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PubMed1990

Mixed hyperplastic adenomatous polyps/serrated adenomas. A distinct form of colorectal neoplasia.

We present the clinicopathologic characteristics of 110 colorectal mixed hyperplastic adenomatous polyps (MHAP) that exhibited the architectural but not the cytologic features of a hyperplastic polyp. They are compared with 60 traditional adenomas, 40 hyperplastic polyps, and five colonic polyps that contained admixed but well-defined hyperplastic and adenomatous glands (HP/AD). The patients with MHAP ranged in age from 15 to 88 years (mean, 63 years). Five patients had two or more (up to seven) lesions. MHAP measured 0.2-7.5 cm in diameter. They were distributed throughout the colorectum, but a slight preponderance of large lesions (more than 1.0 cm) occurred in the cecum and appendix. All MHAP were characterized by a serrated glandular pattern simulating that seen in hyperplasia (27% of MHAP were initially diagnosed as hyperplastic polyps). However, MHAP were distinguished by the presence of goblet cell immaturity, upper zone mitoses, prominence of nucleoli, and the absence of a thickened collagen table. Although surface mitotic activity, nuclear pseudostratification, and nuclear cytoplasmic ratio were greater in MHAP than in hyperplastic polyps, they were slightly less than in traditional adenomas. Thirty-seven percent of MHAP contained foci of significant dysplasia; 11% contained areas of intramucosal carcinoma. We conclude that these lesions reflect a morphologically unique variant of adenoma and suggest that they be termed "serrated adenoma" in order to emphasize their neoplastic nature. We further offer the hypothesis that MHAP may arise from the neoplastic transformation of a more differentiated cell in the crypt than the traditional adenoma.

Adenoma↗
PubMed1993

Chromosome analysis of adenomatous polyps of the colon: possible existence of two differently evolving cytogenetic groups.

A chromosomal study of 42 colonic adenomatous polyps was performed using a technique of direct chromosome analysis derived from the prenatal procedure for diagnosing chromosomal alterations from chorionic villi sampling. Abnormal karyotypes were found in 22 cases. Trisomy 7, the most frequently found alteration, was found in 13 cases, followed by trisomy 13 (nine cases). Monosomy 18 was observed in two cases; in one of these, that of a polyp which had degenerated into an intra-mucosal adenocarcinoma, it was associated with 17p monosomy. Interestingly, these two types of alterations (trisomy 7 versus 18 and 17p monosomy) were not found together in the same lesion. This suggests that there could be two distinct chromosomal behaviors which might be related to the two cytogenetic groups described for colorectal adenocarcinoma. However, the respective frequencies of such cytogenetic groups varied inversely between adenomas and adenocarcinomas, thus suggesting that they evolve differently.

Adult↗
PubMed2003

[Expression of P27 protein and cyclin E in colon cancer].

BACKGROUND & OBJECTIVE: P27 protein and cyclin E were negative cell cycle regulators. Until the present, the influence of P27 protein and cyclin E on progression of colon cancer was unclear. The aim of this study was to observe the expression features of P27 protein and cyclin E in the tissues of colon neoplasms, and to investigate the relationship between colon neoplasms and tumor special growth factor (TSGF). METHODS: Sixty-nine cases of samples included 23 normal tissues, 28 colon polyps (13 inflammatory polyps and 15 adenomatous polyps), and 18 colon carcinomas. The location and expression of P27 protein and cyclin E were determined using immunohistochemical method in all samples. These samples were diagnosed using formal pathological techniques simultaneously; the relationship between colon neoplasms and TSGF was also investigated. RESULTS: The positive signal of P27 and cyclin E was found mainly in the cytoplasm and extracellular matrix of normal colon tissues, inflammatory polyps, and adenomatous polyps. Less amount of positive expression product of P27 protein and cyclin E was observed in colon carcinoma cells; and the positive signal was only located in the cytoplasm of gland-like cells. The content of TSGF in colon carcinoma tissues was significantly higher than that in normal tissues (117.3+/-57.02 versus 64.16+/-27.5,P< 0.01), but there was no significant difference between colon carcinoma tissues and inflammatory polyp tissues (117.3+/-57.02 versus 92.5+/-47.9,P >0.05). CONCLUSION: P27 protein and cyclin E participate in the adjustment process of colon neoplasm occurrence and progression. The reduced expression of P27 protein and cyclin E may indicate the possibility of colon carcinoma.

Adult↗
PubMed1984

Radiologic recognition of colonic diverticula simulating polyps.

