Predictors of the early development of advanced metachronous colon adenomas

BACKGROUND/AIMS: In order to reduce the number of colonoscopies performed for the surveillance of patients after polypectomy, suitable predictors of adenomas recurrence are needed. The aim of this study was to find predictors of the early development of metachronous adenomas and specifically of advanced ones. MATERIALS AND METHODS: Forty-four patients underwent total colonoscopy 24-26 months after initial endoscopic polypectomy. All polyps were endoscopically removed and an adenoma was considered as advanced if the diameter was > 1 cm and/or villous component and/or severe dysplasia were present. RESULTS: Metachronous adenomas were detected in 16 (36.4% patients. Five (11.4%) of them had advanced metachronous adenomas. Early recurrence of adenomas was significantly correlated with the total number of indices adenomas (p = 0.027). On the contrary, the presence of metachronous adenomas was not related to any of the patients' characteristics nor to the site and the histology of the indices adenomas. The development of advanced metachronous adenomas during the same period was significantly correlated with patients' age, as it was observed only in patients aged > or = 60 years (5/21 or 23.8%) and in none of the patients aged < 60 years (Odds ratio: 15.7, p = 0.02). Logistic regression analysis revealed that patient's age was the only significant predictor of the early development of advanced metachronous adenomas (beta = 0.40, p = 0.02) and that the number of the indices adenomas was the only significant predictor for the recurrence of all adenomas (beta = 1.59, p = 0.02). CONCLUSIONS: 1. Only patients aged > or = 60 years seem to develop advanced metachronous adenomas two years after polypectomy and 2. The likelihood for developing metachronous adenomas during the same period is related to the number of indices adenomas.     

Pathologic features of initial adenomas as predictors for metachronous adenomas of the rectum

BACKGROUND: Colorectal cancer is the third most common cancer in the world, arising mostly from pre-existing adenomatous polyps (adenomas) of the large bowel. Patients with colorectal adenomas are at increased risk of colorectal cancer because of a high recurrence rate for adenomas. We followed a cohort of 1490 patients with rectal adenomas to determine whether recurrence might be related to pathologic characteristics of the initial adenomas. METHODS: The patients were identified in Haining County, China, from 1977 through 1978 by means of examination with a 15-cm rigid sigmoidoscope. They were followed by endoscopic examination at years 2, 4, 6, 11, and 16 after their initial polypectomy. New adenomas in the rectum were identified in 280 patients in these follow-up examinations. RESULTS: Statistically significant twofold to threefold elevated risks of metachronous (recurrent) adenomas were observed for patients who had more than two initial adenomas or whose most advanced initial adenoma was more than 1.0 cm in size, was of villous/tubulovillous type, or showed moderate to severe dysplasia. Much stronger associations were observed for advanced metachronous neoplasms, which are defined as cancers or adenomas with severe dysplasia, with multivariate adjusted relative risks (95% confidence interval) of 4.2 (1.8-9.9) for a large initial adenoma (>1.0 cm), 8.1 (4.2-15.6) for villous/tubulovillous architecture, and 14.4 (5.0-41.3) for severe dysplasia. In particular, patients who had a large (>1.0 cm) adenoma with severe dysplasia at baseline had a relative risk of 37 (7.8-174.7) of developing advanced metachronous neoplasms compared with patients who had small adenoma(s) with mild dysplasia. CONCLUSIONS: The risk of metachronous adenomas is closely related to the pathology of initial adenomas, thus allowing identification of a high-risk group of adenoma patients for close surveillance after their initial polypectomy.     

