Epidemiology and risk factors for pancreatic cancer

Pancreas cancer is considered an 'orphan' cancer because of its relative low incidence. Unfortunately even with early diagnosis, mortality rates are high, explaining why, despite the low incidence, it ranks eighth in a world listing of cancer mortality. International incidence rates vary in different countries, implying that environmental factors are important. Of these factors, smoking is the most well documented etiologic agent, explaining about 25% of all cases. Dietary factors may be important, but it has been difficult to define specific items which either increase or decrease the risk of pancreatic cancer. Since the incidence of pancreas cancer is so strongly age-dependent, we can anticipate an increasing number of patients as the population of most Western countries ages.     

Epidemiology of pancreatic cancer: an update

Pancreatic cancer, although infrequent, has a very poor prognosis, making it one of the 4 or 5 most common causes of cancer mortality in developed countries. Its incidence varies greatly across regions, which suggests that lifestyle factors such as diet, and environmental factors, such as vitamin D exposure, play a role. Because pancreatic cancer is strongly age-dependent, increasing population longevity and ageing will lead to an increase of the global burden of pancreatic cancer in the coming decades. Smoking is the most common known risk factor, causing 20-25% of all pancreatic tumors. Although a common cause of pancreatitis, heavy alcohol intake is associated only with a modest increased risk of pancreatic cancer. While viruses do not represent a major risk factor, people infected with Helicobacter pylori appeared to be at high risk of pancreatic cancer. Many factors associated with the metabolic syndrome, including overweight and obesity, impaired glucose tolerance, and long-standing diabetes also increase the risk disease, while atopic allergy and use of metformin as a treatment for diabetes have been associated with a reduced risk of pancreatic cancer. A family history of pancreatic cancer is associated with an increased risk of pancreatic cancer and it is estimated that 5-10% of patients with pancreatic cancer have an underlying germline disorder. Having a non-O blood group, another inherited characteristic, has also been steadily associated with an increased risk of pancreatic cancer. While many risk factors for pancreatic cancer are not modifiable, adopting a healthy lifestyle could substantially reduce pancreatic cancer risk.     

Molecular epidemiology of pancreatic cancer

Pancreatic cancer is the fourth leading cause of cancer-related death in the United States. Currently there is no early diagnostic test and no effective treatment options for this deadly disease. Prevention of pancreatic cancer is difficult because little is known about its etiology. The main modifiable risk factors for pancreatic cancer include cigarette smoking and dietary factors. Information from molecular epidemiological study of pancreatic cancer is very limited. DNA adducts derived from exposure to polycyclic aromatic hydrocarbon, aromatic amines, and heterocyclic amines have been detected in human pancreatic tissues. DNA damages derived from oxidative stress and lipid peroxidation are also present in pancreas. No study has demonstrated a main effect of carcinogen-metabolizing genes and DNA repair genes on the risk of pancreatic cancer thus far. However, significant effects of these genes have been observed among individuals with known carcinogen exposure, such as smoking. A number of environmental and lifestyle factors, such as smoking, alcohol, coffee consumption, and exposure to organochlorine or hydrocarbon solvent, have been associated with the frequency and spectrum of K-ras mutation in pancreatic tumors. Dietary folate intake and serum levels of folate have been associated with the risk of pancreatic cancer among male smokers. These findings demonstrate the potential of the molecular epidemiology approach in understanding the etiology of pancreatic cancer. Further efforts should be made to understand the interactive relationship between genetic and environmental factors in the etiology of pancreatic cancer, which will in turn be important in identifying the high-risk population for the primary prevention of this deadly disease.     

Prevention of cardiovascular diseases: should the same criteria be applied in Latin America and Europe and North America?