The differentiation of colonic polyps and diverticula on the double-contrast barium enema is generally straightforward, using current diagnostic criteria. However, diverticula may be misinterpreted on the double-contrast barium enema as polyps when they appear uncommonly as filling defects within the barium pool. As a result of such erroneous interpretation, the patient may subsequently undergo costly and inconvenient repeat barium enema or colonoscopy. Carefully studied scout films, oblique views, compression spot images, and postevacuation films generally can differentiate these diverticula from polyps. The usual reason that a diverticulum assumes the appearance of a polyp is that it contains impacted stool.

Aged↗
PubMed1993

Turner's syndrome associated with sigmoid polyp and colon cancer: report of a case.

A 49-year-old woman with 45,XO karyotype Turner's syndrome and a recent onset of loose-to-watery stool passage was found to have a sigmoid polyp and adenocarcinoma in the ascending colon. Turner's syndrome is a result of a variety of abnormalities of the X chromosome. There are reports that the risk of malignancy, both gonadal and nongonadal in origin, is increased in patients with such chromosomal defects. Although, diet and heredity play important roles in the etiology of colorectal cancer, the relationship between cancer and certain congenital defects should be taken into account.

Adenocarcinoma↗
PubMed1998

Follow-up after transanal endoscopic microsurgery or transanal excision of large benign rectal polyps.

METHODS: Between January 1986 and December 1995, 238 patients with benign rectal polyps underwent either transanal endoscopic microsurgery (n = 226) or transanal excision (n = 12) at the Clinic of General and Abdominal Surgery, Johannes Gutenberg-University, Mainz. RESULTS: Mean polyp size was 4.2 cm; 89.1% of polyps measured more than 2 cm in diameter. In 89.1% of cases, histological analysis revealed polyps containing tubulovillous or villous adenomas. Synchronous colonic polyps were detected in 12.5% of patients. Follow-up data are available on 222 patients (94%). At follow-up examination, 169 of the 193 surviving patients (87.6%) were recurrence free. Seven of 193 patients (3.6%) had developed neoplastic colonic polyps and, in 17 patients (8.8%), metachronous polyps were detected. CONCLUSIONS: Transanal endoscopic microsurgical polypectomy was furthermore demonstrated to be a low-risk procedure with a low recurrence rate for the complete resection of large rectal polyps. At a follow-up rate of 61.1 %, the incidence of metachronous carcinoma ranged at 3.1%, which is markedly below the rate of 8-18% for tubulovillous or villous adenomas larger than 1 cm in diameter cited in the literature.

Adenoma, Villous↗
PubMed2002

Risk of renal and colonic neoplasms and spontaneous pneumothorax in the Birt-Hogg-Dubé syndrome.

The Birt-Hogg-Dubé syndrome, a genodermatosis characterized by benign tumors of the hair follicle, has been associated with renal and colonic neoplasms and spontaneous pneumothorax, but the risk of developing these disorders is unknown. We identified risk factors for renal tumors and spontaneous pneumothorax in 98 patients affected with the Birt-Hogg-Dubé syndrome, in 13 Birt-Hogg-Dubé haplotype carriers, and in 112 unaffected family members. Development of renal tumors was strongly associated with the Birt-Hogg-Dubé syndrome and age. The odds ratio for renal tumor in BHD-affected family members adjusted for age was 6.9 (95% confidence interval, 1.5-31.6) and approximately 9.0 for the other risk factors considered. Chromophobe renal carcinoma, an uncommon type of renal cancer, was the predominant type of renal cancer found. Spontaneous pneumothorax was also strongly associated with the Birt-Hogg-Dubé syndrome and age. The odds ratio for pneumothorax in BHD-affected individuals, adjusted for age, was 50.3 (95% confidence interval, 6.4-392), and about 32 times higher adjusting for the other risk variables. Colon cancer and colon polyps were not related to the Birt-Hogg-Dubé syndrome. The Birt-Hogg-Dubé syndrome confers an increased risk for the development of renal tumors and spontaneous pneumothorax. We found no increase in risk for the development of colon polyps or colon carcinomas.

Adult↗
PubMedDate not supplied

Computer-aided diagnosis scheme for detection of polyps at CT colonography.

