Cancer: Prevention

To prevent tumor diseases (cancers), attention must be paid to reducing individual risk factors. Behavioral risks

  • Diet
    • High total fat intake is associated with increased incidence of breast carcinoma, colorectal carcinoma, prostate carcinoma, and endometrial carcinoma (cancer of the breast, colon, rectum, prostate, and uterus).
    • Numerous studies show that people who eat a diet low in meat and sausage are less likely to develop malignant tumors. This is mainly attributed to the fact that a predominantly ovo-lacto-vegetarian diet provides more micronutrients and bioactive substances that have an anticarcinogenic (cancer-inhibiting) effect, as well as a lot of fiber.
    • Smoked and cured foods and foods rich in nitrates and nitrites.
      • Benzpyrene is produced during toasting and charcoal grilling. It is considered a risk factor for stomach and pancreatic cancer. It is found in all grilled, smoked, or burned foods. Cigarette smoke also contains benzpyrene, which in turn can lead to lung cancer.
      • Nitrate is a potentially toxic compound: Nitrate is reduced to nitrite in the body by bacteria (saliva/stomach). Nitrite is a reactive oxidant that reacts preferentially with the blood pigment hemoglobin, converting it to methemoglobin. Furthermore, nitrites (also contained in cured sausage and meat products and ripened cheese) form nitrosamines with secondary amines (contained in meat and sausage products, cheese and fish), which have genotoxic and mutagenic effects. They promote the development of esophageal carcinoma, gastric carcinoma, pancreatic carcinoma and liver carcinoma (cancer of the esophagus, stomach, pancreas and liver). The daily intake of nitrate is usually about 70% from the consumption of vegetables (lamb’s lettuce, lettuce, green, white and Chinese cabbage, kohlrabi, spinach, radish, radish, beet), 20% from drinking water (nitrogen fertilizer) and 10% from meat and meat products and fish.
    • Avoid foods with:
      • Acrylamide (Group 2A carcinogen) – is metabolically activated to glycidamide, a genotoxic metabolite; an association between exposure to acrylamide and risk of estrogen receptor-positive breast cancer has been demonstrated. Acrylamide is formed when starches are overheated, i.e., during baking, frying, roasting, grilling, and deep-frying. When foods containing potatoes and cereals are heated dry above 180 °C, a particularly large amount of acrylamide is formed. Crispbread, French fries, potato chips, but also coffee, contain high amounts of acrylamide.
      • Aflatoxins are formed by molds and promote the development of liver tumors, esophageal cancer (esophageal carcinoma) and stomach cancer (gastric carcinoma). Aflatoxins are found in all moldy foods, e.g., moldy cereals, bread, and fruit. Corn production in the USA or in tropical countries is particularly affected. The aflatoxin content is often particularly high in peanuts, but also in hazelnuts and Brazil nuts as well as pistachios and almonds. Also repeatedly contaminated with aflatoxins are dried fruits, especially figs and numerous spices such as chili, paprika, bell pepper, nutmeg, ginger or turmeric.
    • A negative correlation exists between fruit/vegetable consumption and lung, breast, oral cavity, colon, prostate, cervical and bladder cancers.
    • Dietary fiber protects against colorectal cancer (colon and rectal cancer).
    • High salt consumption
  • Consumption of stimulants
  • Physical activity
    • Low physical activity
    • Sitting for long periods of time – those who spend most of their time sitting have a 50% increased risk of dying from cancer.
  • Psycho-social situation
    • High work stress: + 24% bronchial carcinoma (lung cancer), + 36% colorectal carcinoma (carcinomas of the colon (large intestine) and rectum (rectum)), + 112% esophageal carcinoma (cancer of the esophagus).
    • Night duty (cancer risk: + 19 percent).
    • Weekly working time > 52 hours
  • Pregnancy/breastfeeding
    • Late first pregnancy – after age 30 – circa threefold increased risk of mammary carcinoma (breast cancer).
    • Short breastfeeding period – the shorter the breastfeeding period, the higher the risk of developing breast cancer. This revealed a meta-study
  • Overweight (BMI ≥ 25; obesity) – increased body weight and energy intake are risk factors for breast, colon, prostate, endometrial, cervical, kidney, and thyroid cancers.
  • Android body fat distribution, that is, abdominal/visceral, truncal, central body fat (apple type) – there is a high waist circumference or waist-to-hip ratio (THQ; waist-to-hip ratio (WHR)) – for example, in breast and prostate cancer (breast and prostate cancer).

