Chinese Anti-Cancer Association as a non-governmental organization undertakes systematic cancer prevention work in China

Cancer has become the first leading cause of death in the world, particularly in low- and middle-income countries. Facing the increasing trend of cancer incidence and mortality, China issued and implemented ＂three-early（early prevention, early diagnosis and early treatment）＂ national cancer prevention plan. As the main body and dependence of social governance, non-governmental organizations（NGOs） take over the role of government in the field of cancer prevention and treatment. American Cancer Society（ACS） made a research on cancer NGOs and civil society in cancer control and found that cancer NGOs in developing countries mobilize civil society to work together and advocate governments in their countries to develop policies to address the growing cancer burden. Union for International Cancer Control（UICC）, Cancer Council Australia（CCA）, and Malaysian cancer NGOs are the representatives of cancer NGOs in promoting cancer control. Selecting Chinese Anti-Cancer Association（CACA） as an example in China, this article is to investigate how NGOs undertake systematic cancer prevention work in China. By conducting real case study, we found that, as a NGO, CACA plays a significant role in intensifying the leading role of government in cancer control, optimizing cancer outcomes, decreasing cancer incidence and mortality rates and improving public health.

Unlocking the potential-vitamin D in prostate cancer prevention

Prostate cancer poses a significant health challenge globally,demanding proactive prevention strategies.This editorial explores the emerging role of vitamin D in prostate cancer prevention.While traditionally associated with bone health,vitamin D is increasingly recognized for its broader impact on immune function,cellular signaling,and cancer prevention.Epidemiological studies suggest an intriguing link between vitamin D deficiency and elevated prostate cancer risk,particularly in regions with limited sunlight exposure.Mechanistically,vitamin D regulates cellular processes,inhibiting unchecked cancer cell growth and bols-tering immune surveillance.Personalized prevention strategies,considering individual factors,are deemed essential for harnessing the full potential of vitamin D.To unlock this potential,the future calls for robust research,public awareness campaigns,dietary improvements,and vigilant medical guidance.Collaborative efforts are poised to pave the way toward a future where vitamin D stands as a sentinel in prostate cancer prevention,ushering in hope and improved health for men worldwide.

Effectiveness of serological markers of gastric mucosal atrophy in the gastric precancer screening and in cancer prevention

BACKGROUND New markers are needed to improve the effectiveness of serological screening for atrophic gastritis.AIM To develop a cost-effective method for serological screening of atrophic gastritis with a high level of sensitivity.METHODS Of the 169 patients with atrophic gastritis,selected by the visual endoscopic Kimura-Takemoto method,165 showed histological mucosal atrophy using the updated Kimura-Takemoto method.All 169 patients were examined for postprandial levels of gastrin-17(G17)and pepsinogen-1(PG1)using Gastro-Panel®(Biohit Plc,Helsinki,Finland).RESULTS We used the histological standard of five biopsies of the gastric mucosa,in accordance with the Kimura-Takemoto classification system to assess the sensitivity of G17 in detecting gastric mucosal atrophy.We also compared the morphofunctional relationships between the detected histological degree of gastric mucosal atrophy and the serological levels of G17 and PG1,as the markers of atrophic gastritis.The sensitivity of postprandial G17 was 62.2%for serological levels of G17(range:0-4 pmol/L)and 100%for serological G17(range:0-10 pmol/L)for the detection of monofocal severe atrophic gastritis.No strong correlation was found between the levels of PG1 and degree of histological atrophy determined by the Kimura-Takemoto classification system to identify the severity of mucosal atrophy of the gastric corpus.In the presented clinical case of a 63-year-old man with multifocal atrophic gastritis,there is a pronounced positive long-term dynamics of the serological marker of atrophy-postprandial G17,after five months of rennet replacement therapy.CONCLUSION Serological screening of multifocal atrophic gastritis by assessment of postprandial G17 is a cost-effective method with high sensitivity.Postprandial G17 is an earlier marker of regression of atrophic gastritis than a morphological examination of a gastric biopsy in accordance with the Sydney system.Therefore,postprandial G17 is recommended for dynamic monitoring of atrophic gastritis after treatment.

