What Affects Oncology

Genetics is the single biggest factor affecting oncology, as mutations in genes such as TP53 and BRCA1 increase the risk of cancer development by 50-80% (National Cancer Institute).

Main Factors

• Smoking — the specific mechanism is the introduction of carcinogens into the lungs, which increases the risk of lung cancer by 15-30% (Centers for Disease Control and Prevention), with an estimated 80-90% of lung cancer deaths attributed to smoking (American Cancer Society). For example, a smoker who consumes 20 cigarettes per day has a 30% higher risk of developing lung cancer compared to a non-smoker.
• Obesity — the specific mechanism is the increased production of hormones such as insulin and estrogen, which increases the risk of breast, colon, and kidney cancers by 10-20% (World Health Organization), with an estimated 3.5% of all cancer cases in the United States attributed to obesity (National Cancer Institute). For instance, a person with a body mass index (BMI) of 30 or higher has a 20% higher risk of developing breast cancer compared to a person with a BMI of 25 or lower.
• Radiation exposure — the specific mechanism is the damage to DNA caused by ionizing radiation, which increases the risk of cancer by 5-15% (National Institute of Environmental Health Sciences), with an estimated 0.5-1.0% of all cancer cases in the United States attributed to radiation exposure (National Cancer Institute). For example, a person who receives a dose of 100 millisieverts (mSv) of radiation has a 5% higher risk of developing cancer compared to a person who receives a dose of 10 mSv.
• Viral infections — the specific mechanism is the introduction of viral oncogenes, which increases the risk of cancer by 5-10% (Centers for Disease Control and Prevention), with an estimated 15-20% of all cancer cases worldwide attributed to viral infections (World Health Organization). For instance, a person infected with human papillomavirus (HPV) has a 10% higher risk of developing cervical cancer compared to a person who is not infected.
• Air pollution — the specific mechanism is the introduction of carcinogens into the lungs, which increases the risk of lung cancer by 5-10% (World Health Organization), with an estimated 1-2% of all cancer cases worldwide attributed to air pollution (International Agency for Research on Cancer). For example, a person living in a city with high levels of particulate matter (PM2.5) has a 5% higher risk of developing lung cancer compared to a person living in a city with low levels of PM2.5.
• Diet — the specific mechanism is the introduction of carcinogens and mutagens into the body, which increases the risk of cancer by 5-10% (National Cancer Institute), with an estimated 5-10% of all cancer cases in the United States attributed to diet (American Cancer Society). For instance, a person who consumes a diet high in processed meat has a 10% higher risk of developing colon cancer compared to a person who consumes a diet low in processed meat.

How They Interact

The interaction between smoking and air pollution amplifies the risk of lung cancer, as the combination of carcinogens from tobacco smoke and air pollution increases the risk of lung cancer by 20-40% (International Agency for Research on Cancer). For example, a person who smokes and lives in a city with high levels of PM2.5 has a 30% higher risk of developing lung cancer compared to a person who smokes but lives in a city with low levels of PM2.5. The interaction between obesity and diet also amplifies the risk of cancer, as the combination of excess body weight and a diet high in processed meat increases the risk of colon cancer by 20-30% (National Cancer Institute). For instance, a person who is obese and consumes a diet high in processed meat has a 25% higher risk of developing colon cancer compared to a person who is not obese and consumes a diet low in processed meat.

Controllable vs Uncontrollable

The controllable factors affecting oncology include smoking, diet, and physical activity, which can be controlled by individuals through lifestyle changes. For example, quitting smoking can reduce the risk of lung cancer by 30-50% (Centers for Disease Control and Prevention), while consuming a diet high in fruits and vegetables can reduce the risk of colon cancer by 10-20% (National Cancer Institute). The uncontrollable factors include genetics, radiation exposure, and air pollution, which are determined by factors such as family history, geographic location, and environmental conditions. However, individuals can still take steps to reduce their exposure to these factors, such as wearing protective clothing and masks to reduce radiation exposure and air pollution.