Drugs

  • Estrogen therapy – e.g., hormone replacement therapy for more than five years increases breast cancer risk.
  • Testosterone therapy – promoter of a prostate cancer.
  • According to the current state of science, oral contraceptives (birth control pills) increase the risk of developing breast cancer (mammary carcinoma) – not yet fully scientifically researched – only by a factor of 1.2 to 1.5 when taken for more than five years
  • Some cytostatic drugs increase the risk of a second tumor
  • “Iron overload” – Unbound free iron has a cytotoxic effect, meaning it damages cells. Iron is also discussed as a prooxidant in connection with the development of cardiovascular diseases – such as coronary heart disease (CHD; disease of the coronary vessels) resulting in myocardial infarction (heart attack) – and neurodegenerative diseases – for example, Alzheimer’s disease or Parkinson’s disease – and as a promoter of tumor diseases. The underlying mechanism is thought to be that iron promotes oxidative stress via its key catalytic function in the formation of cytotoxic oxygen and hydroxyl radicals, for example in the course of Fenton and Haber-Weiss reactions. Individuals suffering from hemochromatosis (iron storage disease), for example, have an increased risk of liver cell cancer. In addition, a study from the United States showed that elevated serum iron levels are associated with an increased risk of tumor disease.

Radiation exposure

  • Occurrence of malignant soft tissue tumors (sarcomas) after previous radiotherapy (radiotherapy).
  • Exposure to ionizing radiation
    • Computed tomography (CT) in childhood – CNS tumors (risk: 1.35-fold); leukemias risk: 1.72-fold).
    • UV radiation (including solarium use) – actinic keratosis (precancerous lesion; risk factor for squamous cell carcinoma), squamous cell carcinoma of the skin, basal cell carcinoma (BCC; basal cell carcinoma; 10 times more common than malignant melanoma), malignant melanoma
    • Radiotherapy/radiotherapy (e.g., for Hodgkin’s disease, prostate cancer).
    • X-ray or gamma radiation – bronchial carcinoma (radon! ), mammary carcinoma (breast cancer), leukemia, thyroid carcinoma.

Environmental pollution – intoxications

  • Inhalation of coal dust (miners) – bronchial carcinoma (lung cancer).
  • Carcinogens such as:
    • Aromatic amines (such as aniline, toluidine, naphthylamine, etc. and their derivatives; starting material for drugs, plastics, pesticides or dyes) – Urinary bladder carcinoma (cancer of the urinary bladder; bladder cancer).
    • Asbestos – lung cancer; laryngeal carcinoma (cancer of the larynx); pleural mesothelioma (a malignant (malignant) tumor of the pleura, i.e., the pleura, originating from the mesothelial cells (celomic epithelium); peritoneal mesothelioma (a malignant (malignant) tumor of the peritoneum, i.e., the peritoneum, originating from the mesothelial cells (celomic epithelium))
    • Arsenic – (skin, liver, lungs) – latency period 15-20 years.
    • Benzene – leukemia (blood cancer).
    • Benzpyrene- is found in exhaust fumes, smoke and tar. It is considered a risk factor for gastric cancer (stomach cancer) and prostate cancer (pancreatic cancer).Cigarette smoke also contains benzpyrene, which in turn can lead to bronchial carcinoma (lung cancer) and laryngeal carcinoma (cancer of the larynx).
    • Cadmium – prostate cancer (prostate cancer).
    • Chromium (VI) compounds – liver tumors, unspecified.
    • Nickel – bronchial carcinoma (lung cancer) and tumors of the internal nose and sinuses.
    • Chlorinated hydrocarbons (CHCs) – a group of organic chemical compounds in which particularly dangerous environmental pollutants are represented. Areas of application: Wood preservatives, cleaning agents, solvents and pesticides, plasticizers in paints and plastics, as well as for plastic production. Under unfavorable combustion conditions, other, partly toxic CHCs such as dioxins are formed.
    • Polycyclic aromatic hydrocarbons (PAHs; benzpyrene, benzanthracene, methylcholanthrene) – benzpyrene is considered a risk factor for gastric carcinoma (stomach cancer) and prostate carcinoma (pancreatic cancer). Cigarette smoke also contains benzpyrene, which in turn can lead to bronchial carcinoma (lung cancer) and laryngeal carcinoma (cancer of the larynx).
    • Polycyclic hydrocarbons (PAHs, contained in diesel exhaust; excretion of PAH metabolites via the kidneys) – risk factor for bronchial carcinoma (lung cancer) and urothelial carcinoma (cancer of the transitional tissue (urothelium) lining the urinary tract).
    • Indoor radon – bronchial carcinoma (lung cancer), malignant melanoma.
  • Contact with
    • Benzo(a)pyrene (1,2-benzpyrene) contained in soot (chimney sweep) – Testicular carcinoma (testicular cancer).
    • In tar and bitumen – bronchial carcinoma (lung cancer); laryngeal carcinoma (cancer of the larynx).
    • Lignite tars (lignite workers) – skin tumors.
    • Fine dust – bronchial carcinoma (lung cancer).
    • Fuchsin – urinary bladder carcinoma (bladder cancer).
    • Halogenated ethers (“haloethers”), especially dichlorodimethyl ether – bronchial carcinoma (lung cancer).
    • Wood dust – tumors of the inner nose and sinuses.