Helicobacter pylori eradication for primary prevention of gastric cancer:progresses and challenges

Gastric cancer remains a significant global health challenge,causing a substantial number of cancer-related deaths,particularly in China.While the exact causes of gastric cancer are still being investigated,Helicobac-ter pylori(H.pylori)infection has been identified as the primary risk factor,which triggers chronic inflammation and a multistage progression of gastric lesions that may lead to carcinogenesis over a long latency time.Since the 1990s,numerous efforts have focused on assessing the effectiveness of H.pylori eradication in preventing new cases of gastric cancer among both the general population and patients who have undergone early-stage cancer treatment.This body of work,including several community-based interventions and meta-analyses,has shown a reduction in both the incidence of and mortality from gastric cancer following H.pylori treatment,alongside a decreased risk of metachronous gastric cancer.In this review,we seek to consolidate current knowledge on the effects of H.pylori treatment on gastric cancer prevention,its systemic consequences,cost-effectiveness,and the influence of antibiotic resistance and host characteristics on treatment outcomes.We further discuss the potential for precision primary prevention of H.pylori treatment and comment on the efficient implementation of test-and-treat policies and allocation of health resources towards minimizing the burden of gastric cancer globally.

Unraveling colorectal cancer prevention:The vitamin D-gut flora-immune system nexus

Colorectal cancer(CRC)is one of the most common cancers diagnosed in the world.Although environmental and genetic factors play a major role in the pathogenesis of CRC,extensive research has suggested that vitamin D may play a pivotal role in the development of CRC.Vitamin D,primarily obtained through sunlight exposure,dietary sources,and supplements,has long been recognized for its essential functions in maintaining health,including immune regulation.This article delves into the intricate relationship between vitamin D,the immune system,gut flora,and the prevention of CRC.It presents a synthesis of epidemiological data,experimental studies,and clinical trials,highlighting the mechanisms by which vitamin D influences immune cell function,cytokine production,and inflammation.By enhancing the immune system’s surveillance and antitumor activity,vitamin D may offer a promising avenue for CRC prevention.Furthermore,this comprehensive review delves into the prospective clinical applications of vitamin D supplementation and delineates the forthcoming avenues of research in this dynamic domain.Additionally,the paper tentatively outlines a spectrum of prophylactic impacts of vitamin D on CRC,emphasizing its significant potential in reducing CRC risk through shedding light on its mechanisms,encompassing antineoplastic mechanisms,influences on the immune system,and modulation of the gut microbiome.

Assessment of Breast Cancer Prevention Practices among Women Attending Primary Health Care in Abha City, Aseer Region, Saudi Arabia

Cancer is a leading cause of death worldwide, with breast cancer being the most common (2.26 million new cases and 685,000 deaths). In Saudi Arabia, breast cancer ranked the first among females in 2014, accounting for 15.9% of all cancers reported among Saudi nationals and 28.7% of all cancers reported among females of all ages. Early detection of breast cancer could decrease the risks, have a better prognosis, and have better outcomes/more successful treatments. Prevalence of breast cancer reached more than 25% of all diagnosed cancer in the kingdom among women. Aim: This study aims to assess the knowledge and performance of women attending primary care centers about breast self-examination and mammogram screening for prevention and early detection of breast cancer in Abha city primary healthcare centers, Kingdom of Saudi Arabia. Research Method: cross sectional design was conducted by using questionnaire, which was distributed to primary care center nurses. The collected data was statistically analyzed using the Statistical Package for Social Sciences, version 25. Results: The study found that participants had poor awareness and knowledge about breast self-examination, risk factors for breast cancer, and trends and practices in early diagnosis of breast cancer. Conclusion and Recommendations: It recommends increasing awareness campaigns and providing educational programs to improve knowledge and practices.

Global strategy for prevention of gastric cancer

Global prevention of gastric cancer needs to increase its level of effectiveness.The prevention strategy should include all stages of primary and secondary prevention.The necessary steps to prevent gastric cancer are the following:Maintaining a healthy lifestyle and diet,avoiding smoking and alcohol;serological screening of Helicobacter pylori infections and eradication;serological screening of atrophic gastritis in the population over 45 years of age and identification of severe atrophic gastritis with a high risk of developing gastric cancer;verification of atrophic gastritis and precancerous changes in the gastric mucosa using modern endoscopic(confocal laser endomicroscopy,narrow-spectrum imaging,and magnifying endoscopy)and morphological methods among patients with severe atrophic gastritis who were identified using serological screening;treatment of patients with atrophic gastritis during diagnosis verification;annual endoscopic and morphological monitoring of patients with atrophic gastritis during permanent treatment;annual serological monitoring of patients with atrophic gastritis who refused endoscopic and morphological monitoring;and radical treatment of patients with verified early gastric cancer.Ways to implement the algorithm for the global strategy for the prevention of gastric cancer(protocol of practical recommendations)are:State,government,and municipal programs;departmental programs of health departments;family doctors for patients who have a contract at the initiative of the doctor;family doctors for patients with a contract at the patient’s initiative;and within private healthcare system where both doctors and patients can initiate the implementation of algorithm.

