[Adenomatous polyps in colon and rectum after cholecystectomy]

The frequency of rectal and colonic polyps was compared in 33 patients with history of cholecystectomy and 37 patients without it. The data were evaluated retrospectively from our medical bank records. We found a major incidence of adenomatous polyps in the group of patients with cholecystectomy, the same in females as in males, with a female prevalence in 2.7:1 ratio in contrast with the group without surgery, where the ratio was 1.5:1 with a male prevalence. We didn't find any association between cholecystectomy and colorectal cancer. All the patients with adenocarcinoma were in the group without cholecystectomy.

Adenomas and hyperplastic polyps in screening studies

A survey is given of colorectal polyps detected in a prospective randomized screening study with the fecal occult blood test. It is demonstrated that colonoscopy in persons with positive Hemoccult-II tests results in detection of and removal of a higher number of adenomas than among controls. The strategy may, therefore, possibly be followed by a reduction of the incidence of colorectal cancer. Screen-detected adenomas were most often in males and were larger than among controls; they were most often in the sigmoid colon, whereas the rectum was the most frequent location for adenomas in controls. Eight percent of persons with screen-detected adenomas had some symptoms, which could be referred to adenomas, in contrast to 50% among controls. Hyperplastic polyps served as markers for adenomas in persons with positive Hemoccult-II as well as in controls with adenomas detected by colonoscopy; however, most persons with adenomas had no hyperplastic polyps. Endoscopic polypectomy did not result in any severe complications, but surgical removal in 2 of 22 patients proved fatal. The results presented are compared with those of other prospective randomized trials. The optimistic view--that the incidence of cancer may be reduced by polypectomy in persons with positive Hemoccult-II tests--stresses the importance of securing optimal colonoscopy service.

Evaluation and therapy of the patient with fecal occult blood loss: a decision analysis

We performed a decision analysis to evaluate cost per cancer detected, cost per neoplasm detected, and cost per treatable lesion of two common diagnostic strategies, barium enema-proctoscopy or colonoscopy as the first diagnostic test, for patients with fecal occult blood loss. The prevalence of polyps, cancer, and angiodysplasia, and the colonoscopy success rate were obtained from consecutive colonoscopy records. Costs were estimated from hospital charges; sensitivity and specificity of barium enema and colonoscopy were obtained from the literature. For treatable lesions (cancer, polyps, and angiodysplasia), the colonoscopy first strategy had a higher sensitivity (80% vs. 57%) and a higher specificity (95% vs. 80%) than the barium enema first strategy. Cost effectiveness measures were similar for the two strategies. Colonoscopy as the first diagnostic test had a lower cost per treatable lesion ($2,319 vs. $2,895) and a lower cost per neoplasm detected ($2,694 vs. $2,896), whereas the barium enema first strategy had a lower cost per cancer detected ($10,050 vs. $10,297). The lower cost per treatable lesion of the colonoscopy first strategy was not affected by changes in the prevalence of lesions, test characteristics, costs of tests, or colonoscopy success rate over clinically relevant ranges. The higher cost of colonoscopy was offset by its greater sensitivity and its capacity for biopsy and therapy. Therefore, since the cost per treatable lesion is lower and the sensitivity, specificity, and predictive value is superior, colonoscopy is recommended as the preferred initial test in evaluating a patient with fecal occult blood loss.

Natural history of colorectal polyps and the effect of polypectomy on occurrence of subsequent cancer

To elucidate the natural history of colorectal polyps and to observe the influence of endoscopic polypectomy on the incidence of colorectal cancer, we conducted a retrospective cohort study of all patients who had undergone colonoscopic examination at the Center for Adult Diseases, Osaka, between April 1974 and December 1985. The study subjects consisted of a control group (760 non-polyp patients) and a polyp group (648 polyp patients, including 136 treated by polypectomy at the initial examination). These subjects were followed up until the end of 1987 by record linkage with the Osaka Cancer Registry's file to observe the occurrence of colorectal cancer. The O/E (observed/expected numbers derived from the general population) was 5.1 (95% confidence interval = 2.5-9.4) and 1.0 (0.1-3.6) for the polyp and control group, respectively. When subjects in the polyp group were categorized into polypectomy and non-polypectomy sub-groups, the O/E was 2.3 (0.1-12.6) and 8.0 (3.4-15.8) respectively. The relative risk of undergoing polypectomy to developing subsequent cancer was estimated at 0.3 (0.1-2.1). These results suggest an increased risk of developing cancer among polyp patients and the possibility of prophylactic effect of polypectomy against subsequent cancer. A large-scale and long-term follow-up study is required to confirm these findings.

A prospective study of the prevalence of colonic neoplasms in asymptomatic patients with an age-related risk

This study was designed to determine the prevalence of colorectal neoplasia in healthy, asymptomatic adults with an age-related risk for colorectal neoplasia. Ninety patients were studied with air contrast barium enema and colonoscopy. The study population included 61 males and 21 females, with an age range of 51-82 yr (65 +/- 2 yr). Adenomatous polyps were found in 27% of males and 14% of females or 24% of patients overall. Sixty-six percent of these neoplasms were above the rectosigmoid junction and the mean size of the polyps was 6.5 +/- 1.2 mm. In two patients, carcinoma was discovered. A linear association between age and the prevalence of colonic neoplasia was not demonstrated. This study demonstrates a relatively high prevalence of colonic neoplasia in patients with an age-related risk.