Other risk factors

  • Free radicals – these react, among other things, with the cell nucleus and the genetic information (DNA). The result of this oxidative DNA damage are, for example, point mutations and enzyme disorders, which lead to significant disruption of cellular functions and thus metabolic processes. ROS-related mutations (ROS = reactive oxygen derivatives) also increase with age. This affects in particular the mitochondria

Prevention factors (protective factors)

  • Number of children: parents in families with many children are less likely to develop cancer. This is true for:
    • Mammary carcinoma (breast cancer), endometrial carcinoma (cancer of the endometrium) and ovarian carcinoma (ovarian cancer) due toreduced number of ovulations (ovulation) and the associated lower exposure to estrogens, as well as oxytocin secretion after the birth of the child.
    • Brain tumors, bladder, bronchial (lung), stomach, skin and colon (large intestine) cancer, and for cancers as a whole.
  • Diet: consumption of a handful of nuts (cashews, hazelnuts, almonds, pecans, pistachios, walnuts) a day led to a cancer risk reduction of 15%.The health-promoting effect of nuts is probably due to the increase in activity of the protective enzymes catalase and superoxide dismutase, which activate the body’s defenses to detoxify reactive oxygen species.
  • Green tea – Studies of gastric cancer (stomach cancer) incidence show that flavonoids inhibit the growth of gastric cancer cells. Since especially in the regions of China and Japan is traditionally drunk a lot of green tea, there both men and women showed a fivefold lower mortality rate from gastric cancer than the average population A high intake of flavonoids in the form of green tea causes humans to have a lower risk of developing stomach cancer, colon cancer (colon and rectal cancer) and breast cancer (breast cancer). Notice. Patients treated with bortezomib (cytostatic drug) should not drink green tea or avoid EGCG products (epigallocatechin-3-gallate) to be on the safe side, because it can not be ruled out that the effect of bortezomib is affected.
  • Not smoking, low alcohol (≤1 drink/d for women, ≤2 drinks/d for men), not being overweight (18.5-27.5), and getting plenty of exercise can reduce cancer incidence by up to 70% and halve mortality by at least 50%.
  • Sports
    • Physically very active people have a lower risk of colon cancer (cancer of the colon and rectum).
    • Risk reduction for hormone-dependent breast carcinomas (breast cancer) is estimated at 30% (circa two hours of walking and one hour of cycling a day).
    • Women with colorectal cancer/cancer of the colon (colon) or rectum (rectum) (stage I to III) – at least 18 hours of weekly exercise (“metabolic equivalent test”) resulted in a highly significant improvement in survival in non-metastatic colorectal cancer.
    • Physical activity (at least 60 minutes of light exercise) in men reduces tumor incidence (12%↓) and survival (30 minutes reduces mortality by 33%) in the event of disease Conclusion: the more exercise, the higher the risk reduction. A minimum of 30 minutes of fast walking, jogging, or cycling is recommended at least five days a week (45 to 60 minutes is better). Other sports such as swimming or cross-country skiing are also suitable.
  • Sun protection for skin cancer prophylaxis, ie avoiding acute and chronic UV damage – due toactinic keratosis (cancer precursor; risk factor for squamous cell carcinoma), squamous cell carcinoma of the skin), basal cell carcinoma (basal cell carcinoma; 10 times more common than melanoma), melanoma.
  • Vitamin K antagonists (VKA) – risk reduction of 16% for new cancer; mammary carcinoma (breast cancer) 10%, bronchial carcinoma (lung cancer) 20%, prostate carcinoma (prostate cancer) 31%; chemoprotective effect of warfarin possibly because the drug inhibits the signaling pathway (GAS6-AXL) that promotes tumorigenesis independently of the anticoagulant effects