Biopsy of colorectal polyps is not adequate for grading of neoplasia

BACKGROUND AND STUDY AIM

Valid tissue sampling of colorectal adenomas is crucial for their management in terms of treatment and follow-up. The aim of this study was to assess the validity of a cold biopsy sample as representative for the whole polypectomy specimen, with regard to histopathological features.

PATIENTS AND METHODS

As part of the Norwegian Colorectal Cancer Prevention trial, 442 participants (60% men) who fulfilled the criterion of colonoscopic recovery of adenoma that had been biopsied at flexible sigmoidoscopy, had their adenomas subsequently removed by polypectomy (snare resection) at colonoscopy. Logistic regression analysis was used to determine which variables contributed to the histopathological discrepancy between cold biopsy and polypectomy specimens.

RESULTS

Among the 532 colorectal adenomas biopsied at flexible sigmoidoscopy and removed by colonoscopy, the assessment of intraepithelial neoplasia (dysplasia) status was changed in 51 adenomas (10%), and 38 (7%) of them had been underestimated at biopsy compared with polypectomy. Likewise, the assessment of villousness was changed in 45 adenomas (9%), being upgraded in 26 (6%) at polypectomy compared with biopsy. In a multivariate model, the diameter of neoplasia at polypectomy was positively associated with increased risk of the underestimation of intraepithelial neoplasia and/or villousness influencing a diagnosis of advanced colorectal neoplasia, when cold biopsy and polypectomy specimens were compared ( Ptrend=0.01). Among 56 cases of advanced neoplasia, 35 (63%) showed only low-grade intraepithelial neoplasia on biopsy.

CONCLUSIONS

Biopsy-based diagnosis underestimated histopathological diagnosis in about 10% of colorectal adenomas detected by flexible sigmoidoscopy screening, but advanced neoplasia was underestimated in more than 60%. Efforts must be made to obtain polypectomy specimens to secure precise diagnosis.

Lifestyle-related risk factors and chemoprevention for colorectal neoplasia: experience from the large-scale NORCCAP screening trial

The objective of this study was to evaluate the potential beneficial effects of non-steroidal anti-inflammatory drugs (NSAIDs) and/or acetylsalicylic acid (ASA) and hormone replacement therapy (HRT) on colorectal neoplasia, and to compare their effects with those of lifestyle-related risk factors in 12 960 individuals who underwent flexible sigmoidoscopy screening examination. The association between these factors and colonic neoplasia was assessed by logistic regression analysis. NSAIDs and/or ASA intake were associated with decreased risk of distal low grade adenoma (DLGA) (adjusted odds ratio (OR) 0.80, P trend=0.02) in men. The duration of HRT was inversely related to the risk of DLGA (OR 0.89, P trend=0.08). Current smoking increased the risk of DLGA and distal advanced neoplasia (DAN) in both men (OR 2.50, P<0.01) and women (OR 2.30, P<0.01). There was a significant positive trend for increasing risk of DLGA (OR 1.16, P<0.01) and DAN (OR 1.20, P=0.02) with increasing use of alcohol among men, but not among women. Prescription of NSAIDs and/or ASA for chronic conditions may not be expected to have a substantial preventive effect on colorectal neoplasia in comparison with the adverse effect of smoking and alcohol. This may be explained by an increased risk of colorectal neoplasia for patients with conditions for which NSAIDs or ASA are being prescribed.

Inter-endoscopist variation in polyp and neoplasia pick-up rates in flexible sigmoidoscopy screening for colorectal cancer

BACKGROUND

The Norwegian Colorectal Cancer Prevention study is an ongoing flexible sigmoidoscopy (FS) screening trial for colorectal cancer. Twenty-one thousand average-risk individuals, aged 50-64 years, living in two separate areas in Norway were randomly drawn from the Population Registry and invited to once-only screening flexible sigmoidoscopy. Examinations were performed over 3 years, at 2 centres, by 8 different endoscopists, using the same type of equipment. The aim of the present study was to investigate possible differences between endoscopists in detecting individuals with polyps, adenomas and advanced lesions (adenomas with severe dysplasia and/or villous components and/or size larger than 9 mm and carcinoma) in flexible sigmoidoscopy screening.

METHODS

The present trial comprises data from 8822 individuals, aged 55-64 years, who have undergone a flexible sigmoidoscopy. In the study period, all lesions detected by the different endoscopists were registered. Tissue samples were taken from all lesions detected.

RESULTS

Detection rates varied significantly between endoscopists, ranging from 36.4% to 65.5% for individuals with any polyp, from 12.7% to 21.2% for any adenoma and from 2.9% to 5.0% for advanced lesions. In a multiple logistic regression model, the performing endoscopist was a strong independent predictor for detection of individuals with polyps (P < 0.001 ), adenomas (P < 0.001) and advanced lesions (P = 0.01).

CONCLUSION

Detection rates for colorectal lesions vary significantly between endoscopists in colorectal cancer screening. Establishing systems for monitoring performance in screening programmes is important. Supervised training and re-certification for endoscopists with poor performance should be considered.

The Norwegian Colorectal Cancer Prevention (NORCCAP) screening study: baseline findings and implementations for clinical work-up in age groups 50-64 years

BACKGROUND

Randomized controlled trials of sufficient power testing the long-term effect of screening for colorectal neoplasia only exist for faecal occult blood testing (FOBT). There is indirect evidence that flexible sigmoidoscopy (FS) may have a greater yield. The aim of this study was to determine the diagnostic yield of screening with FS or a combination of FS and FOBT in an average-risk population in an urban and combined urban and rural population in Norway.

