa. In two cases (10%), gamma-catenin was seen in the nuclei. Heterogeneous p120 immunoreactivity was observed in four cases (20%), of which two also showed beta-catenin nuclear localization. Preserved membranous alpha-catenin staining was seen in all cases. E-cadherin was down-regulated in 6 of 20 (30%) adenomas with loss of cell surface staining in 3 cases. All hyperplastic and 40% (8/20) of inflammatory polyps showed weak E-cadherin expression on the surface epithelium. Similar changes in p120 expression were seen in all hyperplastic and 20% (4/20) of inflammatory polyps. There were no concomitant changes in alpha-, beta-, or gamma-catenin expression. These results indicate that changes in catenin expression and cellular localization occur early in dysplastic colonic lesions.

Adenomatous Polyps↗
PubMedDate not supplied

[Morphological characteristics of hyperplastic and adenomatous stomach polyps].

A morphological study of biopsy samples of gastric polyps from 224 patients was carried out. Four stages in gastric polyp morphogenesis were distinguished: foveolar hyperplasia, hyperplastic polyp, "two-floor" adenoma and adenoma. The correlation was established between the degree of Helicobacter pylori infection in the polyp mucous membrane on the one hand, and epithelial and stromal reactions (immuno-inflammatory reaction of stroma, chronic inflammation, formation of Russel bodies, cystes and chronic erosions) on the other. Greater content of stromal collagens, type IV collagen in case of gastric hyperplastic lesions was observed. Appearance and progression of gastric adenomatous growth in hyperplastic polyp correlates with an increase of type III collagen content, decrease of types I, IV, V collagens and fibronectin.

Adenomatous Polyps↗
PubMed2003

Colon polyp recurrence in a managed care population.

BACKGROUND: Detection, treatment, and subsequent screening of patients with colorectal polyps have considerable implications for public health. Understanding the natural history of colorectal polyps from biologic and health care services standpoints is critical in determining optimal treatment. METHODS: Using computerized data from a large Midwestern health maintenance organization, we identified patients 50 years or older who underwent a polypectomy (index polypectomy) between January 1, 1989, and December 31, 1999. We followed up patients to identify subsequent polypectomies through September 1, 2001. RESULTS: Our final study sample consisted of 8865 individuals with an index polypectomy. Overall, 2704 patients (30.5%) were diagnosed as having recurrent polyps. Kaplan-Meier projections estimate that 50% of patients will have a recurrence within 7.6 years (95% confidence interval [CI], 7.2-8.1 years). Among patients who underwent colon screening at least 9 months after the index polypectomy (52% of original cohort), Kaplan-Meier projections estimate that 50% will have a recurrent polyp within 3.9 years (95% CI, 3.8-4.1 years). CONCLUSIONS: The results demonstrate that, even when screening and treatment are received by those who need it, the risk of colon polyp recurrence is high and many patients do not undergo additional screening. Efforts to increase and monitor ongoing screening of postpolypectomy patients are warranted. In addition, further research is needed to better identify patients at risk for recurrence so that continued screening and other interventions can be targeted at these groups.

Aged↗
PubMed1998

Expression of the transforming growth factor beta isoforms in inflammatory cells of nasal polyps.

OBJECTIVE: To determine the expression and the potential role of transforming growth factor beta (TGF-beta) in nasal polyposis. DESIGN: Comparison of TGF-beta expression between normal and inflammatory nasal mucosa and polyps; in inflammatory nasal polyps, characterization of the TGF-beta isoforms expression and their potential location in macrophages and eosinophils. SETTING: Patients and samples were selected at the Hôpital Intercommunal, Créteil, France, and immunohistochemistry and immunoblots were performed at the Institut National de la Sante et de la Recherche Medicale U296 (Universite Paris XII, France). SUBJECTS: Nasal polyps and nasal mucosa were sampled in 21 patients during ethmoidectomy, and muscosa was sampled in 6 healthy patients during rhinoplasty. METHODS: Immunohistochemistry and Western blot analysis were performed using specific antibodies to TGF-beta1-3, TGF-beta1, TGF-beta2, and TGF-beta3 isoforms. Double labeling was also performed using anti-TGF-beta1 antibody together with macrophages or eosinophil-specific antibodies. RESULTS: The expression of TGF-beta(1-3) was significantly higher in inflammatory nasal polyps than in inflammatory nasal mucosa and higher in inflammatory nasal mucosa than in nasal mucosa from healthy patients. Transforming growth factor beta1 was the main isoform detected in inflammatory nasal polyps, and it was present in numerous macrophages and in some eosinophils. CONCLUSIONS: Transforming growth factor beta, mainly TGF-beta1, is strongly expressed in inflammatory nasal mucosa, where it could be produced by macrophages and eosinophils. Transforming growth factor beta could induce epithelium and connective tissue modifications and therefore be involved in the pathogenesis of nasal polyposis.