Vitamin D and prostate cancer prevention

Vitamin D is a hot topic nowadays,especially its relationship with cancer pre-vention.Normally,vitamin D is associated with bone health principally,but the new research has discovered an impact on immune function and cellular sig-naling,even in same studies talk about a hormone,however,the most important relationship is its implication in cellular processes,inhibiting cancer growth.For now,the recent studies are oriented about a benefit and a cause-effect relationship between prostate cancer and normal levels of vitamin D.This premise opens a lot of questions in this scenario.This editorial highlighted the most important studies in this area.

Anti-Cancer Agents Associated Diarrhea:Current Status and Prospects

Cancer stands as one of the major threats to human life.Ensuring the safety of drugs is paramount,and the impact of adverse reactions on patients’quality of life and prognosis should not be underestimated.Diarrhea is a common clinical adverse event,and despite the absence of specific anti-diarrhea drugs,there is a pressing need for improvement.This article aims to provide a valuable reference for researchers in clinical drug use and scientific tumor treatment.It summarizes recent advancements in drug mechanisms and adverse reactions,whether in preclinical research or clinical diagnosis and therapy.

Colorectal cancer: From prevention to personalized medicine

Colorectal cancer(CRC)is a very heterogeneous disease that is caused by the interaction of genetic and environmental factors.CRC develops through a gradual accumulation of genetic and epigenetic changes,leading to the transformation of normal colonic mucosa into invasive cancer.CRC is one of the most prevalent and incident cancers worldwide,as well as one of the most deadly.Approximately 1235108 people are diagnosed annually with CRC,and 609051 die from CRC annually.The World Health Organization estimates an increase of77%in the number of newly diagnosed cases of CRCand an increase of 80%in deaths from CRC by 2030.The incidence of CRC can benefit from different strategies depending on its stage:health promotion through health education campaigns(when the disease is not yet present),the implementation of screening programs(for detection of the disease in its early stages),and the development of nearly personalized treatments according to both patient characteristics(age,sex)and the cancer itself(gene expression).Although there are different strategies for screening and although the number of such strategies is increasing due to the potential of emerging technologies in molecular marker application,not all strategies meet the criteria required for screening tests in population programs;the three most accepted tests are the fecal occult blood test(FOBT),colonoscopy and sigmoidoscopy.FOBT is the most used method for CRC screening worldwide and is also the primary choice in most population-based screening programs in Europe.Due to its non-invasive nature and low cost,it is one of the most accepted techniques by population.CRC is a very heterogeneous disease,and with a few exceptions(APC,p53,KRAS),most of the genes involved in CRC are observed in a small percentage of cases.The design of genetic and epigenetic marker panels that are able to provide maximum coverage in the diagnosis of colorectal neoplasia seems a reasonable strategy.In recent years,the use of DNA,RNA and protein markers in different biological samples has been explored as strategies for CRC diagnosis.Although there is not yet sufficient evidence to recommend the analysis of biomarkers such as DNA,RNA or proteins in the blood or stool,it is likely that given the quick progression of technology tools in molecular biology,increasingly sensitive and less expensive,these tools will gradually be employed in clinical practice and will likely be developed in mass.