METHODS

20,780 men and women (1:1), aged 50-64 years, were invited for once-only screening (FS only or a combination of FS and FOBT (1:1)) by randomization from the population registry. A positive FS was defined as a finding of any neoplasia or any polyp > or = 10 mm. A positive FS or FOBT qualified for colonoscopy.

RESULTS

Overall attendance was 65%. Forty-one (0.3%) cases of CRC were detected. Any adenoma was found in 2208 (17%) participants and 545 (4.2%) had high-risk adenomas. There was no difference in diagnostic yield between the FS and the FS and FOBT group regarding CRC or high-risk adenoma. Work-up load comprised 2821 colonoscopies in 2524 (20%) screenees and 10% of screenees were recommended later colonoscopy surveillance. There were no severe complications at FS, but six perforations after therapeutic colonoscopy (1:336).

CONCLUSIONS

The present study bodes well for future management of a national screening programme, provided that follow-up results reflect adequate proof of a net benefit. It is highly questionable whether the addition of once-only FOBT to FS will contribute to this effect.

Does a family history of cancer increase the risk of occurrence, growth, and recurrence of colorectal adenomas?

BACKGROUND

Familial history of colorectal cancer (FHCRC) is a recognised risk factor for sporadic CRC. The relationship to the growth rate of adenomas is largely unknown. Lifestyle related factors, which may also cluster in families, are also recognised risk factors for adenomas and CRC.

AIMS

To study the relationships between FHCRC and family history of other cancers (FHOC) among first degree relatives in relation to occurrence, growth, and recurrence of adenomas.

PATIENTS AND METHODS

Eighty seven patients with adenomas, participating in a double blind, three year, placebo controlled, endoscopic follow up and intervention study of growth and recurrence of polyps (50% men, 50-76 years). Polyps >9 mm were removed whereas the remainder and newly discovered polyps <10 mm were left in situ for three years before removal and histological diagnosis. Data were collected by means of dietary records, interviews, and questionnaires.

RESULTS

The adenoma cases with FHCRC had a fourfold higher risk of adenoma growth. In contrast, no significant association was found for adenoma recurrence. FHOC was not significantly related to increased risk of growth or recurrence. Family history showed no significant association with the risk of baseline adenoma occurrence. Adjustment for CRC risk factors, also known to cluster in families, did not alter the results.

CONCLUSIONS

FHCRC seems to be a strong risk factor for adenoma growth, but not for the earlier phases of CRC development such as the initiation of adenomas.

Genetic and protein markers related to in situ growth and multiplicity in small sporadic colorectal adenomas

BACKGROUND

Some early genetic events in the development of colorectal adenomas are known, but their relationship to in vivo growth characteristics is uncertain. This study compared in situ size changes and other clinicopathological variables with selected genetic and protein markers.

METHODS

56 adenomas (< or = 10 mm) from 39 patients were analysed for APC, CTNNB1 and K-ras mutations, allelic imbalance on 1p and 18q, microsatellite instability and immunohistochemical expression of HLA-DR, BAX, BCL-2 and Ki-67. For 42 of the adenomas, in situ growth was measured over 3 years. The total number of polyps in each patient was recorded.

RESULTS

K-ras was mutated in 8/56 adenomas. None of the regressing adenomas revealed such mutations, compared to 20% in those that maintained or increased their size. Multivariate linear regression analysis showed that tumour growth was higher in females compared to males, and was even higher in the presence of a K-ras mutation. APC mutations were found in 37/56 adenomas. CTNNB1 mutations were found in 2/19 adenomas without APC mutation. Deletions of 1p were found in 12/56 adenomas and, seemingly, most frequent in patients with few tumours. The most frequently expressed protein was BAX (33/41), but neither this nor the other proteins showed associations with an in situ growth pattern.

CONCLUSION

The multivariate linear regression model showed that patient gender and the presence of K-ras mutation had significant effects on tumour growth. The lack of the proliferative stimulus resulting from a K-ras mutation may contribute to the process of adenoma regression.

Grading of distal colorectal adenomas as predictors for proximal colonic neoplasia and choice of endoscope in population screening: experience from the Norwegian Colorectal Cancer Prevention study (NORCCAP)

BACKGROUND AND AIMS

The purpose of this study was to evaluate the utility of easily measured clinical variables at flexible sigmoidoscopy (FS) screening that might predict a proximal advanced neoplasm (PAN).

METHODS

We studied 1833 subjects with biopsy verified adenomas at FS who subsequently underwent full colonoscopy.

RESULTS

A total of 387 (21%) subjects had proximal colonic neoplasms (PCN) and 85 (5%) had PAN. In univariate comparison, the risk of PAN increased more than threefold in the presence of a distal adenoma measuring either > or =10 mm in diameter or containing villous components. Multiplicity of distal adenomas, severe dysplasia, or age > or =60 years increased the risk of PAN more than twofold. In the multivariate model, the presence of a distal adenoma > or =10 mm, villousness, and multiplicity maintained their significance as predictive variables for increased risk of proximal neoplasms, whereas sex and severe dysplasia lost their significance. By recommending colonoscopy only to individuals with multiple (>1) adenomas or any high risk adenoma at FS, we would have reduced the number of colonoscopies by 1209 (66%) but would have missed 32 (38%) participants with PAN and 217 (56%) with PCN. By using a 60 cm endoscope instead of an ordinary colonoscope at FS, nine (2%) participants with advanced neoplasms, including three patients with cancer, would have been missed.