Adult↗
PubMed1990

Endoscopic transnasal surgery in antrochoanal polyp.

The current treatment of antrochoanal polyp is simple avulsion of the nasal part with or without removal of the antral part. The antral part is removed through a Caldwell-Luc antrostomy, inferior meatal antrostomy, or middle meatal antrostomy. In this study, endoscopic surgery was performed in 22 cases of antrochoanal polyps where the antral part was removed through the middle meatus. Two new instruments were designed to help complete removal of the antral part of the polyp through the maxillary ostium. Some points of controversy concerning the antrochoanal polyp are discussed according to the diagnostic and therapeutic endoscopic findings. Endoscopic follow-up of these cases for periods ranging between 6 and 30 months, with an average of 20 months, showed no recurrence. It was concluded that endoscopic surgery of the antrochoanal polyp through the middle meatus could be performed as an outpatient procedure, and is safe and reliable.

Adolescent↗
PubMed1998

Risk of colon cancer associated with a family history of cancer or colorectal polyps: the diet, activity, and reproduction in colon cancer study.

The Diet, Activity, and Reproduction in Colon Cancer (DARCC) study is a large, multi-center case-control study of colon cancer. We examined family histories of cancer among first-degree relatives obtained by computer-assisted in-person interviews from the DARCC to study the impact of family histories of several cancers and colorectal polyps on colon cancer risk. We examined familial cancer risks both by treating a family history of polyps or cancer as a covariate in a logistic regression model, and by comparing cancer or polyp incidence among relatives of cases to incidence among relatives of controls in a proportional hazards model. There were few differences between the odds ratios (OR) or confidence intervals (CI) generated from logistic regression models and the hazard rate ratios (HRR) generated from the proportional hazards models. Overall, the OR of colon cancer among subjects with a family history of colorectal cancer was 1.77. There were only minor differences in risk by sex, age and subsite. A family history of colorectal polyps also increased risk by about the same amount as a family history of colorectal cancer. The increased risk associated with a family history of polyps did not appear to decrease with age.

Adult↗
PubMed1977

Colorectal polyps and carcinoma in Southern Iran.

A study was made of the prevalence of colorectal polyps (excluding juvenile polyps, familial polyposis coli and villous adenomas) and the minimum frequency of colorectal carcinoma in Southern Iran. A total of 801 large intestines from necropsies performed on individuals 20 years or older was examined with or without magnifying lens for presence of polyps. Our prevalence rate was then compared with those reported on postmortem material from the USA, Australia, South Africa (Bantus), Colombia, and Hawaii (Japanese immigrants). Our surgical pathology files were reviewed for colorectal polyps over a 22-year period (1952-1973). Colorectal carcinomas diagnosed in the Department of Pathology were reviewed over 11 years (1963-1973) and the minimum frequency rates compared with corresponding age- and sex-specific incidence rates from Connecticut, USA. The data indicate 1) a very low prevalence rate for colorectal polyps as well as carcinoma in our region and 2) a rather striking predominance of right-sided colonic carcinoma.

Adenocarcinoma↗
PubMed1981

Tumor-associated antigens in polyps and carcinoma of the human large bowel.

