Chiranjeev Dash

Screening and surveillance for the early detection of colorectal cancer and adenomatous polyps, 2008: a joint guideline from the American Cancer Society, the US Multi-Society Task Force on Colorectal Cancer, and the American College of Radiology.

In the United States, colorectal cancer (CRC) is the third most common cancer diagnosed among men and women and the second leading cause of death from cancer. CRC largely can be prevented by the detection and removal of adenomatous polyps, and survival is significantly better when CRC is diagnosed while still localized. In 2006 to 2007, the American Cancer Society, the US Multi-Society Task Force on Colorectal Cancer, and the American College of Radiology came together to develop consensus guidelines for the detection of adenomatous polyps and CRC in asymptomatic average-risk adults. In this update of each organizations guidelines, screening tests are grouped into those that primarily detect cancer early and those that can detect cancer early and also can detect adenomatous polyps, thus providing a greater potential for prevention through polypectomy. When possible, clinicians should make patients aware of the full range of screening options, but at a minimum they should be prepared to offer patients a choice between a screening test that primarily is effective at early cancer detection and a screening test that is effective at both early cancer detection and cancer prevention through the detection and removal of polyps. It is the strong opinion of these 3 organizations that colon cancer prevention should be the primary goal of screening.

Screening and Surveillance for the Early Detection of Colorectal Cancer and Adenomatous Polyps, 2008: A Joint Guideline from the American Cancer Society, the US Multi‐Society Task Force on Colorectal Cancer, and the American College of Radiology*†

In the United States, colorectal cancer (CRC) is the third most common cancer diagnosed among men and women and the second leading cause of death from cancer. CRC largely can be prevented by the detection and removal of adenomatous polyps, and survival is significantly better when CRC is diagnosed while still localized. In 2006 to 2007, the American Cancer Society, the US Multi Society Task Force on Colorectal Cancer, and the American College of Radiology came together to develop consensus guidelines for the detection of adenomatous polyps and CRC in asymptomatic average‐risk adults. In this update of each organizations guidelines, screening tests are grouped into those that primarily detect cancer early and those that can detect cancer early and also can detect adenomatous polyps, thus providing a greater potential for prevention through polypectomy. When possible, clinicians should make patients aware of the full range of screening options, but at a minimum they should be prepared to offer patients a choice between a screening test that is effective at both early cancer detection and cancer prevention through the detection and removal of polyps and a screening test that primarily is effective at early cancer detection. It is the strong opinion of these 3 organizations that colon cancer prevention should be the primary goal of screening.

American Cancer Society Guideline for the Early Detection of Prostate Cancer: Update 2010

In 2009, the American Cancer Society (ACS) Prostate Cancer Advisory Committee began the process of a complete update of recommendations for early prostate cancer detection. A series of systematic evidence reviews was conducted focusing on evidence related to the early detection of prostate cancer, test performance, harms of therapy for localized prostate cancer, and shared and informed decision making in prostate cancer screening. The results of the systematic reviews were evaluated by the ACS Prostate Cancer Advisory Committee, and deliberations about the evidence occurred at committee meetings and during conference calls. On the basis of the evidence and a consensus process, the Prostate Cancer Advisory Committee developed the guideline, and a writing committee drafted a guideline document that was circulated to the entire committee for review and revision. The document was then circulated to peer reviewers for feedback, and finally to the ACS Mission Outcomes Committee and the ACS Board of Directors for approval. The ACS recommends that asymptomatic men who have at least a 10‐year life expectancy have an opportunity to make an informed decision with their health care provider about screening for prostate cancer after they receive information about the uncertainties, risks, and potential benefits associated with prostate cancer screening. Prostate cancer screening should not occur without an informed decision‐making process. Men at average risk should receive this information beginning at age 50 years. Men in higher risk groups should receive this information before age 50 years. Men should either receive this information directly from their health care providers or be referred to reliable and culturally appropriate sources. Patient decision aids are helpful in preparing men to make a decision whether to be tested. CA Cancer J Clin 2010;60:70–98.

Colorectal cancer screening barriers and facilitators in older persons

BACKGROUNDnThis systematic review identifies factors that are most consistently mentioned as either barriers to or facilitators of colorectal cancer (CRC) screening in older persons.nnnMETHODSnA systematic literature search (1995-2008) was conducted to identify studies that reported barriers to or facilitators of CRC screening uptake, compliance or adherence specifically for older persons (> or = 65 years). Information on study characteristics and barriers and facilitators related to subjects; healthcare providers; policies; and screening tests were then abstracted and analyzed.nnnRESULTSnEighty-three studies met the eligibility criteria. Low level of education, African American race, Hispanic ethnicity, and female gender were the most frequently reported barriers, whereas being married or living with a partner was the most frequently reported facilitator. The most cited barrier related to healthcare providers was lack of screening recommendation by a physician; having a usual source of care was a commonly reported facilitator. Lack of health insurance, and dual coverage with Medicare and Medicaid were the most frequently reported barriers, whereas Medicares coverage of screening colonoscopy was consistently reported as a facilitator.nnnCONCLUSIONSnBarriers to, and facilitators of, CRC screening among older persons are reported. Particular attention should be paid to modifiable factors that could become the focus of interventions aimed at increasing CRC screening participation in older persons.