The prevention of cardiovascular diseases is based on the management of known cardiovascular risk factors by pharmacological means or by modifying lifestyles. A reduction in cholesterol levels is associated with a lower incidence of cardiovascular events and mortality, in both primary or secondary prevention trials. A reduction in blood pressure also leads to a decrease in acute myocardial infarction and the incidence of stroke. Regular exercise is associated with better disease free survival and the effects of smoking cessation are well known. High homocysteine levels are also associated with cardiovascular disease. However, there are no prospective clinical trials showing a beneficial effect of homocysteine reduction on cardiovascular mortality. A change in the type of dietary fat should also be beneficial, but this has not been proven in prospective clinical trials. In Chile, cardiovascular diseases are the leading cause of death among adults and the prevalence of cardiovascular risk factors, including hyperhomocysteinemia is similar to that of European or North American populations. Successful primary and secondary prevention programs to manage these risk factors have been developed in Chile. Therefore, the criteria applied in North America and Europe for the prevention of cardiovascular diseases, should be applied with slight modifications, in Latin American Countries.     

Epidemiology, etiology, and prevention of lung cancer

Over the past century, lung cancer has gone from an obscure disease to the leading cause of cancer death worldwide. Initially an epidemic disease among men in industrialized nations, lung cancer now has become the leading cancer killer in both sexes in the United States and an increasingly common disease of both sexes in developing countries. Lung cancer incidence largely mirrors smoking prevalence, with a latency period of several decades. Other important risk factors for the development of lung cancer include environmental exposure to tobacco smoke, radon, occupational carcinogens, and pre-existing nonmalignant lung disease. Studies in molecular biology have elucidated the role that genetic factors play in modifying an individual's risk for lung cancer. Although chemopreventive agents may be developed to prevent lung cancer, prevention of smoking initiation and promotion of smoking cessation are currently the best weapons to fight lung cancer. No other malignancy has been shown to have such a strong epidemiologic relation between a preventable behavior and incidence of disease. Despite this knowledge, more than 20% of all Americans smoke, and tobacco use is exploding in developing countries. Based on current and projected smoking patterns, it is anticipated that lung cancer will remain the leading cause of cancer death in the world for decades to come.     

Primary prevention of cancer: priorities for practical implementation and research

In CMEA countries among all malignant neoplasms lung cancer ranks as a first both in incidence and mortality followed by stomach, breast and cervical cancer, lung and breast cancer being on increase, while stomach and cervical cancer have been decreasing. To the most important causes of cancer belong smoking, excessive alcohol consumption, certain occupational exposures, ambient-air pollution. Therefore, the priorities in cancer prevention and control in the CMEA countries should be directed towards complete removal or reduction in the exposure to these risk factors. Modification of diet, most probably, would reduce the frequency of some of the aforgoing cancers and first of all cancer of the stomach.     

Cancer in the elderly: is it preventable?

It is the goal of the American Cancer Society to decrease the mortality from cancer by 50% and the incidence of cancer by 25% by the year 2015 in the United States. Achieving this goal requires intervention at the primary (incidence) and secondary (mortality) prevention stages, and will involve a concerted effort of the individual practitioner, governmental agencies, local, state, and national interest groups, and the population at large. Primary care practitioners must increase their level of enthusiasm for cancer prevention, and actively counsel patients about cancer risks and preventive measures. Practitioners should encourage inclined patients by providing support and specialty resources, such as dieticians, exercise therapists, and smoking and alcohol cessation programs. The greatest effort lies in the general population, who must adopt a healthier lifestyle, including appropriate diet, smoking cessation, control of obesity, and daily exercise. None of these lifestyle changes are easy to embrace, but once educated about lifestyle and risk of cancer, people have a powerful incentive to change. Continued public awareness campaigns and encouragement from health care providers are essential for the success of such programs. The success in smoking cessation shows that achieving societal lifestyle changes on a large scale is possible. The elderly are especially prone to benefit from primary and secondary prevention techniques, and it must not be assumed that only the young will realize the benefits of prevention and screening. The association of age and cancer risk will always be present, but need not be as consequential as it is now. Although cancer prevention may have a limited role in antiaging per se, the feasibility of cancer risk reduction has a definite role in aging successfully.     