Colon cancer is one of the leading causes of cancer deaths in the United States. However, most colon cancers can be prevented if precursor colonic polyps are detected and removed. An advanced computer-aided diagnosis (CAD) scheme was developed for the automated detection of polyps at computed tomographic (CT) colonography. A region encompassing the colonic wall is extracted from an isotropic volume data set obtained by interpolating CT colonographic scans along the axial direction. Polyp candidates are detected with computation of three-dimensional (3D) geometric features that characterize polyps, followed by extraction of polyps with hysteresis thresholding and fuzzy clustering using these geometric features. The number of false-positive findings is reduced by extracting 3D texture features from polyp candidates and applying quadratic discriminant analysis to the candidates. This CAD scheme was applied in 71 patients who underwent CT colonography, 14 of whom had colonoscopically confirmed polyps (n = 21). At by-patient analysis, sensitivity was 100%, with an average false-positive rate of 2.0 per patient. At by-polyp analysis, the scheme detected 90% of the polyps at the same false-positive rate. This CAD scheme permits accurate detection of suspicious lesions and thus has the potential to reduce radiologists' interpretation time and improve their diagnostic accuracy in the detection of polyps at CT colonography.

Adult↗
PubMed1989

The possible presence of a separate disease entity in nonfamilial polyposis of the large intestine.

Familial adenomatosis coli (FAC) traditionally has been diagnosed as the presence of more than 100 colonic adenomas, even if no familial occurrence is present. In the present communication, clinical features of FAC have been compared in detail to detect differences between familial and nonfamilial cases with regard to colonic and extracolonic lesions and to discover whether they constitute the same disease entities. No significant difference was found in the incidence of extracolonic lesions. The average number of colonic polyps in the nonfamilial cases of patients over 30 years old was 1128, the number of polyps was significantly higher in the familial cases (3154). When three patients with approximately 100 polyps were excluded, the mean number of colonic polyps in nonfamilial cases became 2608. This was similar to that of familial cases. Furthermore, the occurrence of approximately 100 polyps was extremely rare in familial patients who were over 30 years old. Therefore, most of the nonfamilial cases can be considered to be familial probands of FAC, but some, such as the three cases in the present study, may be a different disease entity, such as recessive adenomatous polyposis or multiple colonic adenomas.

Adenoma↗
PubMedDate not supplied

Analysis of air contrast barium enema, computed tomographic colonography, and colonoscopy: prospective comparison.

BACKGROUND: The usefulness of currently available colon imaging tests, including air contrast barium enema (ACBE), computed tomographic colonography (CTC), and colonoscopy, to detect colon polyps and cancers is uncertain. We aimed to assess the sensitivity of these three imaging tests. METHODS: Patients with faecal occult blood, haematochezia, iron-deficiency anaemia, or a family history of colon cancer underwent three separate colon-imaging studies--ACBE, followed 7-14 days later by CTC and colonoscopy on the same day. The primary outcome was detection of colonic polyps and cancers. Outcomes were assessed by building an aggregate view of the colon, taking into account results of all three tests. FINDINGS: 614 patients completed all three imaging tests. When analysed on a per-patient basis, for lesions 10 mm or larger in size (n=63), the sensitivity of ACBE was 48% (95% CI 35-61), CTC 59% (46-71, p=0.1083 for CTC vs ACBE), and colonoscopy 98% (91-100, p<0.0001 for colonoscopy vs CTC). For lesions 6-9 mm in size (n=116), sensitivity was 35% for ACBE (27-45), 51% for CTC (41-60, p=0.0080 for CTC vs ACBE), and 99% for colonoscopy (95-100, p<0.0001 for colonoscopy vs CTC). For lesions of 10 mm or larger in size, the specificity was greater for colonoscopy (0.996) than for either ACBE (0.90) or CTC (0.96) and declined for ACBE and CTC when smaller lesions were considered. INTERPRETATION: Colonoscopy was more sensitive than other tests, as currently undertaken, for detection of colonic polyps and cancers. These data have important implications for diagnostic use of colon imaging tests.

Barium Sulfate↗
PubMed2005

Altered gene expression in normal colonic mucosa of individuals with polyps of the colon.