CONCLUSION

The present study supports the concept of defining "any adenoma" as a positive FS, qualifying for colonoscopy. We recommend the use of an ordinary colonoscope instead of a 60 cm sigmoidoscope for FS screening examinations.

Continuous evaluation of patient satisfaction in endoscopy centres

BACKGROUND

A randomized sample of 14,000 men and women, aged 55-64 years, resident in the City of Oslo and Telemark County, were drawn from the population registry to be offered a flexible sigmoidoscopy (FS) screening examination. A questionnaire was designed to modify routines and evaluate patient satisfaction.

METHODS

Consecutive participants (4956) were given a questionnaire immediately after the FS to be filled in and returned by mail on the following day. Participants were asked questions about service, practical issues, and the level of pain during the FS and post-examination discomfort. They were also encouraged to give their comments in free text.

RESULTS

Questionnaire replies were received from 4574 (92%) out of 4956 participants. The vast majority reported to have experienced no (70%) or slight (21%) pain during the examination. Women reported pain and post-examination discomfort more often than men. Pain was also associated with age of the patient and length of bowel examined, but not with total examination time. The proportion of painless examinations varied between endoscopists from 62% to 81%. For all endoscopists collectively, this improved during the study period, irrespective of past experience, but trainees seemed to adopt the score of their masters.

CONCLUSIONS

The study demonstrated that the use of feedback information in an endoscopy screening unit may be useful in improving standards, including the performance of endoscopists. It is possible that the introduction of similar feedback systems in routine endoscopy laboratories may in the long run improve the reputation of gastrointestinal endoscopy.

Lifestyle-related factors and colorectal polyps: preliminary results from a Norwegian follow-up and intervention study

Lifestyle-related variables are suggested to play a major role in the development of colorectal cancer (CRC). Within a 3-year follow-up and intervention study with calcium and antioxidants against growth and recurrence of colorectal polyps, supplementary studies were performed in which different aspects of lifestyle were examined. Instead of polypectomy at diagnosis, polyps <9 mm were left in situ in 116 polyp patients (50-76 years, 50% men). After 3 years, all polyps were removed and subjected to histology. Two different sets of control groups were included (all controls were age- and sex-matched and proven to be free of polyps). We applied two different methods in order to assess most exposure variables. Generally, in case-control studies, the validity of the study outcomes is high if they are similar regardless of choice of controls and methods, since bias due to these choices may affect the risk estimates. In contrast, the validity of the study outcomes is low if dependent upon these choices. Our preliminary data support the theory that different factors may be of importance in different stages of the neoplastive formation, and that lifestyle-related factors are likely to play a major role in CRC development.

Screening of first degree relatives of patients operated for colorectal cancer: evaluation of fecal calprotectin vs. hemoccult II

Fecal calprotectin (CPT) is elevated in the majority of patients with known colorectal cancer (CRC), but the specificity is not clarified.

AIM

To evaluate if a CPT test (PhiCal ELISA) was more sensitive than Hemoccult II test in detecting colorectal neoplasia, and to obtain reference values in subjects with normal colonoscopy. To evaluate a possible relation between number and extent of dysplasia of adenomas in first degree relatives of patients with CRC and the stage of the carcinoma in the index casus. Further to study the prevalence of CRC and adenomas in the first degree relatives of patients operated for CRC.

METHOD

In a multicenter study, 253 first degree relatives of patients with CRC, aged 50-75 years (mean age 60 years) underwent colonoscopy after having delivered stool samples and three Hemoccult II slides.

RESULTS

In 237 first degree relatives from 148 patients with CRC, polyps were found in 118 (50%). Seventy three (31%) had adenomas and 17 had adenomas > or =10 mm. Five had asymptomatic cancers. The specificity of fecal CPT for adenomas at cut off levels <or =10, < or =15 and < or =20 mg/l were 47.4, 59.6 and 71.1%, respectively (max of three samples). The sensitivity at same cut off levels was 56.2, 45.2 and 31.5% and 4/5 of patients with carcinoma had CPT values >15 mg/l. The sensitivity of Hemoccult II for adenomas was 8%, and 4/5 of patients with carcinoma had negative Hemoccult II. The specificity for adenomas was 95%.

CONCLUSION

Fecal CPT test was more sensitive than Hemoccult II in detecting colorectal neoplasia but the specificity was lower. In a high risk group like first degree relatives of patients with CRC, there are good reasons to consider fecal CPT as a first test in selecting patients for endoscopy.

Does intake of alcohol increase the risk of presence and growth of colorectal adenomas followed-up in situ for three years?

BACKGROUND

Alcohol has been suggested as a promoter in the development of colorectal cancer (CRC). Our aim was to examine if alcohol intake was related to the presence and growth of colorectal adenomas <9 mm followed up in situ for 3 years.

METHODS

We compared 87 adenoma cases to 35 'hospital' and 35 healthy controls (age- and sex-matched and proven to be polyp-free). These cases were participating in a 3-year intervention study against growth and recurrence of polyps. Alcohol data were obtained using a structured interview (I) and a 5-day dietary record by weighing (DR).

RESULTS

The median intakes of alcohol were 5 g/day (I) and 6 g/day (DR). Increasing differences were found between I and DR with increasing alcohol intake. Increasing total alcohol intake showed a tendency to an inverse association with adenoma occurrence (ORs <0.5), in contrast to the tendency of a positive association with adenoma growth (ORs >5.8). No significant beverage-specific effects were observed at this low alcohol intake level. Those with an intake of >20 g alcohol/day (18%) had several indicators of an 'unhealthy' lifestyle that may also be independently associated with adenomas, and even CRC.