Epidemiology of gastric cancer

The incidence and mortality of gastric cancer havefallen dramatically in US and elsewhere over the pastseveral decades.Nonetheless,gastric cancer remains amajor public health issue as the fourth most commoncancer and the second leading cause of cancer deathworldwide.Demographic trends differ by tumor locationand histology.While there has been a marked declinein distal,intestinal type gastric cancers,the incidence ofproximal,diffuse type adenocarcinomas of the gastriccardia has been increasing,particularly in the Westerncountries.Incidence by tumor sub-site also varieswidely based on geographic location,race,and socio-economic status.Distal gastric cancer predominates indeveloping countries,among blacks,and in lower socio-economic groups,whereas proximal tumors are morecommon in developed countries,among whites,and inhigher socio-economic classes.Diverging trends in theincidence of gastric cancer by tumor location suggestthat they may represent two diseases with differentetiologies.The main risk factors for distal gastric cancerinclude Helicobacter pylori(H pylori)infection anddietary factors,whereas gastroesophageal reflux diseaseand obesity play important roles in the development ofproximal stomach cancer.The purpose of this review isto examine the epidemiology and risk factors of gastriccancer,and to discuss strategies for primary prevention.     

Current status and progress of pancreatic cancer in China

Cancer is currently one of the most important public health problems in the world. Pancreatic cancer is a fatal disease with poor prognosis. As in most other countries, the health burden of pancreatic cancer in China is increasing, with annual mortality rates almost equal to incidence rates. The increasing trend of pancreatic cancer incidence is more significant in the rural areas than in the urban areas. Annual diagnoses and deaths of pancreatic cancer in China are now beyond the number of cases in the United States. GLOBOCAN 2012 estimates that cases in China account for 19.45% (65727/337872) of all newly diagnosed pancreatic cancer and 19.27% (63662/330391) of all deaths from pancreatic cancer worldwide. The population’s growing socioeconomic status contributes to the rapid increase of China’s proportional contribution to global rates. Here, we present an overview of control programs for pancreatic cancer in China focusing on prevention, early diagnosis and treatment. In addition, we describe key epidemiological, demographic, and socioeconomic differences between China and developed countries. Facts including no nationwide screening program for pancreatic cancer, delay in early detection resulting in a late stage at presentation, lack of awareness of pancreatic cancer in the Chinese population, and low investment compared with other cancer types by government have led to backwardness in China’s pancreatic cancer diagnosis and treatment. Finally, we suggest measures to improve health outcomes of pancreatic cancer patients in China.     

Epidemiological trends in pancreatic neoplasias

Primary prevention is the most effective approach to reduce the incidence of pancreatic cancer. Epidemiological studies have contributed to the identification of risk factors for pancreatic cancer, suggesting an association with age, various medical conditions, environmental and lifestyle risk factors, and occupational and genetic conditions. Age is the strongest risk factor. The most consistently identified environmental risk factor is smoking, but there is less certainty concerning dietary factors. Studies have suggested a positive association with high energy intake, cholesterol and meat, while vegetable and fruit intakes are probably protective. Patients with chronic pancreatitis and new onset of diabetes mellitus have a low but increasing risk of having or developing pancreatic cancer. There is strong evidence for the association of hereditary pancreatitis or cystic diseases of the pancreas and pancreatic cancer. A family history of pancreatic cancer is an important risk factor, but only a small proportion can be linked with known familial cancer syndromes. Thus, additional yet unidentified predisposing risk factors have to be assumed.     