Effects of Vitamin D and Calcium Supplementation on Markers of Apoptosis in Normal Colon Mucosa: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

To further clarify and/or develop calcium and vitamin D as chemopreventive agents against colorectal cancer in humans, understand the mechanisms by which these agents reduce risk for the disease, and develop “treatable” biomarkers of risk for colorectal cancer, we conducted a pilot, randomized, double-blind, placebo-controlled, 2 × 2 factorial clinical trial to test the effects of calcium and vitamin D3, alone and in combination on markers of apoptosis, in the normal colorectal mucosa. Ninety-two men and women with at least one pathology-confirmed colorectal adenoma were treated with 2.0 g/d calcium or 800 IU/d vitamin D3, alone or in combination, versus placebo over 6 months. Overall expression and colorectal crypt distributions of Bcl-2 (an apoptosis inhibitor) and Bax (an apoptosis promoter) in biopsies of normal-appearing rectal mucosa were detected by automated immunohistochemistry and quantified by image analysis. After 6 months of treatment, Bax expression along the full lengths of crypts increased 56% (P = 0.02) in the vitamin D group and 33% in both the calcium (P = 0.31) and calcium plus vitamin D (P = 0.36) groups relative to the placebo group. The vitamin D treatment effect was more pronounced in the upper 40%, or differentiation zone, of crypts (80%; P = 0.01). There were no statistically significant treatment effects on Bcl-2 expression. Overall, these preliminary results suggest that calcium and vitamin D, individually or together, may enhance apoptosis in the normal human colorectal epithelium, and the strongest treatment effects may be vitamin D related and in the upper sections of the colorectal crypts.

A summary measure of pro- and anti-oxidant exposures and risk of incident, sporadic, colorectal adenomas

Despite compelling basic science evidence, the search for causal associations linking specific pro- and anti-oxidants to presumably oxidative stress-related neoplasms, such as colorectal adenoma, has produced inconsistent results. We developed an oxidative balance score (OBS) to characterize the pro-oxidant and anti-oxidant exposures of 2,305 participants in a case–control study of colorectal adenoma that used both endoscopy-confirmed and community controls. Twelve lifestyle medical and dietary factors with known pro- or anti-oxidant properties were considered. Each high anti-oxidant exposure and low pro-oxidant exposure was awarded one or two points depending on the level of exposure, and the points for each OBS component were summed. We observed a significant inverse association between OBS (continuous variable) and colorectal adenoma in the analyses with either community, or endoscopy controls (each p-trendxa0<xa00.01). When the OBS was treated as an ordinal variable and a score of ≤3xa0points was used as the referent category, in the analyses with the endoscopy controls the adjusted odds ratios for scores of 4–6, 7–9, 10–12, 13–15, and 16+, were 0.42, 0.32, 0.22, 0.20, and 0.19, respectively, with all 95% confidence intervals excluding 1.0. The corresponding analysis for community controls showed a similar trend. Our findings are in line with the basic science evidence supporting the role of oxidative stress in colorectal neoplasia.

Urinary Bladder Cancer Risk Factors in Egypt: A Multicenter Case–Control Study

Background: We investigated associations between tobacco exposure, history of schistosomiasis, and bladder cancer risk in Egypt. Methods: We analyzed data from a case–control study (1,886 newly diagnosed and histologically confirmed cases and 2,716 age-, gender-, and residence-matched, population-based controls). Using logistic regression, we estimated the covariate-adjusted ORs and 95% confidence interval (CI) of the associations. Results: Among men, cigarette smoking was associated with an increased risk of urothelial carcinoma (OR = 1.8; 95% CI, 1.4–2.2) but not squamous cell carcinoma (SCC); smoking both water pipes and cigarettes was associated with an even greater risk for urothelial carcinoma (OR = 2.9; 95% CI, 2.1–3.9) and a statistically significant risk for SCC (OR = 1.8; 95% CI, 1.2–2.6). Among nonsmoking men and women, environmental tobacco smoke exposure was associated with an increased risk of urothelial carcinoma. History of schistosomiasis was associated with increased risk of both urothelial carcinoma (OR = 1.9; 95% CI, 1.2–2.9) and SCC (OR = 1.9; 95% CI, 1.2–3.0) in women and to a lesser extent (OR = 1.4; 95% CI, 1.2–1.7 and OR = 1.4; 95% CI, 1.1–1.7, for urothelial carcinoma and SCC, respectively) in men. Conclusions: The results suggest that schistosomiasis and tobacco smoking increase the risk of both SCC and urothelial carcinoma. Impact: This study provides new evidence for associations between bladder cancer subtypes and schistosomiasis and suggests that smoking both cigarettes and water pipes increases the risk for SCC and urothelial carcinoma in Egyptian men. Cancer Epidemiol Biomarkers Prev; 21(3); 537–46. ©2011 AACR.