Use of peripheral quantitative computed tomography for densitometry of the femoral neck and spine in cynomolgus monkeys (Macaca fascicularis)

BACKGROUND AND METHODS: Laboratory, clinical, and epidemiologic evidence suggests that calcium may help prevent colorectal adenomas. We conducted a randomized, double-blind trial of the effect of supplementation with calcium carbonate on the recurrence of colorectal adenomas. We randomly assigned 930 subjects (mean age, 61 years; 72 percent men) with a recent history of colorectal adenomas to receive either calcium carbonate (3 g [1200 mg of elemental calcium] daily) or placebo, with follow-up colonoscopies one and four years after the qualifying examination. The primary end point was the proportion of subjects in whom at least one adenoma was detected after the first follow-up endoscopy but up to (and including) the second follow-up examination. Risk ratios for the recurrence of adenomas were adjusted for age, sex, lifetime number of adenomas before the study, clinical center, and length of the surveillance period. RESULTS: The subjects in the calcium group had a lower risk of recurrent adenomas. Among the 913 subjects who underwent at least one study colonoscopy, the adjusted risk ratio for any recurrence of adenoma with calcium as compared with placebo was 0.85 (95 percent confidence interval, 0.74 to 0.98; P=0.03). The main analysis was based on the 832 subjects (409 in the calcium group and 423 in the placebo group) who completed both follow-up examinations. At least one adenoma was diagnosed between the first and second follow-up endoscopies in 127 subjects in the calcium group (31 percent) and 159 subjects in the placebo group (38 percent); the adjusted risk ratio was 0.81 (95 percent confidence interval, 0.67 to 0.99; P=0.04). The adjusted ratio of the average number of adenomas in the calcium group to that in the placebo group was 0.76 (95 percent confidence interval, 0.60 to 0.96; P=0.02). The effect of calcium was independent of initial dietary fat and calcium intake. CONCLUSIONS: Calcium supplementation is associated with a significant - though moderate - reduction in the risk of recurrent colorectal adenomas.     

Pneumocephalus and respiratory depression after accidental dural puncture during epidural analgesia--a case report

BACKGROUND: Adenomatous colonic polyps are accepted as premalignant lesions. There is controversy regarding the significance of the hyperplastic polyp. The aim of this study was to determine the incidence of further polyps in patients with only hyperplastic polyps on a first colonoscopy in comparison with patients without polyps and with adenomatous polyps. METHODS: Ninety patients had only hyperplastic polyps (group I). These patients were paired according to age and sex with subjects having no polyps (group II) and with patients having adenomas (group III). RESULTS: Fifty-six patients in group I had at least one follow-up examination. New polyps were found in 46.4% in group I versus 15.5% in group II (p < 0.001) and 50% in group III (NS). In group I, 30.7% of new polyps were hyperplastic and 69.3% were adenomas. In fact, 32.2% of group I patients developed further adenomas (mean 1.5 +/- 0.8 adenomas). These adenomas occurred 1 to 4 years after the first polypectomy (mean 2.4 +/- 0.8 years). Most of these adenomas were small and tubular, but 16.6% were villous or had severe dysplasia. CONCLUSION: Patients with hyperplastic polyps were 2.4 times more likely to have further adenomas than were those without polyps.     

Flat adenoma as a precursor of colorectal carcinoma in hereditary nonpolyposis colorectal carcinoma

BACKGROUND: Because flat adenoma shows a higher malignancy rate compared with other types of polyps, it is considered to play an important role in the carcinogenesis of colorectal carcinoma. In the present study, we examined flat adenomas in hereditary nonpolyposis colorectal carcinoma (HNPCC) patients. METHODS: Nine HNPCC patients who presented with flat adenomas were examined. All patients underwent either surgery or endoscopic polypectomy for colorectal carcinoma and/or adenoma. In all patients, annual colonoscopy had been performed once a year throughout the follow-up period after the initial treatment. When colorectal polyps were detected during follow-up colonoscopy, all lesions were endoscopically excised. Clinicopathologic features and microsatellite instability of both malignant lesions and adenomas were examined. RESULTS: Thirteen malignant lesions were detected: seven advanced carcinomas and six early carcinomas. Among 4 early carcinomas with submucosal invasion, 3 lesions (75%) were categorized as superficial type, with a configuration similar to flat adenoma. The frequency of flat adenoma was strikingly high in HNPCC patients in the present study. Among 73 polyps detected, 37 (50.7%) were flat adenomas. Both malignant lesions and flat adenomas had proximal predominance, 61.5% and 59.5%, respectively. Eleven of 15 lesions (73.3%) showed replication error. CONCLUSIONS: These results suggest the importance of flat adenoma as a precursor of colorectal carcinoma in some groups of HNPCC patients. Further study is essential to elucidate the natural history of flat adenomas in HNPCC patients.     