Association of cancer prevention awareness with esophageal cancer screening participation rates: Results from a population-based cancer screening program in rural China

Objective: : China have implemented population-based esophageal cancer(EC) screening programs, however,the participant rates were relatively low. This study was conducted to examine the association between cancer prevention knowledge and EC screening participation rates(PRs).Methods: : Data in the analyses were obtained from a population-based cancer screening program in four provinces in China since 2007. In the course of 2007-2016, participants who were evaluated as high risk for EC and subsequently recommended for endoscopy examination were included in the final analysis. One-way analysis of variance test, Chi-square test and logistic regression analysis were applied.Results: : A total of 28,543 individuals assessed as high-risk population for EC were included in this study, with13,036 males(45.67%) and 15,507 females(54.33%). The prevalence rates of current smoking and alcohol drinking were higher in males(58.25% and 44.22%, respectively) than in females(5.35% and 4.05%, respectively).Participants of females, and those who had older age, lower income, as well as higher education level and cancer prevention knowledge level were more likely to undergo endoscopy. Multivariable analysis showed that higher cancer prevention knowledge was associated with higher PR for endoscopic screening [adjusted odd ratio(aORQ4/Q1) =1.511, 95% confidence interval(95% CI): 1.398-1.632] among our study subjects. This association between cancer prevention knowledge and compliance with endoscopic screening also tends to be strong within subgroups of males, females, aged below 60 years, aged 60 years and above, and lower level of education(illiterate individuals and those with junior high education or less).Conclusions: : Our results displayed a positive relationship between cancer prevention knowledge and PRs for endoscopic screening, implying cancer prevention awareness being an independent influence factor for compliance with EC screening. Promoting public campaigns about comprehensive knowledge of cancer prevention seemed to be a reasonable and effective strategy to improve population PRs for EC screening.

Cancer burden in China:trends,risk factors and prevention

As the most populous country in the world,China has made strides in health promotion in the past few decades.With the aging population,the burden of cancer in China continues to grow.Changes in risk factors for cancer,especially diet,obesity,diabetes,and air pollution,continue to fuel the shift of cancer transition in China.The burden of upper gastrointestinal cancer in China is decreasing,but still heavy.The rising burden of colorectal,prostate,and breast cancers is also significant.Lung cancer became the top cause of cancer-related deaths,together with smoking as the most important contributor to cancer deaths.The Chinese government has taken several approaches to control cancer and cancer-related risk factors.Many achievements have been made,but some challenges remain.Health China 2030 is ambitious and depicts a bright vision of the future for cancer control in China.The decrease in the cancer burden in China will require cross-sector collaboration and coordinated efforts on primary and secondary preventions by governments,public health organizations,and individuals.In this review,we describe the trends of cancer burden and discuss cancer-related risk factors in China,identifying strategies to reduce the burden of cancer in China.

Current cancer burden in China: epidemiology, etiology, and prevention

Cancer has become the most common cause of death in China.Owing to rapid economic development,improved livelihood,and shifts in risk factors,cancer epidemiology has experienced substantial changes during the past several decades.In this review,we aim to describe the current cancer epidemiology of the main types of cancer in China,report major risk factors associated with cancer development,and summarize the contributions of the Chinese government to controlling the cancer burden.A total of 4,064,000 new cases were diagnosed in China in 2016.The most frequent types are lung cancer(828,100;20.4%),colorectal cancer(408,000;10.0%),and gastric cancer(396,500;9.8%).Lung(657,000;27.2%),liver(336,400,13.9%),and stomach(288,500;12.0%)cancers are the 3 most deadly cancers in the general population.The 5-year survival rate for cancer has dramatically increased in recent decades.However,liver and particularly pancreatic cancers still have the poorest prognosis.The main modifiable risk factors associated with cancer development include infectious agents,smoking,alcohol consumption,obesity,unhealthful dietary habits,and inadequate physical activity.The Chinese government has made unremitting efforts to decrease the cancer burden,including cancer education and investment in cancer screening programs.

Gastric cancer: Epidemiology, risk factors and prevention strategies

Gastric cancer(GC) is a global health problem, with more than 1 million people newly diagnosed with GC worldwide each year. GC is more prevalent in less developed countries than in more developed countries. About half of all GC cases worldwide occur in East Asia, notably China. Globally, overall incidence rates of GC are declining, which is potentially attributed to a decrease in Helicobacter pylori(H. pylori) infection and the use of refrigeration to preserve foods rather than salt. GC is a multifactorial disease, and its occurrence and development were impacted by environmental and genetic factors. H. pylori infection is the primary risk factor for GC, especially for non-cardia. The prognosis of GC is poor due to stages at the first diagnosis. The 5-year survival rate is less than 10% when patients are diagnosed at an advanced stage, but the rate is as high as 85% if patients are detected at an earlier stage. Endoscopic screening can potentially prevent GC by early diagnosis and early treatment and has been widely adopted in screening programs in East Asian countries, such as Japan and Korea. This review summarizes updated epidemiological aspects, risk factors, and prevention strategies of GC in recent years to help researchers determine the most effective intervention strategies for reducing risk of GC.

