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Dive into the research topics where E. Robert Greenberg is active.

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Featured researches published by E. Robert Greenberg.


The New England Journal of Medicine | 1994

A clinical trial of antioxidant vitamins to prevent colorectal adenoma

E. Robert Greenberg; John A. Baron; Tor D. Tosteson; Daniel H. Freeman; Gerald J. Beck; John H. Bond; Thomas A. Colacchio; John A. Coller; Harold D. Frankl; Robert W. Haile; Jack S. Mandel; David W. Nierenberg; Richard I. Rothstein; Dale C. Snover; Marguerite Stevens; Robert W. Summers; Rosalind U. van Stolk

BACKGROUND People who consume a diet high in vegetables and fruits have a lower risk of cancer of the large bowel. Antioxidant vitamins, which are present in vegetables and fruits, have been associated with a diminished risk of cancers at various anatomical sites. We conducted a randomized, controlled clinical trial to test the efficacy of beta carotene and vitamins C and E in preventing colorectal adenoma, a precursor of invasive cancer. METHODS We randomly assigned 864 patients, using a two-by-two factorial design, to four treatment groups, which received placebo; beta carotene (25 mg daily); vitamin C (1 g daily) and vitamin E (400 mg daily); or the beta carotene plus vitamins C and E. In order to identify new adenomas, we performed complete colonoscopic examinations in the patients one year and four years after they entered the study. The primary end points for analyses were new adenomas identified after the first of these two follow-up examinations. RESULTS Patients adhered well to the prescribed regimen, and 751 completed the four-year clinical trial. There was no evidence that either beta carotene or vitamins C and E reduced the incidence of adenomas; the relative risk for beta carotene was 1.01 (95 percent confidence interval, 0.85 to 1.20); for vitamins C and E, it was 1.08 (95 percent confidence interval, 0.91 to 1.29). Neither treatment appeared to be effective in any subgroup of patients or in the prevention of any subtype of polyp defined by size or location. CONCLUSIONS The lack of efficacy of these vitamins argues against the use of supplemental beta carotene and vitamins C and E to prevent colorectal cancer. Although our data do not prove definitively that these antioxidants have no anticancer effect, other dietary factors may make more important contributions to the reduction in the risk of cancer associated with a diet high in vegetables and fruits.


Journal of Clinical Oncology | 2002

Neuropsychologic Impact of Standard-Dose Systemic Chemotherapy in Long-Term Survivors of Breast Cancer and Lymphoma

Tim A. Ahles; Andrew J. Saykin; Charlotte T. Furstenberg; Bernard F. Cole; Leila A. Mott; Karen Skalla; Marie B. Whedon; Sarah Bivens; Tara Mitchell; E. Robert Greenberg; Peter M. Silberfarb

PURPOSE The primary purpose of this study was to compare the neuropsychologic functioning of long-term survivors of breast cancer and lymphoma who had been treated with standard-dose systemic chemotherapy or local therapy only. PATIENTS AND METHODS Long-term survivors (5 years postdiagnosis, not presently receiving cancer treatment, and disease-free) of breast cancer or lymphoma who had been treated with systemic chemotherapy (breast cancer: n = 35, age, 59.1 +/- 10.7 years; lymphoma: n = 36, age, 55.9 +/- 12.1 years) or local therapy only (breast cancer: n = 35, age, 60.6 +/- 10.5 years; lymphoma: n = 22, age, 48.7 +/- 11.7 years) completed a battery of neuropsychologic and psychologic tests (Center for Epidemiological Study-Depression, Spielberger State-Trait Anxiety Inventory, and Fatigue Symptom Inventory). RESULTS Multivariate analysis of variance, controlling for age and education, revealed that survivors who had been treated with systemic chemotherapy scored significantly lower on the battery of neuropsychologic tests compared with those treated with local therapy only (P <.04), particularly in the domains of verbal memory (P <.01) and psychomotor functioning (P <.03). Survivors treated with systemic chemotherapy were also more likely to score in the lower quartile on the Neuropsychological Performance Index (39% v 14%, P <.01) and to self-report greater problems with working memory on the Squire Memory Self-Rating Questionnaire (P <.02). CONCLUSION Data from this study support the hypothesis that systemic chemotherapy can have a negative impact on cognitive functioning as measured by standardized neuropsychologic tests and self-report of memory changes. However, analysis of the Neuropsychological Performance Index suggests that only a subgroup of survivors may experience long-term cognitive deficits associated with systemic chemotherapy.