A prospective evaluation of the safety and efficacy of methohexital in the emergency department

OBJECTIVE: Knowledge of a possible correlation between distal polyps found at screening sigmoidoscopy and proximal colonic lesions is important for deciding whether to perform total colonoscopy or not. PATIENTS: A prospective analysis of 2439 consecutive patients with colorectal polyps. Of these, 304 were asymptomatic subjects who underwent complete colonoscopy for screening and were found to have adenomatous or hyperplastic polyps in the distal colorectum. RESULTS: Ten (15%) out of 65 patients with distal hyperplastic polyps only and 86 (36%) out of 239 with distal adenomatous polyps were found to have adenomatous polyps in the proximal colon as well (P < 0.001). The frequency of synchronous proximal adenomas in patients with small (< or = 5 mm) or large distal adenomas (> 5 mm) was comparable (37% and 35%, respectively). However, patients with small distal adenomas had significantly smaller proximal adenomas (P = 0.004) containing less villous component (P = 0.017) than those with large distal adenomas. Neither the patient's age nor the presence of multiple distal adenomas increased the prevalence of proximal adenomas. CONCLUSION: Hyperplastic polyps found on rectosigmoidoscopy do not indicate a need for a complete colorectal examination, as 15% of patients with distal hyperplastic polyps will have proximal adenomatous polyps, a figure that is comparable with that of asymptomatic patients having no distal polyps, either hyperplastic or adenomatous. When only small distal adenomas are found at screening sigmoidoscopy in asymptomatic persons the decision to do a total colonoscopy should be based on individual considerations, as in such cases only small polyps are to be expected in the proximal colon.     

A truncated poisson regression model with applications to occurrence of adenomatous polyps

Adenomatous polyps are considered as the dominant precursor lesion of colorectal cancer. A phase III colorectal cancer prevention trial, conducted by the Arizona Cancer Center, concerns the ability of wheat bran fibre supplement to reduce the recurrence of adenomatous polyps. All participants in the study are to have had colorectal polyps detected and removed during a baseline (qualifying) colonoscopy within three months prior to enrolment. In this paper, our interest focuses on occurrence of adenomatous polyps at the baseline colonoscopy. We use a truncated Poisson model to fit these types of data. We develop a regression model to assess the effects of explanatory factors on the positive counting variable. We fit truncated Poisson parameters by a log-linear regression model and estimate regression parameters by the maximum likelihood procedure. Finally, we apply it to the baseline colonoscopy data from the Wheat Bran Fiber study.     

Central nervous system (CNS) involvement in SLE. The diagnostic role of antibodies to neuronal antigens