The presence of a number of tumor-associated antigens was studied in eight metaplastic polyps, 22 tubulovillous adenomas, and 20 carcinomas. Specific tumor antigens were identified using the immunohistochemical (P.A.P.) technique to detect carcinoembryonic antigen (CEA), human placental lactogen (HPL), alphafetoprotein (AFP), colon-specific antigen (CSA), pregnancy-specific beta lipoprotein 1 (SP1), human beta chorionic gonadotropin (beta hCG), and placental alkaline phosphatase (P Alk P), isoferritins (FE), and transferrin (TF). There is no difference in either the number of antigens present or the number of cases positive for each antigen in cancers and tubulovillous adenomas, but the majority of metaplastic polyps show only CEA and HPL positivity. The two metaplastic polyps showing a full range of positivity were atypical and over 5 mm in diameter. The findings have shown a remarkable similarity between polyps and cancer, which strengthens the concept of the relationship between adenomatous polyps and carcinoma of the colon.

Adenoma↗
PubMed1981

A comparative ultrastructural study of hyperplastic and adenomatous polyps, incidental and in association with colorectal cancer.

Adenomatous polyps of the colon were examined by light and electron microscopy in high risk patients having synchronous carcinoma and in low risk patients having incidental polyps only. There was no difference between these groups when polyp size, degree of dysplasia, and pattern of growth were correlated at light microscopic level. However, the groups differed ultrastructurally; the synchronous polyps showed atypical features, characterized in particular by abnormal secretory droplets and increased numbers of undifferentiated cells. Hyperplastic polyps were also included in the study and showed no atypia. Previously, adenomas from cases of familial polyposis coli have been shown to contain similar abnormal secretory droplets, and it is suggested that this ultrastructural change may be an important marker of early malignancy. Histochemistry and immunohistology may help to characterize the secretory material further.

Adult↗
PubMed1982

The prevalence of polyps of the large intestine in Oslo: an autopsy study.

The colon and rectum were removed from 445 consecutive autopsies and examined for the presence of polypoid lesions under an illuminating magnifying lens. There were seven clinically undiagnosed carcinomas, 329 adenomas, 174 hyperplastic polyps, 59 mucosal tags, 34 other polypoid lesions, and 54 polyps in which no histologic diagnosis could be made. Adenomas were present in 34% of the men and 32% of the women. The adenoma prevalence rate increased smoothly with age in men, whereas the rate in women showed a biphasic variation with a peak at 50--59 years followed by a second increase after 70 years of age. The distribution of adenomas within the bowel showed a marked change with age, from a moderate left-sided predominance before 60 years of age to a marked right-sided predominance in patients over 80 years of age, particularly in men. Hyperplastic polyps were present in 27% of the men and 18% of the women. In men, their frequency and distribution within the bowel showed similar changes with age as were seen for the adenomas. In women, no such age-dependency was observed for hyperplastic polyps. Multiplicity of polyps increased with age and was more pronounced in men than in women. Adenomas in women tended to be larger, more atypical, and more villous than in men. A comparison with a similar study from Northern Norway showed no difference in the prevalence of adenomas in spite of a 70% higher incidence rate for colorectal cancer in Oslo.

Adenoma↗
PubMed1991

Pattern of cell kinetics in colorectal mucosa of patients with different types of adenomatous polyps of the large bowel.

It is generally accepted that adenomatous polyps represent the natural precursor of many colorectal malignancies. The sequence, however, which leads from a normally appearing mucosa to cancer is complex and involves many steps, including a hyperproliferative mucosa with an upward expansion of the replicative compartment. The current study evaluates cell replication in normal colorectal mucosa of patients with adenomatous polyps of various types and relates the observed findings to the main clinical and morphologic features of adenomas. Forty-four patients with polyps and 27 controls entered the study. Samples of colorectal mucosa were taken at endoscopy and cell replication was evaluated with a standard autoradiographic procedure. Cell replication was expressed as labeling index (LI), in the whole crypt and in each of the five longitudinal compartments in which the crypts were divided. Total LI and LI per crypt compartment were significantly higher (P less than 0.02 and P less than 0.01, respectively) than in controls. There was no appreciable difference of LI values between patients with single or multiple, tubular or tubulovillous, small or large adenomas, but in all of these subgroups LI was significantly higher than in controls. In conclusion, in normally appearing colorectal mucosa of patients with adenomatous polyps there was a significant increase of cell replication and a marked upward expansion of the proliferative zone; these changes were more evident in the left colon and in the rectum. Finally, cell replication did not seem to be related to the number of polyps, to the most common histotypes, or to the pattern of recurrence.