External validation of the Prostate Cancer Prevention Trial and the European Randomized Study of Screening for Prostate Cancer risk calculators in a Chinese cohort

Several prediction models have been developed to estimate the outcomes of prostate biopsies. Most of these tools were designed for use with Western populations and have not been validated across different ethnic groups. Therefore, we evaluated the predictive value of the Prostate Cancer Prevention Trial （PCPT） and the European Randomized Study of Screening for Prostate Cancer （ERSPC） risk calculators in a Chinese cohort. Clinicopathological information was obtained from 495 Chinese men who had undergone extended prostate biopsies between January 2009 and March 2011. The estimated probabilities of prostate cancer and high-grade disease （Gleason 〉6） were calculated using the PCPT and ERSPC risk calculators. Overall measures, discrimination, calibration and clinical usefulness were assessed for the model evaluation. Of these patients, 28.7% were diagnosed with prostate cancer and 19.4% had high-grade disease. Compared to the PCPT model and the prostate-specific antigen （PSA） threshold of 4 ng m1-1, the ERSPC risk calculator exhibited better discriminative ability for predicting positive biopsies and high-grade disease （the area under the curve was 0.831 and 0.852, respectively, P〈O.01 for both）. Decision curve analysis also suggested the favourable clinical utility of the ERSPC calculator in the validation dataset. Both prediction models demonstrated miscalibration： the risk of prostate cancer and high-grade disease was overestimated by approximately 20% for a wide range of predicted probabilities. In conclusion, the ERSPC risk calculator outperformed both the PCPT model and the PSA threshold of 4 ng ml- z in predicting prostate cancer and high-grade disease in Chinese patients. However, the prediction tools derived from Western men significantly overestimated the probability of prostate cancer and high-grade disease compared to the outcomes of biopsies in a Chinese cohort.

Advances in gastric cancer prevention

Gastric cancer is a multifactorial neoplastic pathology numbering among its causes both environmental and genetic predisposing factors. It is mainly diffused in South America and South-East Asia, where it shows the highest morbility percentages and it is relatively scarcely diffused in Western countries and North America. Although molecular mechanisms leading to gastric cancer development are only partially known, three main causes are well characterized: Helicobacter pylori(H. pylori) infection, diet rich in salted and/or smoked food and red meat, and epithelial cadherin(E-cadherin) mutations. Unhealthy diet and H. pylori infection are able to induce in stomach cancer cells genotypic and phenotypic transformation, but their effects may be crossed by a diet rich in vegetables and fresh fruits. Various authors have recently focused their attention on the importance of a well balanced diet, suggesting a necessary dietary education starting from childhood. A constant surveillance will be necessary in people carrying E-cadherin mutations, since they are highly prone in developing gastric cancer, also within the inner stomach layers. Above all in the United States, several carriers decided to undergo a gastrectomy, preferring changing their lifestyle than living with the awareness of the development of a possible gastric cancer. This kind of choice is strictly personal, hence a decisioncannot be suggested within the clinical management. Here we summarize the key points of gastric cancer prevention analyzing possible strategies referred to the different predisposing factors. We will discuss about the effects of diet, H. pylori infection and E-cadherin mutations and how each of them can be handled.

Burden of liver cancer:From epidemiology to prevention

In this review,we offer a concise overview of liver cancer epidemiology in China and worldwide from the official databases of GLOBOCAN 2020 and the National Cancer Registry in China.We also summarized the evidence for the main risk factors associated with liver cancer risk and discuss strategies implemented in China to control the liver cancer burden.Overall,liver cancer was the sixth most commonly diagnosed cancer and the third leading cause of cancer-related death worldwide in 2020.Although China contributed to nearly half of cases across the world alone,the incidence and mortality rates of liver cancer presented a declining trend owing to the persistent efforts from the governments at all levels.The current liver cancer burden in China still faces an arduous challenge due to the relatively large population base as well as the substantially low survival rate(12.1%).To better control the liver cancer burden with the lowest cost,specific measures should be conducted by reducing exposure to established risk factors such as hepatitis B infection and aflatoxin.The promotion of surveillance is also an important method to prolong the survival of liver cancer.This review will provide basic information for future direction on the control of liver cancer burden.

