Rebecca E. Rudolph

Effect of Segment Length on Risk for Neoplastic Progression in Patients with Barrett Esophagus

In Barrett esophagus, the normal stratified squamous epithelium of the esophagus is replaced by specialized columnar epithelium in response to the tissue injury caused by chronic gastroesophageal reflux (1). Barrett esophagus is present in approximately 5% to 15% of persons with clinical indications for elective upper endoscopy (2-5). The results of several recent studies suggest that most patients with Barrett esophagus have short-segment (<3 cm) Barrett esophagus (2-7). Patients with long-segment ( 3 cm) Barrett esophagus are known to have a much greater risk for esophageal adenocarcinoma than members of the general population (8-11). Because investigators were initially uncertain whether short-segment Barrett esophagus predisposed persons to esophageal adenocarcinoma and because short-segment Barrett esophagus is more difficult to diagnose endoscopically (12), patients with short segments were often excluded from studies of the natural history of Barrett esophagus (8-11, 13, 14). Since the late 1980s, however, there have been several reports of esophageal adenocarcinoma in patients with short-segment Barrett esophagus (5, 15-18). Although this suggests that patients with short-segment Barrett esophagus are at increased risk for esophageal adenocarcinoma, the extent of the increase is largely unknown. The survival of patients who receive a diagnosis of esophageal adenocarcinoma is usually poor. More than 90% of patients with invasive disease die within 5 years of diagnosis (19). If tumors are resected at an early stage, however, survival improves substantially (20-22). Therefore, many authors have recommended regular endoscopic surveillance for patients with Barrett esophagus who are good surgical candidates (20, 21, 23-27) and prompt resection of the entire Barrett segment if cancer is identified (22, 28, 29). However, endoscopic surveillance has several disadvantages, including its high cost, procedure-related risks, inconvenience, and discomfort (30, 31). Because only a small percentage of patients with Barrett esophagus will develop cancer, it is reasonable to question the merits of frequent endoscopic surveillance for all such persons (11, 12, 23). We hypothesized that the risk for esophageal adenocarcinoma would increase with Barrett segment length. If this was true, it might be appropriate to perform endoscopic surveillance less frequently in patients with short-segment Barrett esophagus than in those with longer segments. To investigate this hypothesis, we conducted a prospective cohort study among patients who were participating in the Seattle Barretts Esophagus Project, which includes regular endoscopic surveillance. We determined the incidence of esophageal adenocarcinoma in patients with short-segment Barrett esophagus and examined the relation between segment length and cancer risk through multivariate analyses. We also examined the relation between segment length and aneuploidy, a genetic abnormality that usually precedes the development of esophageal adenocarcinoma and has been shown to predict progression to cancer (32). Aneuploidy was chosen as an outcome of interest primarily because it occurred more frequently than cancer in the study cohort, thus increasing statistical power for analyzing the relation between segment length and neoplastic progression. Methods Study Sample Study participants were selected from a cohort of patients who were enrolled in the Seattle Barretts Esophagus Project and underwent endoscopic surveillance between July 1983 and July 1998. Gastroenterologists who practice in Washington State have been the primary source of referrals to this cohort. All cohort members who met the following criteria as of 10 July 1998 were included in our study: 1) at least two endoscopies with histologic diagnoses, 2) presence of specialized columnar epithelium in the esophagus at the first endoscopy, 3) a record of Barrett segment length at the first endoscopy, 4) no esophageal cancer at the first endoscopy, and 5) no history of esophageal cancer. Three hundred nine persons qualified for the study. All of the study patients received counseling on lifestyle measures to reduce gastroesophageal reflux, and most used acid-reducing medication regularly. The Human Subjects Review Committee at the University of Washington approved the study. To evaluate the relation between segment length and aneuploidy, it was necessary to have information about the presence or absence of aneuploidy from at least two endoscopies. Of the 208 patients for whom this information was available, 37 had aneuploidy at the first qualifying endoscopy and were therefore excluded, leaving 171 for analyses with the aneuploidy end point. Endoscopy Barrett segment length was defined as the distance between the esophagogastric junction and the squamocolumnar junction. The esophagogastric junction was defined as the endoscopic lower esophageal sphincter or, if this was not apparent, the location at which the tubular esophagus joined the proximal margin of the gastric folds. The squamocolumnar