Adult↗
PubMed2001

Risk factors of endometrial polyps resected from postmenopausal patients with breast carcinoma treated with tamoxifen.

BACKGROUND: Endometrial polyps are the most common endometrial pathology described in association with postmenopausal tamoxifen exposure. Up to 3% of these polyps may show malignant changes. However, to the authors' knowledge no one has described any risk factor for the development of this pathology in postmenopausal patients with breast carcinoma treated with tamoxifen. OBJECTIVE. The objective of this study was to evaluate whether risk factors can be identified for the development of endometrial polyps in postmenopausal patients with breast carcinoma treated with tamoxifen. METHODS: The authors reviewed the medical records of 54 postmenopausal patients with breast carcinoma in whom endometrial polyps were resected by hysteroscopy after at least 6 months of tamoxifen treatment (Group I). Demographic characteristics, health habits, risk factors for endometrial carcinoma, and clinical factors related to the primary breast disease were examined. The results were compared with those obtained from 210 similar patients in whom hysteroscopy did not reveal any endometrial pathology (Group II). RESULTS: Age at menopause was significantly older, duration of breast disease was significantly longer, and body weight was significantly heavier among Group I patients compared with Group II patients (P = 0.0162, P = 0.0026, and P = 0.0364, respectively). Endometrial thickness, measured by transvaginal ultrasonography, was significantly thicker in Group I patients (16.3 +/- 7.2 mm) compared with that detected in Group II patients (11.8 +/- 6.3; P = 0.0001). CONCLUSIONS: Various factors, such as older age at menopause, longer duration of breast disease, heavier weight, and thicker endometrium may contribute to the prediction of increased risk of development of endometrial polyps in postmenopausal patients with breast carcinoma treated with tamoxifen.

Antineoplastic Agents, Hormonal↗
PubMed2004

Dietary calcium supplementation for preventing colorectal cancer and adenomatous polyps.

BACKGROUND: Several dietary factors have been considered to be involved in the increasing incidence of colorectal cancer in industrialised countries. Experimental and epidemiological evidence has been suggestive but not conclusive for a protective role for high dietary calcium intake. Intervention studies with colorectal cancer as an endpoint are difficult to perform owing to the large number of patients and the long follow-up required; studies using the appearance of colorectal adenomatous polyps as a surrogate endpoint are therefore considered in reviewing the existing evidence. OBJECTIVES: This systematic review aims to assess the effect of supplementary dietary calcium on the incidence of colorectal cancer and the incidence or recurrence of adenomatous polyps. SEARCH STRATEGY: We searched the Cochrane Controlled Trials Register, the Cochrane Colorectal Cancer Group specialised register, MEDLINE, Cancerlit, and Embase, to April 2002. The reference lists of identified studies were inspected for further studies, and the review literature was scrutinized. SELECTION CRITERIA: Randomised controlled trials of the effects of dietary calcium on the development of colonic cancer and adenomatous polyps in humans are reviewed. Studies of healthy adults and studies of adults at higher risk of colon cancer due to family history, previous adenomatous polyps, or inflammatory bowel disease were considered; data from subjects with familial polyposis coli are excluded. The primary outcomes were the occurrence of colon cancer, and occurrence or recurrence of any new adenomas of the colon. Secondary outcomes were any adverse event that required discontinuation of calcium supplementation, and drop-outs before the end of the study. DATA COLLECTION AND ANALYSIS: Two reviewers independently extracted data, assessed trial quality and resolved discrepancies by consensus. The outcomes were reported as odds ratios (OR) with 95% confidence intervals (CI). The data were combined with the fixed effects model. MAIN RESULTS: Two studies with 1346 subjects met the inclusion criteria. Both trials were well designed, double - blind, placebo controlled trials, included participants with previous adenomas. The doses of supplementary elemental calcium used were 1200 mg daily for a mean duration of 4 years, and 2000 mg/day for three years. The rates of loss to follow -up were 14 % and 11%. For the development of recurrent colorectal adenoma, a reduction was found (OR 0.74, CI 0.58,0.95) when the results from both trials were combined. REVIEWER'S CONCLUSIONS: Although the evidence from two RCTs suggests that calcium supplementation might contribute to a moderate degree to the prevention of colorectal adenomatous polyps, this does not constitute sufficient evidence to recommend the general use of calcium supplements to prevent colorectal cancer.