CONCLUSION

A very low intake of alcohol (<5 g/day) did not increase the risk of presence and of growth of adenomas followed-up in situ for 3 years, but we cannot exclude that an increased intake may increase the risk of adenoma growth.

Current diet and colorectal adenomas: a case-control study including different sets of traditionally chosen control groups

High intake of fat and a low intake of foods rich in antioxidants and fibre are suggested to be associated with risk of colorectal adenomas. Inconsistency may, however, be due to dietary assessment problems or differences in the identification of cases and controls. We have compared 87 adenoma cases aged 50-76 years with 35 healthy controls and 35 'hospital' controls. All the controls were matched for sex and age (+/-5 years) and proven to be free of polyps. Current habitual diet was measured by a 5-day dietary record by weighing. Regarding the intakes of vegetable fat, protein, cholesterol, vitamin A, total vitamin D, edible fats, coffee and fish and fish products, the outcomes of the analysis depended upon the source of controls. However, an increased adenoma risk compared with either set of controls related to a low consumption of vegetables, cereals, iron, vitamin C and fibre and a high intake of total fat was found. This is suggestive of substantial differences, since bias due to abdominal symptoms, the dietary records or an inappropriate choice of controls, would have affected the estimations. The findings give further strength to the role of these dietary factors in the formation of precancerous lesions in the large intestine.

Does high body fatness increase the risk of presence and growth of colorectal adenomas followed up in situ for 3 years?

OBJECTIVE

Obesity is an increasing problem for industrialized nations. The incidence of colorectal cancer has also risen during the last decades. However, information is scarce about the association between the colorectal cancer precursors, adenomatous polyps, and body composition. Our aim was to find out if body fatness is related to the presence of polyps and of growth of adenomas of < or =9 mm observed in situ over 3 yr.

METHODS

Twenty-eight outpatients with colorectal polyps and 50-75 yr of age were compared with 34 sex- and age-matched (+/-5 yr) polyp-free healthy controls. The polyp patients were randomly selected from a double blind 3-yr placebo-controlled endoscopic follow-up and intervention study against growth and recurrence of polyps among 116 polyp-bearing outpatients. Triceps skinfold thickness (TSF) was measured by a Harpenden caliper and total body fat percentage (BF%) by Futrex 5000. Dietary intake was calculated in a 5-day dietary record by weighing. Demograpic data, including smoking and alcohol habits, were registered by an interview and self-administrated questionnaires. Weight and height were measured.

RESULTS

TSF and BF% ranked 66% of the individuals into the same quartiles, and 34% were ranked into the adjacent quartiles. The coefficient of correlation between TSF and BF% was highly significant (r = 0.90, p < 0.01, n = 62). TSF, BF%, and body mass index (kg/m2) did not differ between polyp patients and controls in either crude or adjusted analyses. Adenoma growth was, however, highly associated with increasing levels of TSF (p = 0.004), BF% (p = 0.02), and body mass index (p = 0.006).

CONCLUSIONS

Our data suggest that high body fatness is a promoter of adenoma growth. Similar results were obtained with the caliper and Futrex 5000, which lends credibility to this study. For repeated documentation, a larger study population should be investigated. To our knowledge, this is the first case-control study to investigate the relationship between body composition and growth of adenoma by follow-up in situ over 3 yr.

Results from two repeated 5 day dietary records with a 1 y interval among patients with colorectal polyps

BACKGROUND

Dietary factors are known to be associated with initiation and development of colorectal cancer (CRC), and also with CRC's major precursor, the colorectal polyp. In long-term intervention studies on colorectal polyps, dietary changes may therefore affect potential effects of the study intervention.

OBJECTIVE

To examine potential dietary changes among polyp-patients randomly selected from a 3 y intervention study after 1 y.

DESIGN AND SUBJECTS

Of 116 polyp-bearing out-patients (50% men), aged 50-76 y, who participated in the double-blind 3 y placebo-controlled endoscopic follow-up and intervention study against growth and recurrence of polyps, 30 patients were randomised (strata: sex, age and polyp size) to perform a repeated 5 day dietary record by weighing after 1 y. The patients received a daily mixture of vitamin C (150 mg), alpha-tocopherol (75 mg), beta-carotene (15 mg), selenium (101 microg) and calcium (1.6 g) or placebo (lactose) for a period of 3 y with annual colonoscopic examinations and polyps size measurements to test if the mixture was able to reduce polyp growth and recurrence. Polyps of >9 mm were removed, whereas the remainders and new discoveries of polyps <9 mm were left in situ until the end of the study.

RESULTS

Twenty-nine patients agreed to perform the repeated 5 day dietary record, and 86% performed the second record within 48-58 weeks after the first record. The results showed that, with the exception of vitamin D, milk and milk products, no significant differences were found between the two records. The median value of the Spearman's correlation coefficient for energy and energy-yielding nutrients was 0.66, for vitamins and minerals 0.58, and for foods 0.58. Individual differences between the records were found for most variables, but most of these were negligible.

CONCLUSION

After 1 y, no major dietary changes were found which could be associated with a changed susceptibly for malignancy, and thereby affect potential effects of the study intervention. We may thus suggest that a potential changed susceptibility towards growth and recurrence of polyps, is due to the specific intervention, and not due to other major dietary changes.

Growth and recurrence of colorectal polyps: a double-blind 3-year intervention with calcium and antioxidants

BACKGROUND

Dietary calcium and antioxidants have been suggested as protective agents against colorectal cancer. This has been supported by animal experimental studies, case control and cohort studies.