PURPOSE: Expression levels of many genes are altered in colon cancer, relative to normal colonic mucosa. We recently reported that such differences also exist between grossly normal colonic mucosa of individuals with and without colon cancer, and between individuals with and without a family history of colon cancer. Here we report a study of individuals with no cancer but with polyps in the transverse, ascending/descending, or rectosigmoid colon. METHODS: Biopsies of grossly normal-appearing colonic mucosa from the rectosigmoid colon were taken from individuals with polyps, with or without personal/family history of colon cancer, and gene expression profiles compared with those from biopsies of control patients, with no polyps or known personal/family history. A global expression analysis was conducted of the same 15 genes used in our previous studies. RESULTS: We found significant differences in gene expression in normal-appearing rectosigmoid colonic mucosa between individuals with polyps and controls, regardless of whether personal or family history of cancer was present. CONCLUSIONS: Alterations in gene expression patterns in morphologically normal-appearing colonic mucosa are associated with the presence of adenomatous polyps. Prospective studies will be required to determine whether these alterations in gene expression can be used to predict risk of developing colon cancer.

Adult↗
PubMed1998

Validity of self-reported diagnoses leading to hospitalization: a comparison of self-reports with hospital records in a prospective study of American adults.

The authors compared interview reports with hospitalization records of participants in a nationally representative survey to determine the accuracy of self-reports of ischemic heart disease, stroke, gallbladder disease, ulcers, cataract, hip fracture, colon polyps, and cancers of the colon, breast, prostate, and lung. The study cohort consisted of 10,523 participants from the First National Health and Nutrition Examination Survey in 1971-1975 who were aged 25-74 years at the baseline examination and who completed a follow-up interview in 1982-1984. Self-reports of hospitalization for breast cancer were confirmed as accurate for 100% of cases where a hospital record was available. Self-report accuracy was also high for ischemic heart disease (84%), cataract (83%), and hip fracture (81%); it was moderate for lung cancer (78%), prostate cancer (75%), gallbladder disease (74%), colon cancer (71%), and stroke (67%); but it was low for ulcers (54%) and colon polyps (32%). Some of the self-reports of ulcers (20%), hip fracture (9%), ischemic heart disease (7%), and stroke (7%) were found to reflect diagnoses of other conditions of anatomic proximity. Accuracy of self-reports improved with higher levels of education, but was not generally related to age, gender, race, alcohol use, or smoking. The results suggest that self-reports of some diseases can be taken as accurate, but self-reports of other conditions might require medical record verification in epidemiologic follow-up studies.

Adult↗
PubMed1992

Reliability of in situ measurements of colorectal polyps.

A reliable and sensitive in situ method for measuring polyp size is fundamental for growth studies of colonic polyps. A measuring probe inserted through a colonoscope can give a visual assessment of polyp diameter, and from a picture of the polyp the area of the polyp on the picture can be calculated by computerized analysis. To test the reliability and sensitivity of these two in situ measurements, 43 colonic polyps (mean diameter, 8.5 mm; range, 4-20 mm) removed by snare diathermy resection were examined. The maximal diameter was measured, and two Polaroid pictures taken of each polyp. After polypectomy each polyp was subjected to extracorporeal reassessment of diameter and measurement of weight and volume. By computerized analysis of the pictures the following variables were estimated: 1) area of the polyp on the picture; 2) largest diameter; 3) maximum width 90 degrees on the largest diameter; 4) maximum distance from centre of gravity; and 5) minimum distance from centre of gravity. Results showed good correlation between diameter measured in situ and after removal (r = 0.93), diameter raised to the 3rd power and weight (r = 0.93), and also to volume (r = 0.77). Area analysis compared with weight was less good (r = 0.72). A very high correlation was demonstrated between weight and volume (r = 0.99). We conclude that the measurement of diameter in situ with a measuring probe is sensitive and somewhat more reliable than computerized analysis of size. The present 3-year follow-up and intervention study will show which of the two methods is preferable for evaluation of polyp growth.

Colonic Polyps↗
PubMed1990

Proliferation rate of colonic mucosa in normal subjects and patients with colonic neoplasms: a refined immunohistochemical method.

An increased colonic epithelial proliferation rate and an increase of the cryptal proliferative zone are probable markers of increased susceptibility to colonic cancer. In this study an immunohistochemical method using 5-bromo-deoxyuridine (BrdUrd) to measure the proliferation rate of colonic mucosa in vitro was used. Fresh endoscopic colonic biopsy specimens were incubated with BrdUrd and then processed for immunohistochemistry using a monoclonal antibody. Essential procedures with respect to the equal distribution of nuclei stained with BrdUrd in the biopsy specimens proved to be the cutting of the specimens before incubation and the use of a microwave oven at the beginning of incubation. The use of the procedure of the running average showed that 12 length cut crypts are sufficient to determine reliably the proliferation rate, expressed as the labelling index (LI). This was determined in the biopsy specimens of 10 subjects without organic colonic disease, eight patients with adenomatous colonic polyps, and in six patients with (recent) colonic carcinoma. Mean LI in the controls was significantly lower than in patients with colonic polyps and in those with colon cancer. It is concluded that this method is promising for screening persons at risk for colon cancer and will be of great potential in performing dietary intervention studies in these subjects.