Smoking cessation would substantially reduce the future incidence of pancreatic cancer in the European Union

OBJECTIVE: Since pancreatic cancer is one of the most rapidly fatal cancers, prevention is of paramount importance to reduce the future burden of this disease. We studied the impact of ceasing smoking on the future incidence of pancreatic cancer in the European Union (EU). METHODS: We developed a computer simulation model, Markov multi-state type, using country-specific published data on population sizes, smoking behaviour, pancreatic cancer incidence and total mortality rates, corresponding relative risks for ex- and current smokers, and estimated probabilities of starting and ceasing smoking (transition rates), with which we refined previously reported preliminary results. We simulated a scenario based on theoretically maximal smoking reduction, a more feasible scenario based on the World Health Organization's 'Health for All' target in which smoking prevalence is reduced to 20% in 2015, and scenarios based on reductions in smoking prevalence in 20 steps of 5% (from 0% to 100% reduction) in 2015. Simulations were based on changes in transition rates for smoking behaviour. We estimated the absolute and relative reduction of pancreatic cancer patients in the EU, for each scenario compared to a reference scenario in which the current transition rates remained unchanged, for the period 1994-2015. RESULTS: Theoretically, if all smokers would quit instantly, the estimated number of new pancreatic cancer patients up to 2015 in the EU could be reduced by 15% (around 150 000 patients). The more feasible scenario would lead to a reduction of almost 29 500 male and 9500 female patients. These results corresponded to a reduction in smoking prevalence with around 45% and 30% among men and women, respectively, in each EU country. CONCLUSION: Giving up smoking would substantially reduce the future incidence of pancreatic cancer. This emphasizes the importance of prevention in the reduction of the future pancreatic cancer burden.     

The epidemiology and impact of pancreatic diseases in the United States

In the United States, acute pancreatitis, chronic pancreatitis, and pancreatic cancer are the most common pancreatic disorders requiring diagnosis and treatment. Pancreatic cancer is responsible for nearly 30,000 annual deaths and is the second most common cause of death from any type of gastrointestinal disease. Gallstone disease, which is strongly associated with obesity, and excessive consumption of alcohol are the major risk factors for benign pancreatic disease, whereas smoking is the most important factor known to cause pancreatic cancer. Therefore, to reduce the overall burden of pancreatic disease, we should focus on the control of three lifestyle factors: smoking, drinking, and obesity.     

Epidemiology of cervical cancer (author's transl)]

There are remarkable differences of incidence and mortality from cervical cancer between countries and even within small countries. In developed industrial countries, incidence is slowly declining. Age distribution (middle--aged women are mostly afflicted) distinguishes cervical cancer from all other common malignant neoplasms. Known risk factors are: low social class, sexual activity early in youth, instable sexual relationships. Cervical cancer behaves like a veneral disease of low infectious power. Cervical cancer develops stepwise out of epithelial dysplasia and carcinoma in situ. The foundations of a cervical cancer control programme are laid: cytodiagnosis as screening method; well defined high risk groups; effective and not dangerous treatment of prephases and early stages of cancer. In the G.D.R. conditions for effective cancer control are good: cancer registration works stable for more than 20 years; it enables evaluation of effectivity. Cytologic screening can be fully integrated into basic gynecologic care. Medical care including prevention is free of fees and available for all women. The ultimate of goal of a cervical cancer control programme is primary prevention by detection and treatment of preneoplastic lesions (dysplasia and carcinoma in situ).     

Cardiovascular Risk Factors and Prevention: A Perspective From Developing Countries

By the beginning of the 21st century, cardiovascular disease (CVD) had become the leading cause of premature mortality and morbidity worldwide, with 80% originating from less developed lower-income countries in line with societal and economic developments. Extensive research on causes and risk factors have been carried out since the mid-20th century and have established individual factors such as smoking, hypertension, diabetes, and dyslipidemia as CVD risk factors, followed by others. Two recent major case-control studies have summarized the role of common major CVD risk factors in determining the risk of myocardial infarction (INTERHEART study) and stroke (INTERSTROKE study). They showed that 9 and 10 common risk factors accounted for > 90% of the risk of myocardial infarction and stroke, respectively, and established the focus in prevention of these common CVDs. The efficacy of lowering blood pressure, blood glucose, and lipid-lowering therapies has been shown to reduce subsequent morbidity and mortality. Leading international health organizations have published guidelines that are updated regularly to set the standards for providing guidance for implementation and management of risk factors. Interventions can also be costly and long-term adherence, essential to be effective in reducing risks, tends to decrease drastically with time. Dietary recommendations have been incorporated into national and professional guidelines for CVD prevention since the 1960s. On the basis of new research, some existing dietary recommendation might be outdated and should be reviewed, and revised, if necessary. A perspective of CVD prevention and treatment in developing countries is highlighted.     