Selective cyclooxygenase-2 (COX-2) inhibitors and breast cancer risk

BACKGROUNDnRecent epidemiologic and laboratory studies have suggested that non-steroidal anti-inflammatory drugs (NSAIDs) may reduce the risk of breast cancer through inhibition of cyclooxygenase-2 (COX-2).nnnMETHODSnWe conducted a case-control study to measure the association between selective cox-2 inhibitors, particularly celecoxib, rofecoxib, valdecoxib and non-specific NSAID subgroups, and breast cancer risk. Between 2003 and 2006, a total of 18,368 incident breast cancer cases were identified in the Ingenix/Lab Rx insurance database, which contains clinical encounter and drug prescription data. Four controls per case were randomly selected, matched on age and time in database. Odds ratios (OR) and 95% confidence intervals (CI) were estimated using conditional logistic regression.nnnRESULTSnBreast cancer risk was inversely associated with both non-specific NSAID and selective COX-2 inhibitor use. Greater than 12 months duration of use of Celecoxib at a standard dose (200mg/day) was associated with a 16% decrease in breast cancer risk (OR=0.84, 95% CI=0.73, 0.97). We observed the greatest risk reduction in association with >2 years of rofecoxib exposure (OR=0.54, 95% CI=0.37, 0.80). Acetaminophen, a compound with less biological plausibility for chemoprevention, showed no significant association with the risk of developing breast cancer.nnnCONCLUSIONnConsistent with animal models and laboratory investigations, higher doses of selective COX-2 inhibitors were more protective against breast cancer than non-specific NSAIDs. With exposure to rofecoxib, a selective COX-2 inhibitor, breast cancer risk reduction was appreciable (46%), suggesting a possible role for selective COX-2 inhibitors in breast cancer prophylaxis.

Prostate cancer screening 2010: updated recommendations from the American Cancer Society.

In 2009, the American Cancer Society (ACS) initiated a series of systematic evidence reviews to update recommendations for early prostate cancer detection. The evidence reviews focused on studies of screening, the performance of screening tests, harms associated with testing and therapy for localized prostate cancer, and shared and informed decision making in prostate cancer screening. Based on this evidence, the ACS recommends that asymptomatic men who have at least a 10-year life expectancy have an opportunity to make an informed decision with their health care provider about screening for prostate cancer after receiving information about the uncertainties, risks, and potential benefits associated with prostate cancer screening. Prostate cancer screening should not occur without an informed decision-making process. Men at average risk should receive this information beginning at age 50. Men in higher-risk groups should receive this information before age 50. Men should either receive this information directly from their health care providers or be referred to reliable and culturally appropriate sources. Patient decision aids are helpful in preparing men to make a decision whether to be tested, and the use of such aids is encouraged.

Using Pathway-Specific Comprehensive Exposure Scores in Epidemiology: Application to Oxidative Balance in a Pooled Case-Control Study of Incident, Sporadic Colorectal Adenomas

Identifying associations of risk factors sharing the same pathway with disease risk is complicated by small individual effects and intercorrelated components; this can be addressed by creating comprehensive exposure scores. We developed and validated 3 novel weighting methods (literature review-derived, study data-based, and a Bayesian method that combines prior knowledge with study data) to incorporate components into a pathway score for oxidative balance in addition to a commonly used method that assumes all components contribute equally to the score. We illustrate our method using pooled data from 3 US case-control studies of sporadic colorectal adenoma (1991-2002). We created 4 oxidative balance scores (OBS) to reflect combined summary measures of dietary and nondietary antioxidant and prooxidant exposures. A higher score represents a predominance of antioxidant exposures over prooxidant exposures. In the pooled data, the odds ratios comparing the highest tertile of OBS with the lowest for adenoma risk ranged from 0.38 to 0.54 for the 4 measures; all were statistically significant. These findings suggest that 1) OBS are indicators of oxidative balance and may be inversely associated with colorectal adenoma risk and 2) using comprehensive exposure scores may be preferable to investigating individual component-disease associations for complex exposures, such as oxidative balance.