The New England Journal of Medicine | 1990

A clinical trial of beta carotene to prevent basal-cell and squamous-cell cancers of the skin

E. Robert Greenberg; John A. Baron; Therese A. Stukel; Marguerite Stevens; Jack S. Mandel; Steven K. Spencer; Peter M. Elias; Nicholas J. Lowe; David W. Nierenberg; Garrett Bayrd; J. Corwin Vance; Daniel H. Freeman; William E. Clendenning; Theodore H. Kwan

BACKGROUND Beta carotene has been associated with a decreased risk of human cancer in many studies employing dietary questionnaires or blood measurements, and it has had protective effects in some animal models of carcinogenesis. METHODS We tested the possible cancer-preventing effects of beta carotene by randomly assigning 1805 patients who had had a recent nonmelanoma skin cancer to receive either 50 mg of beta carotene or placebo per day and by conducting annual skin examinations to determine the occurrence of new nonmelanoma skin cancer. RESULTS Adherence to the prescribed treatment was good, and after one year the actively treated groups median plasma beta carotene level (3021 nmol per liter) was much higher than that of the control group (354 nmol per liter). After five years of follow-up, however, there was no difference between the groups in the rate of occurrence of the first new nonmelanoma skin cancer (relative rate, 1.05; 95 percent confidence interval, 0.91 to 1.22). In subgroup analyses, active treatment showed no efficacy either in the patients whose initial plasma beta carotene level was in the lowest quartile or in those who currently smoked. There was also no significant difference between treated and control groups in the mean number of new nonmelanoma skin cancers per patient-year. CONCLUSIONS In persons with a previous nonmelanoma skin cancer, treatment with beta carotene does not reduce the occurrence of new skin cancers over a five-year period of treatment and observation.


Gastroenterology | 2009

A Pooled Analysis of Advanced Colorectal Neoplasia Diagnoses After Colonoscopic Polypectomy

Maria Elena Martinez; John A. Baron; David A. Lieberman; Arthur Schatzkin; Elaine Lanza; Sidney J. Winawer; Ann G. Zauber; Ruiyun Jiang; Dennis J. Ahnen; John H. Bond; Timothy R. Church; Douglas J. Robertson; Stephanie A. Smith-Warner; Elizabeth T. Jacobs; David S. Alberts; E. Robert Greenberg

BACKGROUND & AIMS Limited data exist regarding the actual risk of developing advanced adenomas and cancer after polypectomy or the factors that determine risk. METHODS We pooled individual data from 8 prospective studies comprising 9167 men and women aged 22 to 80 with previously resected colorectal adenomas to quantify their risk of developing subsequent advanced adenoma or cancer as well as identify factors associated with the development of advanced colorectal neoplasms during surveillance. RESULTS During a median follow-up period of 47.2 months, advanced colorectal neoplasia was diagnosed in 1082 (11.8%) of the patients, 58 of whom (0.6%) had invasive cancer. Risk of a metachronous advanced adenoma was higher among patients with 5 or more baseline adenomas (24.1%; standard error, 2.2) and those with an adenoma 20 mm in size or greater (19.3%; standard error, 1.5). Risk factor patterns were similar for advanced adenomas and invasive cancer. In multivariate analyses, older age (P < .0001 for trend) and male sex (odds ratio [OR], 1.40; 95% confidence interval [CI], 1.19-1.65) were associated significantly with an increased risk for metachronous advanced neoplasia, as were the number and size of prior adenomas (P < .0001 for trend), the presence of villous features (OR, 1.28; 95% CI, 1.07-1.52), and proximal location (OR, 1.68; 95% CI, 1.43-1.98). High-grade dysplasia was not associated independently with metachronous advanced neoplasia after adjustment for other adenoma characteristics. CONCLUSIONS Occurrence of advanced colorectal neoplasia is common after polypectomy. Factors that are associated most strongly with risk of advanced neoplasia are patient age and the number and size of prior adenomas.