Pancreatic cancer: A review of epidemiology,trend, and risk factors

Despite rapid advances in modern medical technology and significant improvements in survival rates of many cancers, pancreatic cancer is still a highly lethal gastrointestinal cancer with a low 5-year survival rate and difficulty in early detection. At present, the incidence and mortality of pancreatic cancer are increasing year by year worldwide, no matter in the United States, Europe, Japan, or China. Globally, the incidence of pancreatic cancer is projected to increase to 18.6 per 100000 in 2050, with the average annual growth of 1.1%, meaning that pancreatic cancer will pose a significant public health burden. Due to the special anatomical location of the pancreas, the development of pancreatic cancer is usually diagnosed at a late stage with obvious clinical symptoms. Therefore, a comprehensive understanding of the risk factors for pancreatic cancer is of great clinical significance for effective prevention of pancreatic cancer. In this paper, the epidemiological characteristics, developmental trends, and risk factors of pancreatic cancer are reviewed and analyzed in detail.     

Risk factors for pancreatic cancer: case-control study

OBJECTIVES: Although cigarette smoking is the most well-established environmental risk factor for pancreatic cancer, the interaction between smoking and other risk factors has not been assessed. We evaluated the independent effects of multiple risk factors for pancreatic cancer and determined whether the magnitude of cigarette smoking was modified by other risk factors in men and women. METHODS: We conducted a hospital-based case-control study involving 808 patients with pathologically diagnosed pancreatic cancer and 808 healthy frequency-matched controls. Information on risk factors was collected by personal interview, and unconditional logistic regression was used to determine adjusted odds ratios (AORs) by the maximum-likelihood method. RESULTS: Cigarette smoking, family history of pancreatic cancer, heavy alcohol consumption (>60 mL ethanol/day), diabetes mellitus, and history of pancreatitis were significant risk factors for pancreatic cancer. We found synergistic interactions between cigarette smoking and family history of pancreatic cancer (AOR 12.8, 95% confidence interval [CI] 1.6-108.9) and diabetes mellitus (AOR 9.3, 95% CI 2.0-44.1) in women, according to an additive model. Approximately 23%, 9%, 3%, and 5% of pancreatic cancer cases in this study were related to cigarette smoking, diabetes mellitus, heavy alcohol consumption, and family history of pancreatic cancer, respectively. CONCLUSIONS: The significant synergy between these risk factors suggests a common pathway for carcinogenesis of the pancreas. Determining the underlying mechanisms for such synergies may lead to the development of pancreatic cancer prevention strategies for high-risk individuals.     

Prostate cancer

In developed countries, prostate cancer is the second most frequently diagnosed cancer, and the third most common cause of death from cancer in men. Apart from age and ethnic origin, a positive family history is probably the strongest known risk factor. Clinically, prostate cancer is diagnosed as local or advanced, and treatments range from surveillance to radical local treatment or androgen-deprivation treatment. Androgen deprivation reduces symptoms in about 70-80% of patients with advanced prostate cancer, but most tumours relapse within 2 years to an incurable androgen-independent state. The recorded incidence of prostate cancer has substantially increased in the past two decades, probably because of the introduction of screening with prostate-specific antigen, the use of improved biopsy techniques for diagnosis, and increased public awareness. Trends in mortality from the disease are less clearcut. Mortality changes are not of the same magnitude as the changes in incidence, and in some countries mortality has been stable or even decreased. The disparity between reported incidence and mortality rates leads to the probable conclusion that only a small proportion of diagnosed low-risk prostate cancers will progress to life-threatening disease during the lifetime of the patient.     