Dysplasia in inflammatory bowel disease (IBD) is categorized as either flat or associated with a raised lesion or mass (dysplasia-associated lesion or mass [DALM]). One specific subtype of a dysplasia-associated lesion or mass consists of isolated discrete nodules or polyps that are difficult to distinguish from sporadic adenomas. Because the clinical management of these two lesions is different, we performed this study to (1) evaluate the clinical presentation, pathologic features, and natural history of polypoid dysplastic lesions and sporadic adenomas in patients with IBD and (2) determine whether there are clinical, endoscopic, or pathologic findings useful in differentiating between these two lesions. The morphologic features of 89 benign polypoid epithelial neoplasms from 59 patients with IBD (51 with ulcerative colitis, 8 with Crohn's colitis) were evaluated and correlated with the clinical, endoscopic, and follow-up data. In a separate analysis, patients were categorized arbitrarily as having (1) a probable sporadic adenoma if the polypoid epithelial neoplasm was not located within areas of histologically proven colitis, (2) a probable IBD-associated polypoid dysplasia if the lesion developed within an area of colitis, and associated flat dysplasia or an adenocarcinoma was detected during follow-up evaluation or (3) an indeterminate polyp, which was seen in the remainder of the cases. The clinical, endoscopic, and histologic data were compared among these three patient and polyp subgroups. There were 35 males and 24 females (median age, 57 years; range, 27-85 years). Median duration of disease was 10 years. Forty-nine percent of the patients had pancolitis; 66% had histologically active disease at the time of presentation. Nearly 70% of patients had only one polyp; the majority occurred in either the left colon or the rectum (66%). Most polyps were described as a sessile nodule, whereas only 7 (7.8%) were pedunculated. Polyps ranged from 2 mm to 50 mm (median, 5 mm); most had a tubular architecture (84.3%) and contained low-grade dysplasia (64%). In addition, most polyps had mildly increased lamina propria and intraepithelial neutrophilic and mononuclear inflammation. At follow-up evaluation (40 patients; median follow-up time, 13 months; range, 1-78 months), a further neoplastic lesion developed in 20%; low-grade flat dysplasia was seen in 5 (12.5%), and adenocarcinoma developed in 3 (7.5%). However, dysplasia or adenocarcinoma did not develop in the patients who had polyps located outside of areas of histologically proven colitis. In addition, at least one more benign polypoid epithelial neoplasm developed in 15 of 40 patients (37.5%). Patients with probable IBD-associated polypoid dysplasia had a statistically significant (p < 0.05), longer disease duration than patients with probable sporadic adenoma. A statistically significant, higher proportion of polyps with tubullovillous or villous architecture, an admixture of normal and dysplastic epithelium at the surface of the polyps, and increased lamina propria mononuclear inflammation was noted in probable IBD-associated polypoid dysplastic lesions compared with those considered to be sporadic adenomas. Several clinical and pathologic features may be useful to help categorize a polypoid dysplastic lesion as a sporadic adenoma or an IBD-related neoplasm in a patient with IBD. This distinction is important because the natural history of these two lesions (as shown by the results of this study) and their subsequent management are quite different.     

Co-expression of polyhydroxyalkanoate synthase and (R)-enoyl-CoA hydratase genes of Aeromonas caviae establishes copolyester biosynthesis pathway in Escherichia coli

Arylamine N-acetyltransferase 2 (NAT2) is involved in both the detoxification and bioactivation of carcinogenic arylamines and other mutagens. This enzyme is polymorphic, and the fast and slow phenotypes are thought to be risk factors for colon and bladder cancer, respectively. Here, we report on a case-control study of adenomatous and hyperplastic polyps, with particular attention to tobacco smoking, a known risk factor for adenomas, and polymorphisms of NAT2. All participants underwent complete colonoscopy and were subsequently divided into case and control groups on the basis of pathology. Cases were diagnosed with confirmed adenomas (n = 527) or hyperplastic polyps (n = 200); controls (n = 633) had no history of colonic neoplasia and no polyps at colonoscopy. NAT2 genotype was determined using an oligonucleotide ligation assay and fast, intermediate, or slow phenotype imputed. Multivariate-adjusted odds ratios (ORs) and 95% confidence intervals were computed using logistic regression adjusting for age, sex, nonsteroidal anti-inflammatory drug use, and hormone replacement therapy use. Smoking was associated with an increased risk of adenomas [current versus never smoking OR = 2.0 (95% confidence interval, 1.4-2.9)] and hyperplastic polyps [current versus never smoking OR = 4.1 (2.6-6.5)]. NAT2 status among adenomatous polyp patients and hyperplastic polyp patients, respectively, showed ORs of 1.1 (0.8-1.4) and 1.2 (0.8-1.6; intermediate versus slow) and 1.1 (0.6-1.9) and 0.9 (0.4-1.9; fast versus slow). There were no differences in risk when adenoma patients were stratified on multiplicity, size, or histopathological subtype of polyps. Never-smokers showed no variation in risk across acetylator status for either species of polyp, whereas current smokers showed ORs of 2.0 (1.2-3.2) and 2.3 (1.4-3.9) for adenomas and 3.9 (2.1-7.1) and 4.9 (2.6-9.4) for hyperplastic polyps for slow and intermediate/fast NAT2, respectively, compared with slow-NAT2 never-smokers. Risks of both multiple [OR = 4.3 (2.1-8.8)] and large [OR = 3.8 (1.9-7.5)] adenomas were somewhat elevated in current smokers with an intermediate/fast phenotype compared with smokers with a slow NAT2 phenotype, but the interaction was not statistically significant. Risk of hyperplastic polyps and adenomatous polyps is strongly related to smoking. There is little suggestion of interaction between NAT2 status and smoking and no relationship with NAT2 genotype alone.     