International Journal of Cancer | 1999

Increase in incidence rates of basal cell and squamous cell skin cancer in New Hampshire, USA

Margaret R. Karagas; E. Robert Greenberg; Steven K. Spencer; Therese A. Stukel; Leila A. Mott

We conducted a study to estimate the current incidence rates of basal‐cell carcinoma (BCC) and squamous‐cell carcinoma (SCC) of the skin in the population of New Hampshire (NH), USA, and to quantify recent changes in the incidence rates of these malignancies. BCCs and SCCs diagnosed among NH residents were identified through physician practices and central pathology laboratories in NH and bordering regions from June 1979 through May 1980 and from July 1993 through June 1994. For each diagnosis period, we estimated the age‐adjusted incidence rates for both BCC and SCC among both men and women and for separate anatomic sites. Between 1979–1980 and 1993–1994, incidence rates of SCC increased by 235% in men and by 350% in women. Incidence rates of BCC increased by more than 80% in both men and women. While the absolute increase was greatest for tumors of the head and neck, the relative change was most pronounced for tumors on the trunk in men and on the lower limb in women. Thus, there has been a marked rise in the incidence rates of BCC and SCC skin cancers in NH in recent years. The anatomic pattern of increase in BCC and SCC incidence is consistent with an effect of greater sunlight exposure. Studies of BCC and SCC occurrence are needed to identify possible behavioral and environmental factors and to assess possible changes in diagnostic practices that might account for the rise in incidence of these common malignancies. Int. J. Cancer 81:555–559, 1999.


The Lancet | 1998

Over-the-counter analgesics and risk of ovarian cancer

Daniel W. Cramer; Bernard L. Harlow; Linda Titus-Ernstoff; Kari Bohlke; William R. Welch; E. Robert Greenberg

BACKGROUND Evidence that aspirin and other non-steroidal anti-inflammatory drugs reduce risk for colorectal cancer has prompted interest in their ability to prevent other cancers. We aimed to find out what effect over-the-counter analgesics have on risk of ovarian cancer. METHODS In a case-control study we compared use of over-the-counter analgesics by 563 women from eastern Massachusetts and New Hampshire, USA, who had epithelial ovarian cancer with 523 women from the general population. We calculated exposure odds ratios to estimate the effect of over-the-counter analgesics on ovarian cancer risk. Use of over-the-counter analgesics was assessed through interviews and defined as use at least once a week continuously for at least 6 months. FINDINGS The odds ratio for risk of ovarian cancer for aspirin use was 0.75 (95% CI 0.52-1.10), that for ibuprofen was 1.03 (0.64-1.64), and that for paracetamol was 0.52 (0.31-0.86), after adjusting for age, study centre, education, religion, parity, oral contraceptive use, and menstrual, arthritic, or headache pain. Relative to no use, the lower risk of ovarian cancer associated with paracetamol was more apparent for use on a daily basis, 0.39 (0.21-0.74), for more than 10 years of use, 0.40 (0.19-0.88), or for more than 20 tablet years defined as (tablets per day x years of use), 0.45 (0.20-0.99). INTERPRETATION In our data, there was a statistically significant inverse association between paracetamol use and ovarian cancer risk. There was a modest but non-significant inverse association with aspirin use and ovarian cancer and no association with ibuprofen use. Experimental studies in rodents demonstrating uterine and ovarian atrophy at high doses of paracetamol and decreased ovarian-cyst formation at lower doses suggest a biological basis for our observations.