Evidence for the existence of different types of large bowel tumor: suggestions from the clinical data of a population-based registry

The clinical findings of a population-based colorectal tumor registry have been analyzed to determine elements of supporting or not supporting the existence of different types of large bowel cancer. Age-specific incidence rate of the 409 registered patients rose sharply with increasing age in all segments of the large bowel; however, regarding left colon and rectum, the male: female ratio showed a marked male preponderance, more evident in the more advanced age groups. Histopathology, studied in 87% of patients, revealed adenocarcinoma as the most frequent feature; however, adenocarcinoma with concomitant adenoma (i.e., presumably arising in adenoma) was observed in 14.3% of cancers of the left colon, in 17.7% of rectal tumors, but in only 5.7% of neoplasms of the proximal colon (P less than 0.05 and P less than 0.01, respectively, vs. left colon and rectum). Some histological features (carcinoid and mucinous carcinoma) were observed in right-side tumors only. Analysis of the familial occurrence of cancer showed that a significantly larger proportion of patients with neoplasms located in proximal colonic segments had three or more first-degree relatives affected by (or deceased from) cancer of all sites. Similarly, colorectal tumors among relatives were more frequent in patients with right-side cancer. The location of the 793 polyps observed during 3 years of registration showed that more than 70% of adenomas were located beyond the splenic flexure, overlapping the distribution of cancers. In conclusion, the differences of sex ratio at different colonic subsites, the higher fraction of adenocarcinomas with adenomas in cancer of the more distal tracts of the large bowel, and the more marked familial occurrence of colorectal cancer in patients with right-side neoplasms tend to support the view that cancer of the proximal colon, cancer of the distal colon, and cancer of the rectum may actually be three different types of tumors.

Results of a repeat television-advertised mass screening program for colorectal cancer using fecal occult blood tests

The results of a 1987 television-advertised colorectal screening program using fecal occult blood tests (FOBT) are compared with the initial 1986 program (results in parentheses). In the 1987 program, 73,508 fecal occult blood test (FOBT) kits were distributed free of charge, of which 63% were returned for analysis (57,000, 53%). Twenty-five percent of persons from the initial screening participated again in the 1987 program: 1,303 or 2.8% of persons had a positive screen (1,165, 3.9%). The predictive value of a positive screen was 23% for an adenomatous polyp and 8% for colorectal cancer (22%, 8%). Seventy-nine percent of the cancers detected were Dukes A or B or carcinoma in situ (78%). In order to promote a more thorough diagnostic work-up in positive screenes, a suggested diagnostic algorithm for the work-up of a positive FOBT was sent to participating physicians. Despite this, 35% of positive screenees had a diagnostic work-up limited to a repeat FOBT, and/or sigmoidoscopy only (32%). In conclusion, television-advertised mass screening programs consistently enroll large numbers of participants. The rate of compliance (percent of kits returned) and the limited diagnostic evaluation of persons with a positive screen appear to be the major factors limiting the success of our screening program.

[Clinico-anatomical study of juvenile polyps in Asturias]

We have made a multifactorial study relating to the cases of juvenile polyps diagnosed in Asturias from 1977 to 1985. We have valued its histological nature and its evolutive behaviour especially as to what refers to the colonic carcinoma. We have analysed its localization and clinical features and noticed an improvement in diagnostic efficiency according to the broader and better use of endoscopy. We also show the need of a more interventionist attitude as regards to this pathology.

Polyps of the large intestine in Aarhus, Denmark. An autopsy study

In 336 consecutive autopsies a total of 305 tumors were recorded in the large intestine. Of these, 184 were adenomas occurring in 26% of the 196 men and 17% of the 140 women, resulting in an overall prevalence of 22%, or 15% when standardized to the world standard population (WSP). The prevalence of adenomas increased with age, and a shift from distal to proximal location occurred in the older age groups, mostly accounted for by the greater tendency to multiplicity in old age. Regardless of age 57% of the cases of adenomas could have been identified by flexible sigmoidoscopy. The prevalence of hyperplastic polyps was 13%, and an association between these and adenomas was found. Five adenocarcinomas occurred in the study. With some exceptions, which are discussed in detail, the results are in accordance with studies from other countries with a high incidence of colorectal cancer and similar socioeconomic composition. The study supports the theory of the adenoma-carcinoma sequence.

Management of invasive carcinoma in pedunculated colorectal polyps

Management of patients with endoscopically removed pedunculated colorectal polyps found to contain invasive carcinoma is controversial. When the endoscopist is confident that the polyp has been completely removed and the margins are pathologically clear, the salient issue which should guide subsequent management is the likelihood of lymph node metastases. Analysis of several institutional reviews has led the authors to conclude that the incidence of lymph node metastases is negligible in those patients in whom careful pathologic examination discloses free margins of resection, absence of lymphatic invasion, and well-differentiated or moderately well differentiated histology. Adhering to these criteria, pedunculated polyps containing invasive carcinoma can be safely managed by endoscopic polypectomy alone.