Emptying of colon prior to colonoscopy. A comparison between emptying using peroral polyethylene glycol-electrolyte and conventional emptying with dietary restrictions, laxatives and water lavage

The purpose of the study was to compare the degree of bowel emptying at colonoscopy after preparation with either traditional water enema, dietary restrictions and laxatives or after oral lavage solution (Klean-Prep). Colonoscopy was performed in 104 patients over a two month period, 56 patients being allocated to the conventional preparation and 48 to Klean-Prep. The quality of bowel emptying was evaluated visually during endoscopy and by the proportion of incomplete colonoscopies. Bowel emptying was less satisfactory after Klean-Prep (p = 0.018) and seven incomplete colonoscopies resulted in contrast to two after conventional preparation. The results were obtained from a surgical department with a permanent small staff of motivated nurses preparing a huge number of patients for colonoscopy. No economic advantages could be demonstrated by the use of Klean-Prep.     

K-RAS-2 gene mutations as predictors of metachronous colorectal adenomas

BACKGROUND: Mutations of K-RAS-2 gene and tumour suppressor genes have been found in both colorectal adenomas and carcinomas. The aim of this study was to investigate the prognostic value of K-RAS-2 gene mutations found in initial colorectal adenomas for predicting the risk of metachronous adenomas. METHODS: Genomic DNA was extracted from formalin-fixed and paraffin-embedded adenomas larger than 5 mm in diameter removed at the initial total colonoscopy between 1980 and 1982. All patients underwent colonoscopic follow-up for at least 10 years. The sequence of exon 1 of the K-RAS-2 oncogene was amplified with the polymerase chain reaction technique and screened for mutation by single-strand conformation polymorphism analysis. All suspected mutations were confirmed by direct DNA sequencing. The predictive value of K-RAS-2 gene mutations for the risk of metachronous adenomas was assessed by chi-square testing and logistic regression analysis. RESULTS: Of 54 patients 39 (72%) were male and 15 (28%) female. At the time the initial adenoma was removed, 31 (57%) patients were younger than 60, whereas 23 (43%) were 60 years or older. Point mutations of the K-RAS-2 oncogene were found in the index adenomas of 15 (27.7%) patients. Mutations were found more frequently in large (> or = 20 mm) adenomas and in adenomas with severe dysplasia (P = 0.0011 and P = 0.0310, respectively). There were no significant associations between K-RAS-2 mutations and anatomic location, histologic type, or number of synchronous initial lesions. Mutations were found predominantly at codon 12 with transversions from GGT to GTT (57%), from GGT to GAT (36%), and from GGT to TTT (one patient). The single mutation found at codon 13 showed a transversion from GGC to GAC. There were significant associations between size (> or = 20 mm) and K-RAS-2 mutation of the initial adenomas and the size (> 5 mm) of metachronous adenomas (P = 0.0259 and P = 0.0265, respectively). However, multivariate analysis showed that K-RAS-2 mutations did not provide a significant additional contribution to the prognostic value of the size of the initial adenoma (odds ratio, 7.62; 95% confidence interval (CI), 1.68-34.48) and the amount of villous structure (odds ratio, 0.22; 95% CI, 0.05-0.90) it contained. CONCLUSIONS: Patients with large (> or = 20 mm) adenomas and adenomas with K-RAS-2 mutations found at the initial examination have a significantly higher risk of developing large (> 5 mm) metachronous adenomas during surveillance. Multivariate analysis of initial adenoma characteristics showed that the risk of metachronous colorectal adenomas can be adequately estimated by the size and the histologic type of the largest initial adenoma and that K-RAS-2 mutations are of secondary importance only. Further studies based on a larger series will have to identify the adenoma characteristics that will help to improve follow-up strategies.     