junction was defined as the location at which the light-pink mucosa of the squamous-lined esophagus joined the red mucosa of the columnar-lined esophagus. The locations of these landmarks were determined as the endoscope was withdrawn from the stomach to the upper esophagus. Air was always removed from the stomach before this assessment. Tissue samples were obtained by using the turn and suction technique and jumbo biopsy forceps, as described elsewhere (33, 34). Until 1992, four biopsies (one per quadrant of the esophagus) were obtained from every other centimeter of the Barrett segment in all patients. From 1992 through 1998, four biopsies (one per quadrant of the esophagus) were obtained from every centimeter of the Barrett segment in patients with a history of high-grade dysplasia. In all patients, at least one control biopsy specimen was also taken from the gastric fundus and several biopsy specimens were taken from any visible mucosal abnormality. Each biopsy specimen was oriented on plastic mesh, epithelial surface upward, as soon as it was obtained. The gastric biopsy specimen and half of the first biopsy specimen from every level were placed in separate vials containing minimum essential medium with 5% serum and 10% dimethyl sulfoxide. The specimens were then immediately placed on wet ice and were stored at 70 C for subsequent flow cytometric analysis. The other half of the first biopsy specimen and the remaining three biopsy specimens from each level were placed in Hollande solution (one vial per level) for subsequent histologic examination. The most advanced histologic diagnosis at a given endoscopy was used to select the follow-up interval to the next endoscopy and the biopsy protocol for that endoscopy. The median interval between endoscopies was 25 months for patients with a baseline diagnosis of metaplasia, 18 months for patients with a baseline diagnosis of indefinite for dysplasia or low-grade dysplasia, and 5 months for patients with a baseline diagnosis of high-grade dysplasia. Histologic Examination The fixed biopsy specimens were serially cut into 4-m sections, mounted onto slides, and stained with hematoxylin and eosin alone or with hematoxylin and eosin, saffron, and Alcian blue at a pH of 2.5. The slides were examined by an experienced gastrointestinal pathologist, as described elsewhere (35). A histologic diagnosis of negative for dysplasia, indefinite for dysplasia, low-grade dysplasia, high-grade dysplasia, or intramucosal carcinoma was assigned to each slide by using established criteria (36). Because pathologists cannot consistently differentiate between the diagnoses of indefinite for dysplasia and low-grade dysplasia (36), these histologic diagnoses were combined into one category for all statistical analyses. DNA Content Flow Cytometry The methods used to prepare biopsy specimens for cell sorting, to perform flow cytometry, and to analyze the resulting data have been described elsewhere (34). Aneuploidy was diagnosed if, in at least one biopsy specimen from a particular endoscopy, two discrete peaks were observed on the histogram (one reflecting the presence of an aneuploid population and the other reflecting the presence of a diploid population) and the aneuploid peak represented at least 2.5% of the cells in the biopsy specimen (32). Tetraploid DNA contents in the range of 3.85N to 4.1N were also excluded. Demographic, Lifestyle, and Anthropometric Data Trained staff used a standard questionnaire to interview 71% (220 of 309) of the patients in this study in person between January 1995 and July 1998. Collected data included information on cigarette use, usual weight, height, ethnicity, annual income, education, and symptoms of gastroesophageal reflux. Information on age at study entry and sex was extracted from electronic patient records. Statistical Analysis Incidence rates were calculated by dividing the total number of cases by the total follow-up time (in person-years) in the full study sample or in defined subsets of the study sample. For each patient, follow-up time within the cohort began on the date of the first endoscopy that met the eligibility criteria. In analyses in which cancer was the outcome of interest, follow-up time ended on the date of the last endoscopy before the end of our study (10 July 1998) or on the date of the endoscopy that led to a diagnosis of cancer, whichever occurred first. Similarly, in analyses in which aneuploidy was the outcome of interest, follow-up time ended on the date of the last endoscopy before the end of the study or on the date of the endoscopy that led to a diagnosis of aneuploidy. In the analyses in which aneuploidy was the disease end point, a small number of participants (n=10) received a diagnosis of cancer at an endoscopy for which no flow cytometry data were available. Because approximately 90% of esophageal adenocarcinomas contain aneuploid cell p

Exercise Effect on Weight and Body Fat in Men and Women

Objectives: The effect of national exercise recommendations on adiposity is unknown and may differ by sex. We examined long‐term effects of aerobic exercise on adiposity in women and men.