Colorectal polyps in the Upper Galilee

This study of colorectal polyps is based on 129 patients in whom 241 colorectal polyps were diagnosed and excised by colonoscopy in the Gastroenterology Unit of a hospital in the Upper Galilee, Israel, between 1 July 1984 and 30 June 1987. The male:female ratio was 2:1. Anemia was demonstrated in 7% and positive Hemoccult II test (Smith Kline, USA) in 64%. The types of polyp were 58% adenomatous, 25% hyperplastic and 15% inflammatory. Adenomatous polyps were larger than the other types (chi 2 = 13.24, P less than 0.01), and were more frequent in the left colon than inflammatory polyps (chi 2 = 4.67, P less than 0.05). The annual incidence of colorectal polyps and the percentage of colonoscopies that revealed polyps were highest for Jews of European/American origin (5.3/10,000, 26%) compared with Jews of Israeli and Asian/African origin and Arabs (2/10,000, 6%; 1.3/10,000, 12%; and 1/10,000, 9%, respectively). These data confirm findings of other investigators showing a higher incidence of colorectal polyps in European/American Jews than in other ethnic Israeli groups.

Small polyps found during fiberoptic sigmoidoscopy in asymptomatic patients

STUDY OBJECTIVE

To determine the prevalence of small polyps in the rectosigmoid in an asymptomatic group and the likelihood of finding synchronous neoplastic polyps proximally at colonoscopy.

DESIGN

Asymptomatic patients with polyps 9 mm or less found at screening fiberoptic sigmoidoscopy were referred for colonoscopy, at which time all polyps were removed.

SETTING

Screening fiberoptic sigmoidoscopy unit.

PATIENTS

Referral from Executive Health Wellness Clinic and large multispeciality clinic.

RESULTS

From 3923 sigmoidoscopic examinations, 258 asymptomatic subjects (7%) were identified who had polyps 9 mm or smaller. One hundred and eighty-nine patients (73%) had colonoscopy. In 179 patients, the target lesion noted at sigmoidoscopy was identified at colonoscopy. Based on histology of the target lesion, patients were divided into three groups: Group 1 (72 patients) had only hyperplastic polyps; Group 2 (69 patients) had at least one neoplastic polyp; and Group 3 (31 patients) had polyps with normal histology. Seven patients were not classified. Neoplastic polyps were found proximally in 21 patients in Group 1 (29%; 95% CI, 19 to 39), 23 patients in Group 2 (33%; 95% CI, 22 to 44), and 4 patients in Group 3 (13%; 95% CI, 4 to 30). There was no difference in mean age between groups. The results were similar when only polyps 5 mm or smaller were analyzed.

CONCLUSION

Because small polyps of any histologic type in the rectosigmoid indicate a high risk for having neoplastic polyps proximally, the guidelines of both the American College of Physicians and the American Society of Gastrointestinal Endoscopy may need to be revised. Colonoscopy seems justified in any patient in whom a small polyp is discovered at sigmoidoscopy.

Hemoccult screening for colorectal cancer

A community hemoccult screening project for colorectal cancer resulted in the processing of 18,198 specimens. Positive test results were reported in 3 percent of the total, which ultimately resulted in the identification of 20 colorectal malignancies (0.1 percent) and 53 benign polyps (0.3 percent). The number of malignancies and polyps identified was disappointingly low. Our findings would challenge the concept of unsupervised mass screening from the viewpoint of cost-effectiveness; however, because of the numerous voluntary services and supplies, this particular project was useful in educating the public about early colon cancer detection.

Results of a mass screening program for colorectal cancer

Following a series of educational newscasts about colorectal cancer that were aired on a local television news program, stool guaiac slide kits were distributed on request to 72,000 persons in Memphis. One or more slides were positive In 1310 (6%) of the 23,000 kits returned. Of the 1310 individuals with positive cultures, 597 (45%) saw a physician for further evaluation. Sixty-five of these persons received inadequate evaluations. Of the 532 individuals (90%) who received adequate evaluations, 154 (26%) had no evidence of pathology that would account for occult blood. Of the remaining 443 persons, 26 were found to have colorectal cancer, and 20 of these 26 persons were found to have surgically amenable lesions (Dukes' stages A through B2). In addition, 67 potentially precancerous polyps were found. Mass screening for colorectal cancer using guaiac slide tests, coupled with patient compliance for a screening protocol and adequate follow-up evaluation, has the potential to identify and treat early colorectal cancer.