Cigarette smoking and the colorectal adenoma-carcinoma sequence: a hypothesis to explain the paradox

As recognized precursor lesions to colorectal cancer, colorectal adenomatous polyps have been studied to enhance knowledge of colorectal cancer etiology. Although most of the known risk factors for colorectal cancer are also associated with the occurrence of colorectal adenomas, cigarette smoking has had a strong, consistent relationship with colorectal adenomas but is generally not associated with colorectal cancer. The explanation for this paradox is unknown. With data collected in 1986-1988 during a large case-control study based on colonoscopy results in New York City, New York, the authors investigated the possibility that the paradox may arise because subjects with colorectal adenomas were included in the control group of cancer case-control studies. The authors found a statistically significant increased risk between heavy cigarette smoking (smokers with > or = 40 pack-years of smoking) and risk of adenoma (odds ratio (OR) = 1.61, 95% confidence interval (CI) 1.06-2.44). They saw no increased colorectal cancer risk from heavy cigarette smoking (OR = 1.02, 95% CI 0.52-1.99) using a "manufactured" control group to simulate a typical unscreened, population-based control group. When the authors compared these colorectal cancer cases with an adenoma-free control group examined by colonoscopy in a polytomous model with several case groups (newly diagnosed adenomas, carcinoma in situ, intramucosal carcinoma, and colorectal cancer), they found that the risk for 20-39 pack-years of smoking was elevated, although not statistically significant, and was similar for all four case groups. The risk for the highest smoking category (> or = 40 pack-years) was more strongly elevated in all four case groups, although it was statistically significant for only the newly diagnosed adenoma and the carcinoma in situ cases (adenomas, OR = 1.59, 95% CI 1.05-2.42; carcinoma in situ, OR = 2.05, 95% CI 1.01-4.15; intramucosal carcinoma, OR = 1.30, 95% CI 0.61-2.77; and colorectal cancer, OR = 1.30, 95% CI 0.64-2.65). While the authors' study is weakened by the lack of statistical significance concerning risk for colorectal cancer, these data offer some support for the hypothesis that the association between cigarette smoking and risk of colorectal cancer may have been masked by inclusion in the control group of subjects with adenomas. They also suggest that the major effect of smoking on the colorectal adenoma-carcinoma sequence occurs in the earlier stages of the formation of adenoma and the development of carcinoma in situ.     

Pediatric colonoscopy

The procedure and results of 50 colonoscopies performed over a three-year period on a group of 43 children (range: 0.3-16 yr; median: 9 yr) are described. The main indications were evaluation for, or control of already known, chronic inflammatory bowel disease (n = 38) and rectal bleeding (n = 8). Following verbal and written information the children were admitted one to two days before the procedure for bowel preparation. Children < 10 years old received general anaesthesia during the colonoscopy (n = 25) and most children > or = 10 years old received an intravenous sedation with pethidine and midazolam (n = 25). In only one case was intravenous sedation not successful. The coecum was visualised in 96% and the terminal ileum intubated in 77% (when intended) of the endoscopies. The most important results obtained were establishment of the diagnosis of inflammatory bowel disease in 21 of 30 suspected cases and the removal of a polyp in two cases. At the time of colonoscopy a "best guess" diagnosis of either ulcerative colitis or Crohn's disease often predicted the histological diagnosis, but endoscopy tended to underestimate the severity and extent of the inflammation as compared to microscopy. There were no complications. We conclude that colonoscopy performed according to our recommendations is a safe and informative procedure for evaluation of the large bowel and terminal ileum in children with intestinal disease.     

Methylene tetrahydrofolate reductase C677T genotype and stroke

Among 2087 patients who underwent primary resection of colorectal cancer in our department within the past 20 years, 68 (3.2%) were found to have a secondary or additional cancer in their large bowel after the first resection. Statistically significant risk factors in the secondary cancer group were a high incidence of coexisting adenoma and high frequency of colorectal cancer in second-degree relatives. Those in whom secondary cancer occurred were divided into two groups: the adenoma component (AC) group; and the non-adenoma component (DN) group. Secondary cancer in the DN group revealed lower grade of cell differentiation and more frequent depressed macroscopic findings than in the AC group. As a result, the prognosis of the DN group was worse than that of the AC group (p < 0.05). Based on these results, the recommended follow-up should include colonoscopy in the first years after primary cancer resection and according to the findings of the first colonoscopy the frequency of colonofiberscopic follow-up must be decided.     