MATERIALS AND METHODS

In a prospective intervention study of colorectal adenomas, and intermediary stage in colorectal carcinogenesis, 116 polyp-bearing patients received a placebo-controlled daily mixture of beta-carotene 15 mg, vitamin C 150 mg, vitamin E 75 mg, selenium 101 microg, and calcium (1.6 g daily) as carbonate for a period of 3 years with annual colonoscopic follow-up to test if the mixture was able to reduce polyp growth or recurrence. All polyps of < 10 mm at enrollment or follow-up were left unresected until the end of the study.

RESULTS

87-91% of the patients attended the annual endoscopic follow-up investigations, and 19% of the patients dropped out of the medical intervention. The rest consumed 85% of the total amount of tablets over the 3 years. The fecal calcium concentration was 2.3-2.7 times higher in patients taking active medication compared to the placebo group. Diet registration showed that, when adding the intake of antioxidants and calcium from diet and intervention, there was a significant difference between the intake of these substances in the active and the placebo group. No difference was detected in the growth of adenomas between the active and the placebo group from year to year and for the total study period. Moreover, there was no effect on polyps of < 5 or 5-9 mm, or on polyps in the different colonic segments analyzed separately. A reduced growth of adenomas was found in patients <60 years of age taking active medication (n = 8) compared to those taking placebo (n = 6; mean difference 2.3 mm; 95% CI 0.26-4.36). There was a significantly lower number of patients free of new adenomas in the placebo group compared to those taking active medication as tested by logistic regression and Kaplan-Meier analysis (log-rank test p value 0.035). Subgroup analysis showed that only the group of patients with no family history of colorectal cancer, those with only one adenoma at inclusion, and those <65 years benefitted from the intervention medication.

CONCLUSION

The study did not find an overall effect on polyp growth. Our data, however, may support a protective role of calcium and antioxidants on new adenoma formation.

Smoking and colorectal adenomas: a case-control study

A positive association between tobacco and colorectal adenomas has been suggested. Smoking is, however, also associated with 'poor' dietary habits, which in turn may be related to risk of adenomas. It is therefore of interest to study the relationship between smoking, diet and risk of colorectal adenomas in follow-up studies. We compared 87 adenoma cases to 35 'hospital' and 35 healthy controls (all controls were age- and sex-matched and proven to be free of adenomas). Smoking data were collected by an interview and a self-administrated questionnaire with a time interval of at least one month. After 3 years of follow-up, all polyps were removed. Our data indicate that smoking is associated with adenoma prevalence, but not necessarily with size, multiplicity, growth or recurrence of adenomas. Compared to both sets of controls, cases reported to have smoked more than 15 pack-years, or who are current smokers, had a fourfold increased frequency of adenomas (odds ratios 3.6-5.9). Smokers with adenomas had dietary habits that may also be associated with adenomas. The smoking estimates remained largely unchanged even after adjustments for dietary variables in multivariate analysis. This study lends support to the theory of an initiating role of tobacco smoke in neoplasia formation.

The relationship between faecal bile acid profile with or without supplementation with calcium and antioxidants on recurrence and growth of colorectal polyps

Faecal bile acids (FBA) have been implicated in colon carcinogenesis. The results of case-control studies of colorectal cancer and polyp patients are, however, conflicting. The aim of this study was to examine the influence of faecal bile acids on occurrence, growth and recurrence of colorectal polyps, and to see if a mixture of calcium and antioxidants might possibly act on cancer precursors through the effect on FBA. A total of 116 polyp-bearing patients were recruited from the outpatients department. Polyps < 10 mm in diameter were left in situ and measured by annual colonoscopy for 3 years. The patients received placebo or a mixture of antioxidants and calcium carbonate, 1.6 g calcium ion daily. Faecal samples were collected annually; the first, 1 month after start of intervention, freeze dried and subjected to bile acid profile analysis. Two age and sex matched control groups were recruited (n = 35), one from healthy volunteers (healthy controls) and one from the outpatients referred for colonoscopy, with no polyps (hospital controls). Twelve of 47 patients from the healthy volunteers had polyps (healthy polyp patients). One or more adenomas were found in 93 patients. The faeces of the hospital controls had significantly higher concentrations of total and secondary bile acids than did the healthy controls. There was no difference in FBA profile between the polyp group and the hospital controls, but significantly higher concentration of total and secondary faecal bile acids in the healthy polyp patients compared with the healthy control group (P < 0.05). No increased concentration of FBA were found in the polyp patients with multiple polyps (n = 21) or previous treatment for colorectal cancer (n = 7). No associations between FBA profile and growth or recurrence of colorectal polyps were found. The polyp patients receiving active medication had higher faecal concentrations of total and secondary bile acids in the beginning of the study than at the end, in spite of a good compliance. The present study does not support bile acids as being important markers of initiation or growth of small and medium sized colorectal adenomas. In the present study the calcium and antioxidants did not seem to affect the growth or recurrence of colorectal adenomas by increased TBA excretion in the faeces.

[Colorectal cancer. Location dependent symptoms?]