Incidence and familial occurrence of colorectal cancer and polyps in a health-care district of northern Italy

The first year of registration of colorectal tumors in a predominantly urban population (263,546 inhabitants) of northern Italy gave us the opportunity to investigate: (a) the incidence (crude, age-specific, age-standardized) of both colorectal cancer and polyps and their localization; (b) the familial occurrence of these neoplasms; and (c) if the data could fit into the "Adenoma-Carcinoma Sequence." Crude incidence of cancer was 52.8 new cases/100,000 in 1984, with 53.4 cases in men and 52.2 cases in women. The corresponding figures for polyps were 59.6 new cases, with 83.4 in men and 37.3 cases in women. The incidence increased with age for both cancer and polyps, although the latter were more frequent until patients were in their sixties and the peak of incidence of polyps anticipated that of cancer by a 5 year period. Both cancer and polyps had a similar distribution in the large bowel, more than 60% being located in the left distal portion. There were 72 cases of colorectal cancer among the first-degree relatives of the registered patients compared with 16 in the controls (RR = 4.26, chi 2 = 27.2 p less than 0.001). An increased frequency of cases of colorectal cancer in the families was found in both the cancer group and the polyp group. In conclusion, the observed incidence of large bowel tumors was similar to that of other well-developed countries. The earlier rise and peak of age-specific incidence of polyps as compared to cancer, the similar distribution of benign and malignant neoplasms in the various intestinal tracts, and the similar familial aggregation observed both in the cancer and in the polyp groups further support the "polyp-cancer sequence" and provide us with a promising strategy for the prevention of colorectal malignancies.

[Rectocolonic polyps in Senegal. Results of 1500 lower endoscopies carried out at the Dakar General Hospital]

57 polyps were discovered during 1,500 low endoscopies, and 24 of them were adenoma. In the same period of time, 26 proctocolitic adenocarcinomas were found. Adenomatous polyps appear to be 5 times less frequent in Senegal than in industrialized countries and frequency of colitic cancer should be of the same frequency, that is far less negligible. Even if proctocolitic cancer does not set up any Public Health problems one could envisage systematic screening of polyadenoma in every patient aged more than 40. Proctosigmoid being the seat of most adenoma, fibrosigmoidoscopy appears well adapted to this kind of screening because it does not require any preparation, it is easy to perform and well accepted.

Adenomas, metaplastic polyps and other lesions of the large bowel: an autopsy survey

Out of 1,014 large intestines examined, adenomatous polyps were encountered in 170 (16.8%) and metaplastic polyps in 67 (6.6%). Both types of polyps were more prevalent among the Chinese than the Malays and Indians. The prevalence rates corresponded to the relative risks for large bowel cancer for the respective ethnic groups. This suggests that causative factors such as dietary influence which are common to adenomatous polyps and cancer of the large bowel are operating at different levels among the different ethnic groups in Singapore. There are however, several factors between adenomatous polyp and colorectal cancer which are not congruent suggesting that the relationship between these two lesions though close is not a simple or direct one. On the other hand, the present study has shown several similarities between the epidemiological characteristics of metaplastic polyps and cancer of the large bowel. It is speculated that the causative factor(s) for metaplastic polyps may occur in association with carcinogen of the large bowel, but has an independent action. Consequently, while the metaplastic polyp may not itself be regarded as a premalignant lesion, the possibility that it may be a marker for increased risk for colon cancer is not excluded. Ulcerative colitis is rare in Singapore, and is not considered an important lesion in the pathogenesis of large bowel cancer in this country.

Geographic differences in the prevalence and distribution of large-bowel polyps--colonoscopic findings

The large-bowel polyp pattern in two widely separated geographic regions of Sweden, Bollnäs in the central part and Trelleborg in the south, was studied prospectively by colonoscopic polypectomy. In Bollnäs 11.8% of 1,153 patients had neoplastic, and 3.8% hyperplastic, polyps. In Trelleborg 29% of 1,040 patients had neoplastic, and 17.3% hyperplastic, polyps. Furthermore, the Trelleborg patients had, on average, more polyps per patients than their Bollnäs counterparts: 2.0 versus 1.5 neoplastic, and 2.1 versus 1.7 hyperplastic, polyps. There was a marked difference in the anatomic location of the polyps between the two regions: in Trelleborg 55.4% of the neoplastic, and 40.5% of the hyperplastic polyps were distributed above the rectosigmoid, compared with 20.9% and 26.4%, respectively, in Bollnäs. The findings offer an explanation of the fact that the incidence of colorectal carcinoma in the Malmö region, close to the Trelleborg area, is the highest in Sweden.

Gastric and duodenal polyps in familial adenomatous polyposis: a prospective study of the nature and prevalence of upper gastrointestinal polyps

One hundred patients with familial adenomatous polyposis have prospectively undergone gastroduodenoscopy to identify and characterise polyps found. Forty six patients had polyps in the stomach or duodenum. Thirty five patients had adenomas (33 in duodenum, two in stomach) and 26 patients had fundic gland polyps. Some of these patients had polyps in the stomach and the duodenum. Adenomas in the duodenum were present in 33% of patients studied with Gardner's syndrome variant (p = 0.04). Adenomas were also more common in older patients. As adenomas may be a precursor of adenocarcinoma, routine surveillance of the stomach and duodenum with gastroduodenoscopy is recommended in patients affected with familial adenomatous polyposis.