Clinical experience in Hurthle cell tumors

In the period 1987-1997 6 patients with Hürthle cell carcinomas and 4 patients with Hürthle cell adenomas underwent primary surgical treatment (8.1% of all thyroid carcinomas). The diagnosis of Hürthle cell tumor was based on the presence of more then 75% Hürthle cells and the malignity on capsular or/and vascular invasion. All the patients with Hürthle cell cancer underwent total thyroidectomy, in three cases with Hürthle cell adenoma thyroid lobectomy was performed and in one case total thyroidectomy. Follow-up time ranged from 1 to 8 years after surgery (mean 4.5 years). There was no death and no recurrence. The Authors have studied the nuclear DNA content in Hürthle cell tumors: 3 adenomas were euploid and 1 was aneuploid, 4 carcinomas were aneuploid and 2 were euploid. The results in Authors' study of the DNA content and nuclear DNA ploidy are not uniformly consistent enough to allow a distinction between benign and malignant neoplasms and to evaluate the prognosis, but the number of patients and the follow up are still too limited.     

Leisure and occupational physical activity and risk of colorectal adenomatous polyps

Multiple studies have shown a protective effect for physical activity on the incidence of colorectal cancer, but few have addressed its association with incident adenomas and none have investigated its association with metachronous adenomas. We interviewed 2,001 patients undergoing colonoscopy in 3 New York City practices between 1986-1988. Of these, 298 had a first diagnosis of adenomas, 506 had normal colonoscopies, 197 had metachronous adenomas and 345 had normal colonoscopies with a past history of adenomas. Subjects were queried regarding use of moderate amounts of recreational exercise (swimming, jogging, biking, racket sports and other sports) on a regular basis, and were also asked to estimate their level of physical activity. Occupational physical activity was assessed through a blinded coding of occupational titles. After adjusting for age, years of education, body mass index, total caloric intake, dietary fiber intake, dietary fat intake and years of cigarette smoking, protective effects of borderline significance were observed among males for leisure physical activity for metachronous and incident cases. Occupational physical activity was found to be significantly protective in male incident cases. Men with increased levels of either occupational or leisure activity showed a reduction for incident and metachronous cases. No effects were observed for females. Thus, in this study, both leisure and occupational physical activity were associated with a reduced risk of incident and metachronous adenomas among men but not women.     

Population based randomized study of uptake and yield of screening by flexible sigmoidoscopy compared with screening by faecal occult blood testing

OBJECTIVES: To compare the feasibility of mass screening by flexible sigmoidoscopy with screening by faecal occult blood testing (Haemoccult) and both tests combined. DESIGN: Patients were randomised to screening by flexible sigmoidoscopy, faecal blood testing, or both tests. The flexible sigmoidoscopy examinations were performed by a general practitioner. SETTING: General practice. SUBJECTS: 3744 patients aged 50-75 years. Main outcome measures: Uptake, positive results, detection of neoplasia, complications, and recall for diagnostic colonoscopy. RESULTS: Uptake was significantly higher in the flexible sigmoidoscopy group (46.6%) than in the faecal blood test group (31.6%; P<0.001) or than in the group having both tests (30.1%; P<0.001). Telephone reminders increased uptake of sigmoidoscopy to 61.8%. In total, 1116 sigmoidoscopy examinations were performed without major complication. Polyps were found in 19. 3% (95% confidence interval 17.0% to 21.6%) but only 6.8% (5.3% to 8. 3%) had adenomas and 2.4% (1.5% to 3.3%) "high risk" adenomas. Cancer was detected in four subjects. The faecal blood test yielded positive results in 0.8% (0.2% to 1.4%) but missed at least one cancer and 30 cases of adenoma which were found by sigmoidoscopy in the combined group. Use of histological criteria-shown elsewhere to correlate with future risk of colorectal cancer-to select "positive" patients could reduce recall for diagnostic colonoscopy from about 20% to less than 5%. CONCLUSIONS: Some of the predicted obstacles to screening with flexible sigmoidoscopy are surmountable. Clear evidence relating to efficacy will be obtained only from a randomised controlled trial.     