Adenoma↗
PubMed2005

Dietary calcium supplementation for preventing colorectal cancer and adenomatous polyps.

BACKGROUND: Several dietary factors have been considered to be involved in the increasing incidence of colorectal cancer in industrialised countries. Experimental and epidemiological evidence has been suggestive but not conclusive for a protective role for high dietary calcium intake. Intervention studies with colorectal cancer as an endpoint are difficult to perform owing to the large number of patients and the long follow-up required; studies using the appearance of colorectal adenomatous polyps as a surrogate endpoint are therefore considered in reviewing the existing evidence. OBJECTIVES: This systematic review aims to assess the effect of supplementary dietary calcium on the incidence of colorectal cancer and the incidence or recurrence of adenomatous polyps. SEARCH STRATEGY: We searched the Cochrane Controlled Trials Register, the Cochrane Colorectal Cancer Group specialised register, MEDLINE, Cancerlit, and Embase, to April 2002. The reference lists of identified studies were inspected for further studies, and the review literature was scrutinized. SELECTION CRITERIA: Randomised controlled trials of the effects of dietary calcium on the development of colonic cancer and adenomatous polyps in humans are reviewed. Studies of healthy adults and studies of adults at higher risk of colon cancer due to family history, previous adenomatous polyps, or inflammatory bowel disease were considered; data from subjects with familial polyposis coli are excluded. The primary outcomes were the occurrence of colon cancer, and occurrence or recurrence of any new adenomas of the colon. Secondary outcomes were any adverse event that required discontinuation of calcium supplementation, and drop-outs before the end of the study. DATA COLLECTION AND ANALYSIS: Two reviewers independently extracted data, assessed trial quality and resolved discrepancies by consensus. The outcomes were reported as odds ratios (OR) with 95% confidence intervals (CI). The data were combined with the fixed effects model. MAIN RESULTS: Two studies with 1346 subjects met the inclusion criteria. Both trials were well designed, double - blind, placebo controlled trials, included participants with previous adenomas. The doses of supplementary elemental calcium used were 1200 mg daily for a mean duration of 4 years, and 2000 mg/day for three years. The rates of loss to follow -up were 14 % and 11%. For the development of recurrent colorectal adenoma, a reduction was found (OR 0.74, CI 0.58,0.95) when the results from both trials were combined. AUTHORS' CONCLUSIONS: Although the evidence from two RCTs suggests that calcium supplementation might contribute to a moderate degree to the prevention of colorectal adenomatous polyps, this does not constitute sufficient evidence to recommend the general use of calcium supplements to prevent colorectal cancer.

Adenoma↗
PubMed2004

Genetic conditions associated with intestinal juvenile polyps.

Juvenile polyps are hamartomatous polyps found primarily in infants and children, and in association with juvenile polyposis (JP; OMIM #174900), Cowden syndrome (CS; OMIM #158350), and Bannayan-Riley-Ruvalcaba syndrome (BRRS; OMIM# 153480). Although solitary juvenile polyps are benign lesions, when present in JP patients they may lead to gastrointestinal cancers. Germline mutations in MADH4 and BMPR1A predispose to JP, and both genes are involved in TGF-beta superfamily signaling pathways. In CS and BRRS, juvenile polyps are a less consistent feature, and CS patients are at risk for breast and thyroid cancers. Mutations of the tumor suppressor gene PTEN have been found in the germline of both CS and BRRS patients. Despite different underlying genetic mechanisms, these and other syndromes share the same phenotypic feature of juvenile polyps.

Animals↗