Safety of a systematic endoscopic biopsy protocol in patients with Barrett’s esophagus

OBJECTIVE:Widespread implementation of rigorous, systematic endoscopic biopsy protocols for patients with Barretts esophagus may be hindered by concerns about their safety. This report describes the safety experience of a large series of patients with gastroesophageal reflux disease and Barretts esophagus who underwent such procedures.METHODS:Patients in the Seattle Barretts Esophagus Project undergo biopsy surveillance in a research-based clinical setting, using large channel endoscopes and “jumbo” biopsy forceps. After visual inspection, multiple biopsies are obtained from lesions and at 1- to 2-cm intervals throughout the Barretts esophageal segment.RESULTS:From 1983 to 1997, 1,458 consecutive endoscopies were performed on 705 patients and 50,833 biopsies (average, 35; maximum, 120 per procedure) were taken. Procedures lasted from 15 to 90 min during which one to two biopsies were obtained per minute. Eleven patients experienced 18 significant adverse events, five of which led to overnight hospitalizations: two for bleeding attributed to concomitant esophageal stricture dilation; two for cardiac dysrhythmias; and one for respiratory arrest. Events managed in outpatient settings included chest pain during seven endoscopies (all accounted for by two patients), chest or epigastric pain developing after five endoscopies, and one tonsillar abrasion. All patients recovered completely, and no deaths, perforations, aspiration, or esophageal stricturing resulted from the procedures.CONCLUSIONS:A rigorous, systematic endoscopic biopsy protocol in patients with Barretts esophagus does not produce esophageal perforation or bleeding when performed by an experienced team of physicians, nurses, and technicians.

Risk Factors for Colorectal Cancer in Relation to Number and Size of Aberrant Crypt Foci in Humans

Several characteristics of aberrant crypt foci (ACF) suggest that they are precursors of colorectal cancer, but the factors that promote or inhibit their growth are largely unknown. We conducted a pilot study to explore whether factors associated with risk of colorectal cancer are also associated with number or size of rectal ACF. Thirty-two U.S. veterans, ages 50 to 80 years, were recruited to undergo magnifying chromoendoscopy for imaging of rectal ACF and colonoscopy for identification of polyps or cancer. Participants completed a questionnaire on cigarette smoking, use of nonsteroidal anti-inflammatory drugs (NSAIDs), and family history of colorectal cancer. Fishers exact test was used to assess the statistical significance of associations between colorectal cancer risk factors and characteristics of ACF. Cochran-Mantel-Haenszel statistics and polytomous regression were used to test the significance of associations adjusted for age. Participants with a history of adenoma had more ACF than those without (age-adjusted P = 0.02), but the numbers in the two groups overlapped markedly. Older participants had more (P = 0.06) and larger (P = 0.009) ACF than younger participants. No associations were identified between either ACF number or size and cigarette smoking, use of NSAIDs, or family history of colorectal cancer. These findings suggest that persons with adenomas have somewhat more rectal ACF than persons without, and that older age is a risk factor for ACF growth. Future research should be directed toward developing techniques to identify ACF that are likely to progress to cancer and the modifiable factors that promote or inhibit such progression.