The Lancet | 2011

14-day triple, 5-day concomitant, and 10-day sequential therapies for Helicobacter pylori infection in seven Latin American sites: a randomised trial

E. Robert Greenberg; Garnet L. Anderson; Douglas R. Morgan; Javier Torres; William D. Chey; Luis Eduardo Bravo; Ricardo L. Dominguez; Catterina Ferreccio; Rolando Herrero; Eduardo Lazcano-Ponce; Maria Mercedes Meza-Montenegro; Rodolfo Peña; Edgar M. Peña; Eduardo Salazar-Martínez; Pelayo Correa; Maria Elena Martinez; Manuel Valdivieso; Gary E. Goodman; John Crowley; Laurence H. Baker

BACKGROUND Evidence from Europe, Asia, and North America suggests that standard three-drug regimens of a proton-pump inhibitor plus amoxicillin and clarithromycin are significantly less effective for eradication of Helicobacter pylori infection than are 5-day concomitant and 10-day sequential four-drug regimens that include a nitroimidazole. These four-drug regimens also entail fewer antibiotic doses than do three-drug regimens and thus could be suitable for eradication programmes in low-resource settings. Few studies in Latin America have been done, where the burden of H pylori-associated diseases is high. We therefore did a randomised trial in Latin America comparing the effectiveness of four-drug regimens given concomitantly or sequentially with that of a standard 14-day regimen of triple therapy. METHODS Between September, 2009, and June, 2010, we did a randomised trial of empiric 14-day triple, 5-day concomitant, and 10-day sequential therapies for H pylori in seven Latin American sites: Chile, Colombia, Costa Rica, Honduras, Nicaragua, and Mexico (two sites). Participants aged 21-65 years who tested positive for H pylori by a urea breath test were randomly assigned by a central computer using a dynamic balancing procedure to: 14 days of lansoprazole, amoxicillin, and clarithromycin (standard therapy); 5 days of lansoprazole, amoxicillin, clarithromycin, and metronidazole (concomitant therapy); or 5 days of lansoprazole and amoxicillin followed by 5 days of lansoprazole, clarithromycin, and metronidazole (sequential therapy). Eradication was assessed by urea breath test 6-8 weeks after randomisation. The trial was not masked. Our primary outcome was probablity of H pylori eradication. Our analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, registration number NCT01061437. FINDINGS 1463 participants aged 21-65 years were randomly allocated a treatment: 488 were treated with 14-day standard therapy, 489 with 5-day concomitant therapy, and 486 with 10-day sequential therapy. The probability of eradication with standard therapy was 82·2% (401 of 488), which was 8·6% higher (95% adjusted CI 2·6-14·5) than with concomitant therapy (73·6% [360 of 489]) and 5·6% higher (-0·04% to 11·6) than with sequential therapy (76·5% [372 of 486]). Neither four-drug regimen was significantly better than standard triple therapy in any of the seven sites. INTERPRETATION Standard 14-day triple-drug therapy is preferable to 5-day concomitant or 10-day sequential four-drug regimens as empiric therapy for H pylori infection in diverse Latin American populations. FUNDING Bill & Melinda Gates Foundation, US National Institutes of Health.


Gut | 2014

Colorectal cancers soon after colonoscopy: a pooled multicohort analysis

Douglas J. Robertson; David A. Lieberman; Sidney J. Winawer; Dennis J. Ahnen; John A. Baron; Arthur Schatzkin; Amanda J. Cross; Ann G. Zauber; Timothy R. Church; Peter Lance; E. Robert Greenberg; Maria Elena Martinez

Objective Some individuals are diagnosed with colorectal cancer (CRC) despite recent colonoscopy. We examined individuals under colonoscopic surveillance for colonic adenomas to assess possible reasons for diagnosing cancer after a recent colonoscopy with complete removal of any identified polyps. Design Primary data were pooled from eight large (>800 patients) North American studies in which participants with adenoma(s) had a baseline colonoscopy (with intent to remove all visualised lesions) and were followed with subsequent colonoscopy. We used an algorithm based on the time from previous colonoscopy and the presence, size and histology of adenomas detected at prior exam to assign interval cancers as likely being new, missed, incompletely resected (while previously an adenoma) or due to failed biopsy detection. Results 9167 participants (mean age 62) were included in the analyses, with a median follow-up of 47.2 months. Invasive cancer was diagnosed in 58 patients (0.6%) during follow-up (1.71 per 1000 person-years follow-up). Most cancers (78%) were early stage (I or II); however, 9 (16%) resulted in death from CRC. We classified 30 cancers (52%) as probable missed lesions, 11 (19%) as possibly related to incomplete resection of an earlier, non-invasive lesion and 14 (24%) as probable new lesions. The cancer diagnosis may have been delayed in three cases (5%) because of failed biopsy detection. Conclusions Despite recent colonoscopy with intent to remove all neoplasia, CRC will occasionally be diagnosed. These cancers primarily seem to represent lesions that were missed or incompletely removed at the prior colonoscopy and might be avoided by increased emphasis on identifying and completely removing all neoplastic lesions at colonoscopy.