Epidemiology of polyps in the rectum and colon. Recovery and evaluation of unresected polyps 2 years after detection

In an endoscopic population screening study for colorectal polyps among 200 men and 200 women, 50-59 years of age, 215 polyps less than 5 mm in diameter were left in situ for the present 2-year follow-up examination. The attendance rate was 102 of 106 (96%) for polyp patients and 77 of 90 (86%) in the control group. Of 194 polyps, 143 (74%) in the 102 polyp-bearing individuals were recovered for histological evaluation and 57 polyps were registered as new. Ninety-nine (50%) of the polyps were hyperplastic, 45 (23%) were adenomas, and 45 (23%) were mucosal tags. Both growth and regression of polyps were registered. Regression was commoner in the distal part of the rectum than in the proximal part or distal sigmoid colon. Growth was similar for recovered adenomas and hyperplastic polyps, whereas mucosal tags more often showed diminution in size. No polyp had reached a size of more than 5 mm in 2 years, and no case of severe dysplasia or carcinoma was registered. The estimated total polyp mass more than doubled both for adenomas and hyperplastic polyps. It is concluded that the time interval between initial examination with removal of polyps 5 mm or larger in diameter and the first follow-up examination may safely be set at 2 years.

Epidemiology of polyps in the rectum and sigmoid colon. Discriminant analysis for identification of individuals at risk of developing colorectal neoplasia

In an endoscopic population screening examination for detection of colorectal polyps among 324 men and women aged 50-59 years, adenomas greater than or equal to 5 mm in diameter were found in 38 individuals, and 212 were polyp-free. Dietary registration was performed by 155 individuals on a case/control basis. At 2 years' follow-up study polyps less than 5 mm in diameter were also removed. This rendered a total of 39 adenoma patients and 59 polyp-free individuals available for a combined analysis of both case history and dietary information. Application of a linear discriminant model on the combined clinical and dietary information enabled us to select a possible set of variables to characterize 88 out of 98 individuals (90%) correctly as adenoma patients or polyp-free individuals. However, when only case history information was used for the total material of 38 adenoma patients and 212 polyp-free individuals, only 189 out of 250 individuals (76%) were correctly classified. Although age, smoking habits, and a family history of colorectal cancer appeared as useful variables in the discriminant function, this study demonstrated the importance of nutritional factors in characterization of adenoma patients in the present age group of 50-59 years. In the present study we could not find any set of case history information which could indicate the usefulness of a questionnaire-based 'pre-screening' to guide recommendations for endoscopic screening examination.

Colorectal adenomatous polyps and carcinoma in Ashkenazi and non-Ashkenazi Jews in Israel

In Israel, the incidence of colorectal cancer among European-American-born Jews is approximately 2.5 times that of African-Asian-born Jews. To determine the risk of all colorectal tumors for the two ethnic groups, 335 patients with colorectal adenomatous polyps and 295 with colorectal cancer, diagnosed between 1980-1984 at the Sheba Medical Center, were compared to the 35,094 persons attending the outpatient clinics at the same hospital, during September and October 1984. Ashkenazi patients (European-American-born) had a 2.5-fold risk (95% confidence interval 1.9-3.3) of colorectal polyps compared to non-Ashkenazi patients (African-Asian-born). The risk was similar for males (odds ratios [OR] = 2.3) and females (OR = 2.8). Ashkenazis also had a significantly enhanced risk of carcinoma: OR = 3.1; 95% confidence interval 2.2-4.3. The risk ratio was slightly higher for males (OR = 3.5) than females (OR = 2.7). Age-specific analyses demonstrated an elevated risk of both malignant and benign neoplasms among Ashkenazi patients at all ages at diagnosis. Among the polyp patients, the highest risk ratio was for patients between 30 and 49 years old, while among the cancer patients the risk was highest in the group of 60-69-year-olds. The distribution by size of polyps, number of polyps, as well as polyp subsite, was similar for Ashkenazi and non-Ashkenazi patients; however non-Ashkenazis tended to have slightly more right-sided colon cancer.

[Colorectal polyps and cancers by sub-site: epidemiologic findings in Geneva and Vaud]

The present study is a comparative analysis of the adenomatous polyps and colorectal cancers, registered during a determined period within the population of the cantons of Geneva and Vaud. The analysis is particularly based on the polyp/cancer ratio by sub-site. Histological type as well as age and sex of the patient are taken into consideration.

Epidemiology of polyps in the rectum and sigmoid colon. Evaluation of breath methane and predisposition for colorectal neoplasia

The clinical significance of methanogenic bacteria in large-bowel carcinogenesis has not been established so far. As part of a screening study of a randomized population sample of 200 men and 200 women aged 50-59 years, the present breath methane study was designed to gain further information on methane excretion in relation to premalignant colorectal lesions, familial cancer disposition, and dietary fat and fiber. Testing for breath methane excretion did not contribute towards the identification of individuals with premalignant colorectal lesions and therefore should probably not be considered a screening tool.

The incidence and prevalence of familial polyposis coli in Denmark

Based on the Danish Polyposis Register, the frequency of familial polyposis coli was estimated at the end of 1982. The mean annual incidence rate of polyposis coli has remained rather constant at approximately 1 X 10(-6) X yr-1 since the forties. The life-time risk of developing polyposis coli is about 1 X 10(-4). The point prevalence rate was 26 X 10(-6) at the end of 1982. The number of cases found in sibs and children of probands made it probable that a nation-wide prophylactic examination of first degree relatives resulted in a complete identification of affected family members. The completeness of the Danish Polyposis Register in the period 1976-82 was estimated to be 90% and the validity of the diagnosis is considered to be 100%.