No Reduction in C-Reactive Protein following a 12-Month Randomized Controlled Trial of Exercise in Men and Women

Low-grade systemic inflammation is suggested to play a role in the development of several chronic diseases including cancer. Higher levels of physical activity and lower adiposity have been associated with reduced levels of markers of systemic inflammation, such as C-reactive protein (CRP); however, reductions in CRP have not been consistently observed in randomized controlled trials of exercise. Purpose: To examine the effect of a 12-month aerobic exercise intervention on CRP levels in men and women. Methods: One hundred two men and 100 women, sedentary and of ages 40 to 75 years, with mean body mass index (BMI) of 29.9 and 28.7 kg/m2, respectively, were randomly assigned to a 12-month moderate-to-vigorous aerobic exercise intervention (6 d/wk, 60 min/d, 60-85% maximum heart rate) or control group. Fasting blood samples were collected at baseline and at 12 months. CRP levels were measured by high-sensitivity latex-enhanced nephelometry. Results: At baseline, CRP was 1.16 and 2.11 mg/L for men and women, respectively, and CRP was correlated with percent body fat (r = 0.48, P ≤0.001), BMI (r = 0.37, P ≤ 0.001), and aerobic fitness (r = −0.49, P ≤ 0.001). No intervention effects were observed for CRP in men or women, or when stratified by baseline BMI (<30 versus ≥30 kg/m2), baseline CRP (<3 versus ≥3 mg/L), or change in body weight, body composition, or aerobic fitness. Conclusion: A 12-month moderate-to-vigorous aerobic exercise intervention did not affect CRP levels in previously sedentary men or women with average-risk CRP values at baseline. (Cancer Epidemiol Biomarkers Prev 2008;17(7):1714–8)

No Effect of Exercise on Insulin-Like Growth Factor 1 and Insulin-Like Growth Factor Binding Protein 3 in Postmenopausal Women: a 12-Month Randomized Clinical Trial

A meta-analysis indicated that increased circulating concentrations of insulin-like growth factor 1 (IGF-1) are associated with increased risks for colorectal, prostate, and premenopausal breast cancers, and that increased concentrations of IGF binding protein 3 (IGFBP-3) are associated with

Effect of a 12-Month Exercise Intervention on Patterns of Cellular Proliferation in Colonic Crypts: A Randomized Controlled Trial

Background: Colon crypt architecture and proliferation may be appropriate biomarkers for testing prevention interventions. A hypothesized mechanism for exercise-induced colon cancer risk reduction might be through alterations in colon crypt cell architecture and proliferation. Methods: Healthy, sedentary participants with a colonoscopy within the previous 3 years were recruited through gastroenterology practices and media. We randomly assigned 100 women and 102 men, ages 40 to 75 years, to a control group or a 12-month exercise intervention of moderate-to-vigorous aerobic exercise, 60 minutes per day, 6 days per week, and assessed change in number and relative position of Ki67-stained cells in colon mucosal crypts. Results: Exercisers did a mean 370 min/wk (men) and 295 min/wk (women) of exercise (seven dropped the intervention). In men, the mean height of Ki67-positive nuclei relative to total crypt height was related to amount of exercise, with changes from baseline of 0.0% (controls), +0.3% (exercisers <250 min/wk), −1.7% (exercisers 250-300 min/wk), and −2.4% (exercisers >300 min/wk; Ptrend = 0.03). In male exercisers whose cardiopulmonary fitness (VO2max) increased >5%, the mean height of Ki67-positive nuclei decreased by 2% versus 0.9% in other exercisers, and versus no change in controls (Ptrend = 0.05). Similar trends were observed in other proliferation markers. In women, increased amount of exercise or VO2max did not result in notable changes in proliferation markers. Conclusions: A 12-month moderate-to-vigorous intensity aerobic exercise intervention resulted in significant decreases in colon crypt cell proliferation indices in men who exercised a mean of ≥250 min/wk or whose VO2max increased by ≥5%. (Cancer Epidemiol Biomarkers Prev 2006;15(9):1588–97)

Randomized trial of exercise in sedentary middle aged women: effects on quality of life

Increasing physical activity is currently considered to be a possible prevention strategy for cancer, obesity, and cardiovascular disease, either alone or in combination with dietary changes. This paper presents results of a randomized trial of moderate-to-vigorous intensity exercise in middle aged, sedentary women; specifically, we report changes in and correlates of quality of life and functional status of this exercise intervention program for both the short (three months) and longer term (12 months). The intervention group showed a significant increase in Mental Health score from baseline to 3 months (p < .01), significantly greater than the change in the control group at 3 months (p < .01). A similar trend among exercisers was observed for the General Health score (p < .01), and this finding was significantly greater than the change in control group at 3 months (p = .01). Change in Social Support – Affection were predictors of the changes in quality of life variables. This study documented improvements in quality of life and general functioning that occurred as a result of participating in an exercise intervention in sedentary middle-aged women.