Stomach cancer burden in China: Epidemiology and prevention

In 2020, stomach cancer was the fifth most commonly diagnosed cancer and the fourth leading cause of cancer-related death worldwide. Due to the relatively huge population base and the poor survival rate, stomach cancer is still a threat in China, and accounts for nearly half of the cases worldwide. Fortunately, in China, the incidence and mortality rates of stomach cancer presented a declining trend owing to the change of individual life styles and the persistent efforts to prevent stomach cancer from the governments at all levels. Helicobacter pylori(H. pylori)infection, poor eating habits, smoking, history of gastrointestinal disorders, and family history of stomach cancer are the main risk factors for stomach cancer in China. As a result, by taking risk factors for stomach cancer into account, specific preventive measures, such as eradicating H. pylori and implementing stomach cancer screening projects, should be taken to better prevent and decrease the burden of stomach cancer.

Chemoprevention of gastric cancer development after Helicobacter pylori eradication therapy in an East Asian population:Meta-analysis

BACKGROUND Helicobacter pylori(H.pylori)infection is a risk factor for gastric cancer(GC),especially in East Asian populations.Most East Asian populations infected with H.pylori are at higher risk for GC than H.pylori-positive European and United States populations.H.pylori eradication therapy reduces gastric cancer risk in patients after endoscopic and operative resection for GC,as well as in non-GC patients with atrophic gastritis.AIM To clarify the chemopreventive effects of H.pylori eradication therapy in an East Asian population with a high incidence of GC.METHODS PubMed and the Cochrane library were searched for randomized control trials(RCTs)and cohort studies published in English up to March 2019.Subgroup analyses were conducted with regard to study designs(i.e.,RCTs or cohort studies),country where the study was conducted(i.e.,Japan,China,and South Korea),and observation periods(i.e.,≤5 years and>5 years).The heterogeneity and publication bias were also measured.RESULTS For non-GC patients with atrophic gastritis and patients after resection for GC,4 and 4 RCTs and 12 and 18 cohort studies were included,respectively.In RCTs,the median incidence of GC for the untreated control groups and the treatment groups was 272.7(180.4–322.4)and 162.3(72.5–588.2)per 100000 person-years in non-GC cases with atrophic gastritis and 1790.7(406.5–2941.2)and 1126.2(678.7–1223.1)per 100000 person-years in cases of after resection for GC.Compared with non-treated H.pylori-positive controls,the eradication groups had a significantly reduced risk of GC,with a relative risk of 0.67[95%confidence interval(CI):0.47–0.96]for non-GC patients with atrophic gastritis and 0.51(0.36–0.73)for patients after resection for GC in the RCTs,and 0.39(0.30–0.51)for patients with gastritis and 0.54(0.44–0.67)for patients after resection in cohort studies.CONCLUSION In the East Asian population with a high risk of GC,H.pylori eradication effectively reduced the risk of GC,irrespective of past history of previous cancer.

Primary prevention of colorectal cancer:Myth or reality?

Colorectal cancer incidence has been rising strongly in parallel with economic development.In the past few decades,much has been learned about the lifestyle,dietary and medication risk factors for this malignancy.With respect to lifestyle,compelling evidence indicates that prevention of weight gain and maintenance of a reasonable level of physical activity can positively influence in lowering the risk.Although there is controversy about the role of specific nutritional factors,consideration of dietary pattern as a whole appears useful for formulating recommendations.Though quite often recommended,the role for many supplements,including omega-3,vitamin D,folate,and vitamin B6,remains unsettled.Only calcium and vitamin D supplementation appear to add a modest benefit,particularly in those with a low daily intake.With regard to chemoprevention,medications such as aspirin and nonsteroidal antiinflammatory drugs,and postmenopausal hormonal replacement for women might be associated with substantial reductions in colorectal cancer risk,though their utility is affected by their side effect profile.However,the role of agents such as statins,bisphosphonates and antioxidants have yet to be determined.Ultimately,primary prevention strategies focusing on modifying environmental,lifestyle risk factors,and chemopreventive drugs are options that have already been tested,and may impact on colon cancer incidence.