It is claimed that the symptoms of cancer in different parts of the colorectum are varied. The aim of the study was to decide how well the "classical" symptoms are divided between left and right colonic and rectal adenocarcinomas. This was a retrospective study of 102 patients with colorectal cancer at Ullevål hospital in 1992. Red blood in the faeces (p = 0.001), and changes in stool pattern (p = 0.001), were left colonic and rectal cancer specific. Moreover tenesmus, mucous stools, and pain at defecation were specific of rectal cancer. All these findings agree with the textbooks. Melaena, diarrhoea (p = 0.23), weight-loss (p = 0.09), a feeling of general physical weakness (p = 0.13), and ileus/subileus were not found as localisation specific symptoms, contrary to the claims of several textbooks. Pain was always correlated to the affected side in left and right colonic cancer, while in rectal cancer the localisation of pain was non-specific, and it appeared rather often; (37%) in Dukes' A and Dukes' B. Only a few patients had anorexia, but the number was still significant for those with right colonic cancer (p = 0.04). With few exceptions, our results generally support the textbooks. The referring symptoms may help to decide the necessity for further examinations, when total colonoscopy is not obtained.

Growth rate of colon polyps and cancer

Malignancy potential of colorectal polyps increases with size. The growth rate and destiny of each polyp is virtually unknown. It was recently shown that polyps smaller than 10 mm left in situ may partly regress or partly increase in size, whereas one quarter of polyps are unchanged after 3 years. Polyps smaller than 5 mm show a mean increase in size, whereas polyps measuring 5 to 9 mm show a mean decrease in size. Methodologic problems with the measurement of polyps and cancer are discussed. More studies of polyp growth related to risk factors are warranted.

Growth of colorectal polyps: redetection and evaluation of unresected polyps for a period of three years

BACKGROUND, AIMS, AND PATIENTS: In a prospective follow up and intervention study of colorectal polyps, leaving all polyps less than 10 mm in situ for three years, analysis of redetection rate, growth, and new polyp formation was carried out in 116 patients undergoing annual colonoscopy. The findings in relation to growth and new polyp formation were applied to 58 subjects who received placebo.

RESULTS

Redetection rate varied from 75-90% for each year, and was highest in the rectum and sigmoid colon. There was no net change in size of all polyps in the placebo group, however, polyps less than 5 mm showed a tendency to net growth, and polyps 5-9 mm a tendency to net regression in size, both for adenomas and hyperplastic polyps. This pattern was verified by computerised image analysis. Patients between 50 and 60 years showed evidence of adenoma size increase compared with the older patients, and the same was true for those with multiple adenomas (four to five) compared with those with a single adenoma. The new adenomas were significantly smaller and 71% were located in the right side of the colon. Patients with multiple adenomas had more new polyps at all the follow up examinations than patients with a single adenoma. One patient developed an invasive colorectal carcinoma, which may be evolved from a previously overlooked polyp. Two polyps, showing intramucosal carcinoma after follow up for three years, were completely removed, as judged by endoscopy and histological examination.

CONCLUSIONS

The results show that follow up of unresected colorectal polyps up to 9 mm is safe. The consistency of growth retardation of medium sized polyps suggests extended intervals between the endoscopic follow up examinations, but the increased number of new polyps in the proximal colon indicates total colonoscopy as the examination of choice. The growth retardation of the medium sized polyps may partly explain the discrepancy between the prevalence of polyps and the incidence of colorectal cancer.

Secretory component mRNA and protein expression in colorectal adenomas and carcinomas

Secretary component (SC) is expressed basolaterally as a transmembrane protein (pIg receptor) on secretory epithelial cells. As pIg receptor it plays a central role in humoral immunity by mediating the external translocation of dimeric IgA and pentameric IgM. A few case reports have suggested that reduced or absent SC protein expression is associated with diarrhoeal disease, but there is no convincing evidence that a primary pIg receptor deficiency can occur. In this study the relative presence of SC mRNA was determined by Northern blot analysis and related to immunohistochemically determined SC protein expression in 33 colorectal adenomas (31 patients) with increased risk of developing sporadic colorectal cancer, as well as in 19 colorectal carcinomas from 19 patients with such sporadic tumours. In the adenomas, SC mRNA levels were positively related to SC protein expression; both mRNA and SC protein were negatively related to histological grade. Similarly, SC mRNA levels tended to be related to the SC protein expression in the carcinomas. SC mRNA was detected in all adenomas, and only two of ten carcinomas (10.5%) deemed to be SC deficient by immunohistochemistry also lacked SC mRNA expression, suggesting diallelic alterations in the SC-encoding gene (locus PIGR). This possibility agreed with Southern blot analysis performed on a separate sample of 32 other colonic carcinomas in which the diallelic loss of D1S58 (which exhibits a close linkage centromerically to PIGR) was calculated to be 6.4%. Together these findings suggested that reduced SC protein expression in colorectal adenomas might be a transcriptional defect reflecting the degree of cellular dysplasia, whereas absent SC protein expression in colorectal carcinomas might also involve post-transcriptional defects and occasional diallelic gene deletions representing late events in carcinogenesis.