Lebensstiländerungen zur Prävention koronarer Herzkrankheit

BACKGROUND: In developed countries arteriosclerosis is responsible for the majority of all deaths. With growing prosperity the life expectancy is increasing, and cardiovascular disease is becoming the primary cause of premature death. Most complications of arteriosclerosis occur unexpectedly. Because of the severe morbidity and high mortality prevention is the only true solution. CHANGES OF LIFESTYLE: Unhealthy nutrition, physical inactivity, overweight and smoking have been identified as the primary causes of arteriosclerotic vascular disease. Central obesity is responsible for the risk factors characterizing the metabolic syndrome. This is the result of inappropriate caloric intake and expenditure. In addition, the nutrients themselves can bear harmful consequences either indirectly by deteriorating risk factors like lipid parameters or by affecting directly the vessel wall. This can add to the deleterious effects of smoking. Evidently saturated fat is the single most decisive nutrient for atherosclerotic vascular disease. Cholesterol and trans fatty acids act additive, while unsaturated fatty acids appear to be beneficial. However, total fat intake is an important determinant of the energy supply, which again influences body weight and composite. Physical activity can counteract, but appears to be beneficial by several additional ways. Quitting smoking is highly effective already within few years. Together with physical activity and healthy nutrition more than 80% of all cardiovascular events can be prevented. CONCLUSION: Preventive medicine needs to focus on lifestyle changes because they are feasible and highly effective. A nutrition low in total fat primarily by avoiding saturated and trans fatty acids, but rich in carbohydrates and fiber is recommended. Daily physical activity in any preferred way should be encouraged, and quitting smoking needs to be strongly emphasized.     

Risikofaktor ?Rauchen“

Smoking is the most frequent cause of avoidable premature death. Annually, almost 6?million people die due to nicotine consumption. Comparing modifiable cardiovascular risk factors, smoking has the strongest impact on cardiovascular mortality. More than 50% of all premature myocardial infarctions are related to nicotine consumption. Even in patients with known coronary disease receiving optimal medical therapy, there is a remarkable additional preventive effect of smoking cessation detectable. Therefore, smoking cessation is an essential component of primary and secondary prevention strategies. Smoking cessation programs applying a combination of behavior therapy and supporting medical treatment have been demonstrated to be the most effective.     

Coronary artery disease in the developing world

Background

Coronary artery disease (CAD) is the leading cause of cardiovascular mortality worldwide, with >4.5 million deaths occurring in the developing world. Despite a recent decline in developed countries, both CAD mortality and the prevalence of CAD risk factors continue to rise rapidly in developing countries. The objectives of the current article are to review (1) the literature regarding CAD mortality and the prevalence of CAD risk factors in the developing world, and (2) prevention and control measures.

Methods

We conducted a MEDLINE search of the English language literature for the years 1990 to 2002 to identify articles pertaining to the prevalence of CAD in developing countries. The search was performed using the following key terms: coronary artery disease, developing countries, ischemic heart disease, incidence, prevalence, prevention and risk factors. We also obtained relevant statistical information from The World Health Organization's Internet database.

Results

There is a paucity of data regarding CAD and its prevalence in the developing world. However, it is projected that CAD mortality rates will double from 1990 to 2020, with approximately 82% of the increase attributable to the developing world. Existing data suggest that rapid socioeconomic growth in developing countries is increasing exposure to risk factors for CAD, such as diabetes, genetic factors, hypercholesterolemia, hypertension, and smoking. There is a relative lack of prevention and control measures to decrease exposure to these risk factors in developing countries.

Conclusion

Documented information on the prevalence of CAD in developing countries is sparse, but there is sufficient data to suggest an impending epidemic. Prevention and targeted control of risk factors for CAD could potentially reduce the impact of CAD in the developing world as it has in industrialized nations.