Epidemiology of polyps in the rectum and sigmoid colon. Evaluation of nutritional factors

Epidemiological studies have suggested an association between diet and colorectal cancer. Case/control studies, however, have been scarce, and studies based on interview with cancer patients who have symptoms from their cancer are inevitably prone to bias. An endoscopic population screening study for detection of colorectal adenomas enabled a double-blind registration of diet during 5 consecutive weekdays. Neither the participant nor the dietitian was informed of the findings at endoscopy. The estimation of 23 nutritional components was based on analysis of local commercial food and on the composition of foods in Norway. Results showed increasing consumption of fat and decreasing consumption of fiber and cruciferous vegetables in the presence of increasing neoplastic changes. The present material will form the basis for dietary-related follow-up studies.

Epidemiology of polyps in the rectum and sigmoid colon. Size, enzyme levels, DNA distributions, and nuclear diameter in polyps of the large intestine

Enzyme activity and cell cycle variables were measured in 38 adenomas and 9 hyperplastic large-intestinal polyps equal to or larger than 5 mm in diameter. The polyps were resected endoscopically from patients 50-59 years old. A significantly higher activity of lactate dehydrogenase (LD) was found in polyps from women than in those from men. A higher LD and activity was also observed in adenomas with moderate to severe dysplasia than in those with mild dysplasia. A significantly higher activity was found for LD and glucose-6-phosphate dehydrogenase (G6PD) in adenomas greater than or equal to 10 mm than in adenomas less than 10 mm in diameter. DNA flow cytometry showed that all hyperplastic polyps were diploid and that two of the adenomas had an aneuploid DNA stemline in addition to the diploid one. The S-phase fraction varied from 3.5% to 26.5% and the G2 fraction from 0.4% to 6.7%. Two overlapping populations were found, based on nuclear size measurements. Hyperplastic polyps had almost only small nuclei, whereas adenomas had both small and large nuclei in various ratios. No statistical correlations were found between the S-phase or G2-phase fractions and polyp size or the presence of dysplasia. The number of adenomas with aneuploidy was too small to disclose a relationship to polyp size or enzyme activity. The increased enzyme activity in larger polyps and in polyps from women may point to certain risk factors in these special groups. The results indicate a further need for studies of combination of markers for prognostic evaluation of large-intestinal adenomas.

Extracolonic polyps in familial polyposis coli and Gardner's syndrome

Endoscopy and biopsy of the upper gastrointestinal tract and terminal ileum were performed in 24 patients with familial polyposis or Gardner's syndrome in order to further define the incidence of extracolonic adenomatous polyps. Polyps, usually multiple and small in size, were detected in the gastric fundus (12.5 percent), antrum (29.1 percent), duodenum (66.6 percent), and terminal ileum (41.7 percent). Histology showed hyperplasia of the fundic glands and cystic dilatation in the polyps of gastric fundus, and adenomas in several cases of antral (three patients) or duodenal polyps (14 patients). Polyps of the terminal ileum were either adenomas (five patients) or lymphoid aggregates. Patients with stigmata of Gardner's syndrome, desmoids or mesenteric fibromatosis presented a major incidence of adenomas in the duodenum, but not in other parts of the digestive tract investigated. Subsequent checkup after an average of 33 months in ten patients revealed an increase of lesions only in the duodenum in two patients. These findings confirm that adenomatous polyps are not limited to the colon and rectum, as previously believed, but can affect the whole gastrointestinal tract. Periodic surveillance of mucosa seems to be indicated, especially for the duodenum, since degeneration of adenomas into carcinoma is possible.

Prevalence of polyps in an autopsy series from areas with varying incidence of large-bowel cancer

The results of this multicentre autopsy study emphasize the relationship between the prevalence of adenomas and the incidence of large-bowel cancer. The highest proportion of autopsies with adenomas was observed in the area with the highest incidence of large-bowel cancer. The segmental distribution of adenomas within the colon was found to be similar to the site distribution of cancer. However, the lowest proportion of adenomas was found in the rectum, the segment in which cancer is most frequent. The latter finding suggests that either the adenoma-carcinoma sequence is a less important pathway in the pathogenesis of rectal cancer, or that more rectal than colonic adenomas become malignant. The high proportion of hyperplastic polyps in the rectum, and statistically significant regional differences following the same patterns as the incidence of rectal cancer suggest that there could be at least an indirect relationship between hyperplastic polyps and cancer of the rectum. Adenomas of both colon and rectum were more frequent in men than in women, contrary to findings with colon cancer. However, as for colon cancer, the sex ratio of adenomas changed with age, from slightly below unity in persons under 65, to above unity for those aged 65 and over. A major difficulty that emerged was the histological identification of "polyps" because of the degree of autolysis of epithelial cells in the mucous membrane, and this difficulty largely contributed to the poor consistency of histological reporting. Regular consistency surveys of histological preparations should be recommended in any type of multicentre study in which histological examination is included.