Deletion of 1p loci and microsatellite instability in colorectal polyps

Previous cytogenetic studies have indicated that a subset of large bowel adenomas have distal 1p deletions. We addressed this question by examining 70 sporadic polyps (63 adenomas, 5 hyperplastic polyps, and 2 polyps of undetermined histology) from 55 patients for alterations at eight loci on the short arm of chromosome 1 and found allelic imbalance (AI) or loss of one allele (LOH) in 14 (20%). The locus most frequently changed was MSI, which maps to 1p33-35. Fluorescence in situ hybridisation with centromeric and telomeric probes for chromosome 1, performed for 11 polyps, did not yield an abnormal number of signals, in accordance with the interpretation that the observed AI and LOH were the result of interstitial deletions in 1p. Whereas allelic imbalance at five other loci (mapping to 5q, 8p, 10p, 11p and 17q) was found less frequently, and then mainly in large (> 2 cm) tumours, the 1p alterations were equally distributed among small (< 1 cm) and large polyps. They were preferentially found in left-side tumours. Instability at microsatellite loci--the mutator phenotype--is demonstrated by shifts in the electrophoretic mobility of normal alleles. The mutator phenotype was first associated with hereditary nonpolyposis colorectal cancer but is also occasionally found in sporadic colorectal carcinomas; however, it is still uncertain when in the adenoma-carcinoma sequence in this type of genomic instability arises. We therefore looked for it at 12 dinucleotide repeat loci and found that seven tumours (six adenomas and one hyperplastic polyp) from seven patients had acquired new alleles not seen in the patients' corresponding normal DNA. Our results suggest that inactivation of a putative suppressor gene distally in chromosome arm 1p is an early event in colorectal tumourigenesis. They also show that microsatellite instability can be detected in large bowel polyps, indicating that this phenomenon, too, probably plays a pathogenic role for some colorectal tumours early in the adenoma-carcinoma sequence.

Dietary factors and colorectal polyps: a case-control study

In the case-control study we compared dietary habits among 108 patients with small (< or = 5 mm, n = 26), medium (5-9 mm, n = 48) or large (> or = 10 mm, n = 34) colorectal polyps with 35 healthy age- and gender-matched controls. A food record by weighing during 5 consecutive days was performed. The intake of fat was significantly higher among the patients, in contrast to a significantly lower intake of carbohydrate, dietary fibre and iron, compared with controls. The intake of vitamin C and calcium was shown to be lower among the patients, but this was significant only for women. There was a tendency among the patients to consume a lower-antioxidant, fibre and cereal fibre diet, and a calcium-rich and more cholesterol-rich diet with increasing size of polyps. The patients with the smallest polyps tended to consume less starch. Our results are too preliminary to draw conclusions with regard to the influence of nutritional factors on the size and growth of polyps. However, our risk factors for the presence of polyps are in agreement with previous studies. Further studies taking into account the size of the polyp are needed to corroborate our findings.

Growth of colorectal polyps: recovery and evaluation of unresected polyps of less than 10 mm, 1 year after detection

BACKGROUND AND METHODS

Colonoscopic 1-year control of polyps of less than 10 mm left in situ was carried out in 103 (89%) of 116 originally examined patients.

RESULTS

Analysis showed an 85% recovery: 91% and 81% for polyps of 5-9 mm and < 5 mm, respectively. The recovery was significantly related to size and localization, whereas the growth rate was inversely correlated to the originally measured diameter. A linear relationship was demonstrated between anus-to-polyp distances 1 year apart, with a normalized agreement index of 0.70. In only 1 of 189 polyps, an increase of diameter to > 10 mm was demonstrated. The 79 new polyps in 52 (50%) of the patients were significantly smaller, more often right-sided, and related to multiplicity of polyps at the initial examination but not to growth of recovered polyps or cleansing status.

CONCLUSION

An acceptable recovery and growth rate of polyps < 10 mm seems to justify the continuation of the study for the remaining 2 years.

In situ measurement of colorectal polyps to compare video and fiberoptic endoscopes

The present study was performed to test the reliability of in situ measurements of colorectal polyps when comparing videoendoscopes with fiberoptic endoscopes. In 25 small rectosigmoid polyps 3-12 mm) removed endoscopically, in situ diameters were measured before polypectomy using both video- and fiberoptic endoscopes. Polaroid and videoprint pictures were taken for computerised analysis of the area of the polyps on the pictures. The results showed a good correlation between the polyp diameter measured with the videoendoscope and fiberoptic endoscope (r = 0.97), with no significant difference by parametric testing. The diameter and weight of the removed polyp also correlated well with the diameter measured in situ using videoendoscopes (r = 0.92 and 0.77, respectively) or fiberoptic endoscopes (r = 0.90 and 0.81, respectively). Furthermore, the weight of the removed polyp correlated reasonably well to the computerised area measurement, the correlation coefficient being r = 0.90 for fiberoptic endoscopes and r = 0.75 for videoendoscopes. We conclude that in situ polyp diameter measurements using videoendscopes and fiberoptic endoscopes are similarly reliable and sensitive, and both instruments can be used interchangeably in follow-up studies of polyp growth.

Growth of colorectal polyps: design of a prospective, randomized, placebo-controlled intervention study in patients with colorectal polyps

One hundred and sixteen patients were included, during 18 months, in a double-blind placebo-controlled intervention study, with calcium, vitamins A, C, E and selenium (in a cocktail) or placebo against growth of colonic polyps. Patients were randomized within three arms, according to diameter of the largest polyp, < 5 mm, 5-9 mm or > 9 mm. Polyps > 9 mm were resected, the others were left to be measured annually before resection after 3 years. The protocol (performed in all of the patients) included registration of demographic data, family and personal history, measurement of polyps, collection of blood specimens, stools and biopsy samples. Registration of nutritional status, diet history and 5-day prospective food consumption, was performed in 108 patients. The patient compliance was registered every third month by the hospital pharmacist, with concomitant delivery of new boxes of capsules. Additionally, stool collections were performed from all of the patients for the measurement of faecal calcium, bile salts and fat. Inclusion rate of 37, 41 and 38 patients in each of the three 6-month periods was uniform. The group with the largest polyps measuring 5-9 mm comprised 44% of the material. The sex ratio corresponded to that in overall referrals for colonoscopy. The age relationship of size and multiplicity of polyps and the distribution of polyps in the large bowel corresponded to previous experience in polyp-bearing individuals of the same age.(ABSTRACT TRUNCATED AT 250 WORDS)

Does preoperative anxiety influence gastric fluid volume and acidity?