Pleomorphic adenoma of the parotid gland. Results of surgical treatment

Twenty years experience of lateral parotidectomy as suspical treatment for pleomorphic adenoma are reviewed. All cases were managed at the ORL Clinic of the University of Zürich. 167 patients were followed for the frequency of possible recurrent tumors. Three patients (3/123) operated primarily developed a recurrences. Recurrences appeared after an average of 10 years, ranging from 1-30 years. The follow-up time varied from 1 to 21 years (average, 8 years). 39% (13 of 33) of the patients, who were re-operated for a recurrent tumor, developed another recurrence. The second recurrence appeared after an average of 10 years, ranging from 1-22 years. A persistent partial paresis of the facial nerve was found in 1% of the patients operated primarily and in 9% of the patients operated more than once. No paralysis was seen. We now choose "en-bloc" resections of pleomorphic adenomas without intra-operative opening of the tumor capsule as the treatment of choice. This treatment was possible in 83% of all cases, using a lateral parotidectomy. If tumor extends into the medial parotid lobe, total parotidectomy is required.     

Double-contrast barium enema versus colonoscopy in the diagnosis of neoplastic disorders: aspects of decision-making in general practice

A total of 190 patients, referred by general practitioners for a double-contrast barium enema, were subsequently examined with colonoscopy. With colonoscopy and histology as the reference standard, sensitivity, specificity, positive and negative predictive values, and accuracy for the radiological detection of cancer and polyps were calculated. No cancer was overlooked by the radiological examination, but there were four false positives. The overall sensitivity for polyps was 70%, increasing to 81% for polyps > or = 10 mm. The predictive value was 93-97% for the exclusion of polyps. The caecum was reached in 187 patients by double-contrast barium enema (98%) and in 164 patients (86%) by colonoscopy. Lesions in four of 12 patients who had radiological changes were undetected at the first colonoscopy, but a repeat examination showed polyps > or = 10 mm in size. Although colonoscopy is a more sensitive technique for the detection of small mucosal lesions, the general practitioners may, in the vast majority of patients, rely on a negative result for polyps and cancer obtained by the double-contrast barium enema. The latter is linked with a number of false-positive cases, while colonoscopy is associated with technical difficulties; both techniques may lead to repeated examinations, regardless of which was the first choice.     

Hidrocolonic ultrasonography in the detection of tumoral processes in the inferior gastrointestinal tract

OBJECTIVES: To determine the value of hidrocolonic ultrasound in the detection of proliferative lesions in the colon and to compare it with other techniques of already proven value. MATERIAL AND METHODS: We performed a prospective blinded trial including 155 patients (82 males and 73 females) with ages ranging from 33 to 94 years (average of 58) and clinical and analytical criteria suggesting the existence of colonic proliferative lesions. Patients with rectal mass or those with deficient bowel preparation were excluded. Ultrasound findings were compared to those obtained by colonoscopy (133 cases) and by Barium RX studies (22 cases) and all diagnoses were always confirmed by histologic exams. RESULTS: 155 patients were studied. 50 of them had cancer and 46 of these 50 were diagnosed by Hidrocolonic Ultrasound (92%); 19 had polyps > 7 mm. and 15 of these (78.9%) were diagnosed by Hidrocolonic Ultrasound. Hidrocolonic Ultrasound failed to detect all the polyps < 7 mm. The overall sensitivity, specificity, positive predictive value and negative predictive value for identifying colon carcinoma were 92%, 98%, 95.8% and 96.2% respectively and for polyps > 7 mm were 78.9%, 100%, 100% and 97.1%, respectively. The mean time for examination was 14 minutes. Tolerance was good in 114 patients (73.5%), 29 showed a slight discomfort (18.7%) and 12 (7.7%) showed a great discomfort. There were no complications. CONCLUSIONS: Hidrocolonic ultrasound is an innocuous, fast, well tolerated technique for detecting colonic proliferative lesions > 7 mm H.U. can be considered as a useful complementary technique to other more expensive and invasive ones, such as barium RX studies and Colonoscopy.