Epidemiology of polyps in the rectum and sigmoid colon. Histological examination of resected polyps

In an endoscopic screening study of rectosigmoidal polyps in a defined normal population aged 50-59 years, polyps 5 mm or larger in diameter were removed by diathermic snare resection for histological examination. Histological examination was possible in 50 of 55 polyps removed during colonoscopy from 27 men and 17 women. Of these polyps 41 (82%) were adenomas--12 with moderate dysplasia, 1 with severe dysplasia, and 2 with intramucosal carcinoma. In addition, a small ulcerating carcinoma, Dukes stage A, was found. A greater extent of dysplasia was found in rectosigmoidal adenomas in women, whereas more polyps were found in both distal and proximal parts of the colon among men. The size of adenomas and degree of dysplasia were unrelated to color of the lesions.

Fecal bile acid profiles of Japanese patients with adenomatous polyps of the large bowel: special reference to distribution, multiplicity, size and degree of dysplasia of the polyps

Bile acids have been implicated in carcinogenesis of the large bowel, and since epidemiological, clinical and histopathological studies suggest a link between adenomatous polyps and cancer of the large bowel, fecal bile acid profiles were studied in 33 patients with adenomatous polyps of the large bowel and these data were analyzed with particular reference to the distribution, multiplicity, size and degree of dysplasia of the polyps. The more polyps and the greater the severity of dysplasia, the higher was the excretion of total bile acids (mean mumol/day: single vs multiple polyps, 344.8 vs 369.1; mild vs moderate vs severe dysplasia, 347.5 vs 370.0 vs 399.3). However, in patients with larger polyps, total fecal bile acid excretion tended to be lower (mean mumol/day: large vs small polyps, 267.7 vs 389.5). These differences were not statistically significant. When fecal bile acid profiles were analyzed with respect to the extent of bacterial metabolism determined from the degree of dehydroxylation and oxidoreduction, there was a large variation with no consistency in relation to the factors studied among the polyp patients. Deconjugation of bile acids in feces was almost complete without difference among the patients. These results seem to indicate that the significance of bile acid in the development of adenomatous polyps in Japanese subjects is likely to be small.

Incidence of synchronous and metachronous colorectal carcinoma

Two hundred and twenty-three patients with colorectal carcinoma were treated consecutively at the University Hospital of South Manchester from May 1976 to January 1981. Twenty-four patients (10.7 per cent) were found to have more than one colorectal carcinoma. In 18 patients this was recognized either immediately or within 6 months of the initial diagnosis--synchronous carcinoma. In the other six cases a second carcinoma was found at a later time--metachronous carcinoma. The incidence of synchronous, and consequently the combined incidence of synchronous and metachronous carcinoma, was higher than previously documented. The anatomical distribution of the multiple carcinomas and the sex incidence in these patients was similar to that seen in patients with a single carcinoma of the large bowel. A high association of adenomatous polypi with multiple large bowel carcinomas was observed. The possibility of more extensive colonic resection in the younger patient with a favourable carcinoma is discussed.

[Gastric mucosal polyps--an irrelevant finding? Studies on the incidence and clinical significance]

Among about 20.000 patients who had a gastroscopy in a period of 6 years, 92 had gastric mucosal polyposis, diagnosed by endoscopy and histology, an incidence of 0.46%. Eight patients with an age average of 38 years had familial gastrointestinal adenomatosis, in six of them the criteria of Gardner's disease were fulfilled. The remaining 84 patients had an average age of 62 years. In patients with more than ten polyps the sex ratio (female to male) was 3.9:1. In 56 patients without familial gastrointestinal adenomatosis, coloscopy and(or) proctosigmoidoscopy was performed. In 18 there were polyps in the colon, in three an invasive carcinoma in an adenoma. In three further patients extensive carcinoma of the colon (in two with stenosis) was found. These observations suggest that patients with gastric mucosal polyposis have a higher incidence of colon polyps and carcinoma.

Colonoscopy in asymptomatic individuals with a family history of colorectal cancer

A prevalence screening program with colonoscopy was undertaken in four kindreds manifesting the cancer family syndrome. Forty-five percent of counseled patients underwent colonoscopy, providing 42 asymptomatic individuals. Seven patients (17%) were found to have adenomatous or villous polyps; two of these were malignant and one showed epithelial atypia. Three of the seven patients with polyps had multiple lesions. Only two patients had rectosigmoid polyps. From these limited data, colonoscopy is recommended as a useful screening procedure in individuals at high risk for colorectal cancer.

Spontaneous polyposis in the small intestine of germ-free and conventionalized BALB/c mice

The spontaneous polyposis in the small intestine of germfree (Gf) and conventionalized (Cv) BALB/c mice was studied. Gf mice were bred in our laboratory and maintained Gf in vinyl isolators. The first generation offspring of the Cv mice derived from the Gf mice was used as Cv animals. When they were 12 months old, the animals were killed under CO2 inhalation and autopsied carefully for the number and size of polyps with the aid of a dissecting microscope. The incidence of polyposis was higher in the Gf mice (68% in female and 89% in male) than in the Cv mice (37% in female and 51% in male). The number of polyps/mouse was also higher in the Gf mice (2.3 in female and 5.7 in male) than in the Cv mice (0.8 in female and 1.3 in male). All of the polyps were histopathologically adenomatous and developed only in the upper part (mainly duodenum) of the small intestine. The present study demonstrated that development of polyposis in the small intestine of BALB/c mice was suppressed by the presence of intestinal microflora.