Preoperative anxiety may increase gastric fluid acidity and volume. To pursue this possibility we evaluated the relationship between peroral premedication, preoperative anxiety, and gastric content in 246 consecutive patients presenting for elective gynecologic surgery. All patients fasted overnight and received either flunitrazepam 1 mg, oxazepam 25 mg, or placebo with 20 mL of water on the morning of surgery in a randomized, double-blind fashion. The patients assessed relief of anxiety using a four-graded scale (excellent, good, fair, poor). Both flunitrazepam and oxazepam decreased anxiety (P less than 0.01) compared with placebo. However, no correlations between type of premedication or level of anxiety and gastric contents were found. The proportion of patients with gastric fluid volume greater than 25 mL and pH less than 2.5 was not significantly different in any of the groups studied. These results suggest that neither peroral benzodiazepine premedication nor preoperative anxiety have a clinically important impact on gastric content in patients presenting for elective gynecologic surgery.

[Development and use of a database for gastroenterologic endoscopy]

With no commercially available endoscopy database manager available, a standalone system for gastroenterological endoscopy departments has been developed since 1985 through joint efforts of gastroenterologists and dedicated programmers. The present system was implemented for daily use January 1989 and, to date, approximately 19,000 examinations have been recorded. Nurses and office assistants carry out administrative work, but the physician enters the endoscopic data, partly as free text, partly as structured data via automated menus and a mouse. In addition to the immediate printout of the result, valuable data are stored in the computer for administrative and research purposes. Mean data entering time for the physician was four minutes 17 seconds, and altogether eight minutes 40 seconds was spent on the computer system for each patient served.

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.

SADE database for endoscopic procedures: aspects of clinical use

The time aspects of daily use of a clinical database system in an endoscopy department were studied. The SADE database system for endoscopic procedures was introduced for daily use at Ullevål Hospital on 1 January 1989. The average weekly programme of the endoscopy unit includes 57 gastroduodenoscopies, 23 colonoscopies and 12 ERCP/EPTs. During three consecutive weeks of the study the mean physician input time was 4 min 17 sec per patient (range 57 sec to 15 min), individual variation depending mainly on the extent of the report. Assistants spent a mean time of 4 min 23 sec for each patient. Thus, a total of 8 min 40 sec was spent for every patient seen. Endoscopic units should analyze their routines and needs before introducing an electronic data base manager.

The SADE system: an endoscopic database manager

The development of the SADE database manager was commenced in 1985 since no commercially available systems were suited for the needs of a large endoscopy unit. Over a period of five years, this database was programmed, revised and enhanced through the joint efforts of gastroenterologists and programmers, the SADE system being implemented for daily use on 1 January 1989. The patient administration and medical record modules are fully implemented and functional, while the statistical module has only recently been finished. The present features of the system are described, and the limitations discussed. Instant report generation and direct access to previous medical data are the most immediate benefits of the system. The initial intention to have structured anamnestic data had to be modified to suit the need for flexibility and ease of free text input by the users.

Comparison of the gastrointestinal side effects of naproxen formulated as plain tablets, enteric-coated tablets, or enteric-coated granules in capsules

We studied the gastrointestinal side effects of three formulations of naproxen in 18 healthy male volunteers. In a Latin-square design crossover study, the subjects received 500 mg naproxen twice daily for 7 days as plain tablets, enteric-coated tablets, or enteric-coated granules in capsules. The 51Cr-EDTA absorption test was performed before and at the end of each drug period, to evaluate changes in the distal gut. The test dose was instilled distally in the duodenum to prevent lesions in the stomach from interfering with the evaluation. Upper endoscopy was performed at the same intervals, scoring changes in the middle and distal duodenum separately from findings in the stomach and duodenal bulb. The nature and severity of adverse effects were recorded for each treatment period. Non-parametric methods were used for statistical evaluation. All drugs induced a significant increase in 51Cr-EDTA absorption, but we did not detect any difference between the three formulations. All formulations were associated with a significant increase in all the endoscopic findings monitored. Enteric-coated tablets induced significantly less lesions than enteric-coated granules in the stomach and duodenal bulb, and an advantage over plain tablets was indicated. No difference was seen in the middle and distal duodenum. The proximal endoscopic scores were not correlated to those found in the middle and distal duodenum. Evaluation of the small and large bowel should probably be included in clinical studies of NSAIDs, but our findings suggest that the importance of transfer of mucosal lesions to the distal gut by enteric coating may have been overemphasized.

Benzodiazepines as oral premedication. A comparison between oxazepam, flunitrazepam and placebo

Oxazepam 25 mg, flunitrazepam 1 mg and placebo were compared as oral premedication in 602 gynecological patients in a double-blind randomised parallel study. In 251 patients undergoing major surgery the same drug was also given as a hypnotic the night before the operation. Both active drugs shortened the sleep-onset time, decreased the number of spontaneous awakenings at night and improved the quality of sleep when compared to placebo. The active drugs were significantly better than placebo as premedication when assessed by both the patients and the anesthesiologist. In 351 patients admitted for day-case minor surgery with no previous night medication, flunitrazepam was significantly better than placebo as premedication when assessed by both the patients and the anesthesiologist, while oxazepam was only better than placebo when judged by the anesthesiologist, not by the patients.