Adolescent↗
PubMed2003

Criteria for the diagnosis of dysplasia by endoscopic optical coherence tomography.

BACKGROUND: Endoscopic optical coherence tomography provides images of the GI mucosa and submucosa in microscopic detail. It is unknown whether endoscopic optical coherence tomography can reliably detect dysplasia. Colon polyps were used as a model to determine whether dysplasia in GI tissue has characteristic optical coherence tomography imaging features. METHODS: Endoscopic optical coherence tomography images of colon polyps and normal colon tissue were obtained at colonoscopy. In real time, endoscopists compared tissue organization and light scattering for polyps and normal mucosa with endoscopic optical coherence tomography. Imaged polyps were removed and evaluated histopathologically. Organization and light scattering, as assessed by endoscopic optical coherence tomography at colonoscopy, were compared for adenomas versus hyperplastic polyps. A computer program also quantified and compared the degree of light scattering for hyperplastic polyps and adenomas. RESULTS: A total of 44 polyps were imaged in 24 patients (30 adenomas, 14 hyperplastic polyps). Endoscopic optical coherence tomography images of adenomas had significantly less structure (p = 0.0005) and scattered light to a lesser degree than hyperplastic polyps (p = 0.0007). Hyperplastic polyps were significantly closer in organization (p = 0.0003) and light scattering (p = 0.0006) to normal mucosa as compared with adenomas. By digital image analysis, the light-scattering property of hyperplastic polyps was closer to normal mucosa compared with adenomas (14.86 vs. 45.81; p = 0.0001). CONCLUSIONS: Real-time endoscopic optical coherence tomography imaging differentiated adenomas, hyperplastic polyps, and normal colon tissue. By using the colon adenoma as a model, the endoscopic optical coherence tomography characteristics of dysplasia are loss of tissue organization and reduced light scattering.

Adenoma↗
PubMed2005

Sporadic colonic hamartomas in adults: a retrospective study.

BACKGROUND: Colonic hamartomas are uncommon in adults. The aims of this study were to determine (1) the prevalence of colonic hamartomas in an adult population undergoing colonoscopy and (2) the clinical, endoscopic, and histologic features of colonic hamartomas in adult patients. METHODS: A pathology database identified 19 adult patients of 12,707 patients with colonic hamartomas in the 11-year study period from January 1992 to October 2002. An endoscopic computer database provided information about the number of colonoscopies performed and the presence or the absence of colonic polyp(s) in study patients. Charts of patients with colonic hamartomas were reviewed, and clinical and demographic data were collated. RESULTS: Nineteen patients were found to have colonic hamartomas. The mean age of these patients was 55 years, with an age distribution ranging from 25 to 81 years. The prevalence of colonic hamartomas in this study population was 0.15%. The prevalence of hamartomas in patients with colon polyps at index colonoscopy was 0.073%. Colonic hamartomas were more common in men than in women. The indication for colonoscopy for the majority (68%) of patients was hematochezia or the presence of occult blood in the stool. Three fourths of the polyps were greater than 1 cm in diameter, and 89% were pedunculated. Two thirds of the hamartomatous polyps were localized to the rectosigmoid region. Endoscopic characteristics of hamartomas were indistinguishable from adenomas. CONCLUSIONS: Colonic hamartomas in adults are rare. They tend to be single, pedunculated, and localized predominantly in the rectosigmoid region. Endoscopic resection of colonic hamartomas was successful in all patients.

Adult↗
PubMed1982

[The "false-positive polyp" during contrast examination of the colon (author's transl)].

44 cases of false-positive radiological diagnosis of colonic polyps are reviewed with regard to cause, frequency, distribution and radiological criteria. Most common causes are scybala and air bubbles (77%) and effects of overlapping and projection (19%). Due to extensive folding of the colon misinterpretations are frequently seen in the sigmoid and in the area of both flexures; the folding allows overlapping of mucosal structures and trapping of bowel contents. The validity of roentgen signs in polyp diagnosis and the limits of colonoscopy are discussed. Diagnostic reliability may be improved by optimal technique of examination and standardized proceeding.

Colonic Neoplasms↗