Colorectal juvenile polyps: an epidemiological and histopathological study of 144 cases in Jordanians

The minimal incidence rate of colorectal juvenile polyps in Jordanians was 1.4 per 100 000 in the general population and 2.8 per 100 000 in children under 10 years of age. Out of 144 cases, nine had two to seven polyps and one juvenile polyposis coli. There was male preponderance and a mean age of 8 years: 96.5% of the polyps were in the rectum. Characteristically, stromal oedema, inflammation, ulceration with granulation tissue cap formation and gland regeneration were present. Epithelial hyperplasia was not uncommon and focal dysplastic change was occasionally noted, being always accompanied by hyperplastic change. Focal severe dysplasia was seen in one solitary juvenile polyp. It is concluded that varying degrees of focal epithelial atypia can occasionally develop in solitary juvenile polyps, rarely reaching severe dysplastic change. Malignant transformation in the commonly seen form of juvenile polyp (solitary type) is probably a rare phenomenon, but its frequency needs further evaluation.

[Duodenal polyps. Incidence, histologic substrate and significance]

378 duodenal polyps were identified by endoscopic biopsy since 1973 in the course of more than 25,000 oesophago-gastro-duodenoscopies, corresponding to an incidence rate of 1.5%. Heterotopias of the gastric mucosa and so-called inflammatory polyps were most frequent (35.7% and 35.2%, respectively), followed by hyperplasia of Brunner's glands (6.9%), lipid islets (2.9%) and lymphatic hyperplasia (1.8%). Histologically there was no correlate to the endoscopic findings. Hence, non-neoplastic polyps account for about 90% of duodenal polyps; they are harmless and generally produce no (or only minor) signs or symptoms. Clinically relevant polyps besides the primary and secondary malignant processes are the adenomas of the colon type (6.9%) and Peutz-Jeghers polyps (1.3%). Since these two may occur in gastrointestinal polyposis, "top-and-tail endoscopy" must be performed. The rate of complications of 15% in endoscopic loopectomy in the duodenum is clearly higher than that in the stomach and colon.

Fundic gland polyposis in patients without familial adenomatosis coli: its incidence and clinical features

Thirty-five cases of fundic gland polyposis detected by roentgenographic examination, gastrofiberscopy, and endoscopic biopsy were divided into two groups. The first group consisted of 23 cases without familial adenomatosis coli and is termed the nonadenomatosis coli group; the second group contained 12 cases with familial adenomatosis coli and is termed the familial adenomatosis coli group. Incidence of fundic gland polyposis was only 0.085% (23 of 27,000 cases) in the non-adenomatosis coli group but 38.7% (12 of 31 cases) in the familial adenomatosis coli group. In both groups, fundic gland polyps were multiple, small (less than 8 mm in diameter), and located in the body and fundus of the stomach. A solitary or large polyp was occasionally observed in the non-adenomatosis coli group. Histologic examination revealed simple hyperplasia of the fundic glands and microcysts in both groups. The age range was 51.6 +/- 12.3 yr (mean +/- SD) in the non-adenomatosis coli group and 25.3 +/- 8.6 yr in the familial adenomatosis coli group. The ratio of males to females was 5:18 in the non-adenomatosis coli group, and 7:5 in the familial adenomatosis coli group. The number of fundic gland polyps was smaller in the non-adenomatosis coli group than in the familial adenomatosis coli group. Our observations suggest that this lesion frequently coexists with familial adenomatosis coli, but that it is not specific to this disease.

Flexible sigmoidoscopy: diagnostic yield in 1015 patients

The purposes of our study were to 1) identify the number of neoplastic lesions (adenomatous polyps and cancer) diagnosable by flexible sigmoidoscopy (FS) in patients with symptoms of colorectal disease and 2) determine the age distribution of patients in whom neoplastic lesions are detected by FS. A total of 1015 patients, ages 20-89 years, underwent FS because of the following indications: rectal bleeding, occult blood loss, anemia, change in bowel habit, weight loss, and abdominal pain. FS examined a mean distance of 49 +/- 2 cm (SEM) in an average time of 11.5 min. A bowel preparation of 2 Fleet enemas was adequate in 95% of patients and the examination was well tolerated by all age groups. There were no complications encountered. Eight-five neoplastic lesions were identified in 78 patients. Fifty-four percent of all adenomatous polyps and 61% of the cancers were detected beyond 20 cm. Neoplastic lesions were identified in all adult decades studied, ranging from 3.2% of patients aged 20-40 years, 8.0% for patients between 40 and 60, and 10.1% from 60 to 80; with a peak yield of 11.2% in the 7th decade. Cancer was diagnosed only in patients more than 40 years; 3.3% of patients over 60 had carcinoma compared to 0.8% in patients less than 60. These data provide evidence for the value of FS as a safe initial diagnostic procedure to detect neoplastic lesions in symptomatic patients of all adult age groups.