Effect of a 12-month exercise intervention on the apoptotic regulating proteins Bax and Bcl-2 in colon crypts: a randomized controlled trial.

Background: Cellular proliferation and apoptosis (cell death) are highly regulated in the colon as insufficient apoptosis may lead to polyps and cancer. Physical activity decreases risk of colon cancer in observational studies, but the biological basis is not well defined. The objective of this study is to examine the effects of a 12-month aerobic exercise program on expression of proteins that promote (Bax) or inhibit (Bcl-2) apoptosis in colon crypts. Methods: Two hundred two sedentary participants, 40 to 75 years, were randomly assigned to moderate-to-vigorous intensity exercise for 60 min per day, 6 days per week for 12 months, or usual lifestyle. Colon crypt samples were obtained at baseline and 12 months. Bcl-2 and Bax expression was measured by immunohistochemistry. Results: Bax density at the bottom of crypts increased in male exercisers versus controls (+0.87 versus −0.18; P = 0.05), whereas the ratio of Bcl-2 to Bax at the bottom and middle of crypts decreased as aerobic fitness (VO2max) increased (P trend = 0.02 and 0.05, respectively). In female exercisers, Bax density in the middle of crypts decreased (−0.36 versus +0.69; P = 0.03) and Bcl-2 to Bax ratio at the top of crypts increased versus controls (+0.46 versus −0.85; P = 0.03). Bax density in the middle of crypts also decreased as minutes per week of exercise increased (P trend = 0.03). Conclusions: A 12-month exercise intervention resulted in greater expression of proteins that promote apoptosis at the bottom of colon crypts in men and decreased expression of proteins that promote apoptosis at the middle and top of colon crypts in women. The difference in effect by gender and location of observed changes warrants further study. (Cancer Epidemiol Biomarkers Prev 2007;16(9):1767–74)

No Effect of Exercise on Colon Mucosal Prostaglandin Concentrations: A 12-Month Randomized Controlled Trial

Background: Epidemiologic studies provide evidence that exercise is associated with reduced risk of colon cancer. Exercise may exert protective effects on the colon by influencing prostaglandin production. We hypothesized that an exercise intervention would decrease prostaglandin E2 concentrations and increase prostaglandin F2α in colon biopsies compared with controls. Methods: A 12-month randomized controlled trial testing the effects of exercise on colon mucosal prostaglandin concentrations was conducted in men (n = 95) and women (n = 89). The exercise intervention included moderate-to-vigorous aerobic activity, 60 min/d, 6 days/wk versus controls. Prostaglandin E2 and F2α concentrations were measured in colon biopsies using an enzyme-linked immunoassay at baseline and at 12 months to assess changes in mean concentration for each group. Results: Baseline colon prostaglandin E2 and F2α concentrations were not correlated with age, race, education, family history of colon cancer, previous polyps, body size, diet, smoking, nonsteroidal antiinflammatory drug use, metabolic factors, or sex hormone levels. For both men and women, the exercise and control groups showed no change in mean prostaglandin E2 or F2α between the baseline and 12-month biopsies. There was no difference in mean prostaglandin concentrations between exercisers and controls when exercisers were grouped by level of intervention adherence. Results were not modified by baseline age, body mass index, percentage of body fat, nonsteroidal antiinflammatory drug use, history of adenomatous polyps, or family history of colon cancer. Conclusion: A 12-month moderate-to-vigorous intensity aerobic exercise intervention did not result in significant changes in colon mucosal prostaglandin concentrations. (Cancer Epidemiol Biomarkers Prev 2007;16(11):2351–6)