Nutrition and Cancer | 1997

Feasibility of a randomized trial of a high-vegetable diet to prevent breast cancer recurrence.

John P. Pierce; Susan Faerber; Fred A. Wright; Vicky A. Newman; Shirley W. Flatt; Sheila Kealey; Cheryl L. Rock; William Hryniuk; E. Robert Greenberg

Epidemiologic evidence supports the concept that diet influences risk for breast cancer and suggests that prognosis after the diagnosis of breast cancer may also be related to modifiable nutritional factors. The purpose of this study was to investigate the feasibility of a randomized trial of a high-vegetable, reduced-fat, and increased-fiber diet intervention to reduce risk for recurrence among breast cancer survivors. This major change in dietary pattern was promoted through intensive telephone counseling. Participants were 93 women who had been diagnosed with breast cancer (stages I, II, and IIIA) within the previous four years and who had completed their initial treatment. We assessed adherence to the study diet using repeated 24-hour dietary recalls at 6 and 12 months and measurement of circulating carotenoid concentrations. Six months after randomization, the intervention group had significantly increased their mean intake of vegetables (+4.6 servings/day), fruit (+0.7 servings/day), and fiber (+6.4 g/1,000 kcal) and significantly reduced their intake of dietary fat (-9.9% of energy) compared with the control group. Circulating concentrations of carotenoids also increased in the intervention group. These changes persisted at the 12-month visit. Results of this study demonstrate that telephone counseling can be a useful approach in diet intervention and that breast cancer survivors can adopt and maintain a high-vegetable, reduced-fat dietary pattern.


Cancer Causes & Control | 1995

Strenuous physical activity in young adulthood and risk of breast cancer (United States).

Robert Mittendorf; Matthew P. Longnecker; Polly A. Newcomb; Amy Trentham Dietz; E. Robert Greenberg; Gregory F. Bogdan; Richard W. Clapp; Walter C. Willett

The epidemiologic data on the relation between strenuous physical activity and breast cancer are limited and inconsistent. Because risk of breast cancer may be influenced by ovarian function which, in turn, is modulated by physical activity, the hypothesis that exercise may be associated with a reduced risk of breast cancer merits further investigation. We, therefore, conducted a large case-control study in 1988–91, and interviewed 6,888 women (17 to 74 years of age) with breast cancer in Maine, Massachusetts, New Hampshire, and Wisconsin (United States). Interviewed controls (9,539 women, 18 to 74 years of age) were selected randomly from lists of licensed drivers (for younger women) or from a roster of Medicare enrollees (for older women). We used multivariate adjusted odds ratios (OR) and 95 percent confidence intervals (CI) from logistic regression models to estimate relative risks between self-reported physical activity when 14 to 22 years of age and breast cancer. When compared with sedentary controls, women who reported any strenuous physical activity during ages 14 to 22 years had a modest reduction in the risk of breast cancer (OR=0.95, CI=0.93–0.97). However, those who exercised vigorously at least once a day had a 50 percent reduction in risk of breast cancer (OR=0.5, CI=0.4–0.7). These data support the hypothesis that women who are physically active have a reduced risk of breast cancer.

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John A. Baron

University of North Carolina at Chapel Hill

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Dennis J. Ahnen

University of Colorado Denver

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Robert S. Sandler

University of North Carolina at Chapel Hill

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Polly A. Newcomb

Fred Hutchinson Cancer Research Center

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