Risk Factors For Cancer

Risk Factors For Cancer Salwa Hassan Teama (M.D.)

Contents

Cancer

Cancer as a Genetic Disease

Cancer as a Global Health Problem

Risk Factor

Risk Factors For Cancer

Avoidable Cancer Risk

Cancer

Cancer is one of the most common and severe problems of clinical medicine.

Cancer is not a single disease but rather a name applied to a great variety of malignant tumor that are formed by the same basic process of uncontrolled growth.

Cancer has emerged as a major public health problem in developing countries for the first time, matching its effect in industrialized nations . This is a global problem.

Cancer begins in cells , , the building blocks that form tissues .

Normally, cells grow and divide to form new cells as the body needs them . When cells grow old, they die, and new cells take their place.

Sometimes, this orderly process goes wrong . New cells form when the body does not need them, and old cells do not die . These extra cells can form a mass of tissue called a growth or tumor.

Cancer

B enign tumors which are:

Self - limited in their growth

Do not invade or metastasize ( although some benign tumor types are capable of becoming malignant ).

Malignant neoplasm or tumor (cancer) : group of cells display

Excessive growth and divi sion without respect to normal limit.

Invasive , invade and destroy adjacent tissues , and sometimes

Distant metastasis spread to other locations in the body .

Cancer may affect people at all ages, even fetuses , but risk for the more common varieties tends to increase with age.

Early diagnosis and early treatment are vital, and identification of persons at increased risk of cancer before its development is an important objective of cancer research.

Cancer

The etiology of cancer is multifactorial , with genetic, environmental, medical, and lifestyle factors interacting to produce a given malignancy .

It is now believed that cancer is caused by genetic mutations most often, by a series of mutations.

Nearly all cancers are caused by abnormalities in the genetic material of the transformed cells. These abnormalities may be due to:

Inheritance , and thus present in all cells from birth. The heritability of cancers are usually affected by complex interactions between carcinogens and the host's genome or

Effects of carcinogens , such as tobacco smoke, radiation, chemicals , or infectious agents .

Error in DNA replication (randomly acquired).

Certain normal genes involved in cell growth, development, and differentiation can be converted into cancer - causing " oncogenes " by mutation . Other genes that normally prevent the uncontrolled growth of cells " suppressor " genes can also produce cancer if they are knocked out by genetic mutations.

Cancer as a Global Health Problem

In the year 2000, malignant tumors were responsible for 12 percent of the nearly 56 million deaths worldwide from all causes . In many countries, more than a quarter of deaths are attributable to cancer . In 2000, 5.3 million men and 4.7 million women developed a malignant tumor and altogether 6.2 million died from the disease .

The predicted sharp increase in new cases from 10 million new cases globally in 2000, to 15 million in 2020 will mainly be due to steadily ageing populations in both developed and developing countries and also to current trends in smoking prevalence and the growing adoption of unhealthy lifestyles.

Update : http:// www.who.int /topics/cancer/en /

Risk Factor

A risk factor is anything that increases a person's chance of getting a disease . Some risk factors can be changed, and others cannot . Risk factors for cancer can include a person's age, sex, and family medical history . Others are linked to cancer - causing factors in the environment . Still others are related to lifestyle choices such as tobacco and alcohol use, diet, and sun exposure.

Different cancers have different risk factors . For example, exposing skin to strong sunlight is a risk factor for skin cancer . Smoking is a risk factor for cancers of the lung, mouth, larynx ( voice box ) , bladder, kidney, and several other organs .

Old age

Unhealthy lifestyle ( Western lifestyle ), Poor diet, lack of physical activity, or being overweight .

Environmental factors, defined broadly to include tobacco use, diet, sunlight and infectious diseases.

Occupational carcinogens

Radiation

Family history of cancer (Genetic susceptibility)

Alcohol

Chemicals and other substance

e.g. Recommendation of hormones , estrogen alone or estrogen along with progestin to help control problems ( such as hot flashes, vaginal dryness, and thinning bones ) that may occur during menopause . However, studies show that menopausal hormone therapy may cause serious side effects . Hormones may increase the risk of breast cancer.

Certain viruses or bacteria may increase the risk of developing cancer.

Human papillomaviruses : HPV infection is the main cause of cervical cancer . It also may be a risk factor for other types of cancer.

Hepatitis B and hepatitis C viruses : Liver cancer can develop after many years of infection with hepatitis B or hepatitis C.

Human T - cell leukemia / lymphoma virus HTLV-1 : Infection with HTLV-1 increases a person's risk of lymphoma and leukemia.

Human immunodeficiency virus : HIV is the virus that causes AIDS . People who have HIV infection are at greater risk of cancer, such as lymphoma and a rare cancer called Kaposi's sarcoma .

Epstein - Barr virus : Infection with EBV has been linked to an increased risk of lymphoma.

Human herpesvirus 8 : This virus is a risk factor for Kaposi's sarcoma.

Helicobacter pylori : This bacterium can cause stomach ulcers . It also can cause stomach cancer and lymphoma in the stomach lining.

In the gastro - intestinal tract ( GIT ) , any chronic tissue damage with necrosis and regeneration carries an increased cancer risk, e . g . consumption of very hot beverages ( squamous cell carcinoma of the esophagus ) , gastro - oesophageal reflux ( adenocarcinoma of the esophagus ) , chronic gastritis induced by H . pylori infection ( stomach cancer ) , Crohn’s disease ( cancer of the small intestines ) and ulcerative colitis ( colon cancer).

Breast cancer risk factors include several factors : age; changes in hormone levels throughout life, such as age at first menstruation, number of pregnancies, and age at menopause; obesity; and physical activity . Also, women with a mother or sister who have had breast cancer are more likely to develop the disease.

Prostate cancer risk factors include : Older age ; more common among African - American men than among white men ; High - fat diet ; Men with a father or brother who have had prostate cancer are more likely to get it.

Risk Factor For Cancer

Having a healthy diet, being physically active, and maintaining a healthy weight may help reduce cancer risk .

Eat well : A healthy diet includes plenty of foods that are high in fiber, vitamins, and minerals . This includes whole - grain breads and cereals and 5 to 9 servings of fruits and vegetables every day . Also, a healthy diet means limiting foods high in fat ( such as butter, whole milk, fried foods, and red meat.

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Be active and maintain a healthy weight : Physical activity can help control your weight and reduce body fat . Moderate physical activity ( such as brisk walking ) for at least 30 minutes on 5 or more days each week is recommended .

The best possible prevention against cancer remains the avoidance of exposure to cancer - causing agents : this is called primary prevention ( e.g. tobacco, industrial carcinogens, etc ….).

Early detection of cancer : education to promote early diagnosis and screening .

G enetic testing . These tests can check for certain inherited gene changes that increase the chance of developing cancer .

Having a risk factor, or even several, does not mean that you will get the disease … ………..

Many of these risk factors can be avoided. Others, such as family history, cannot be avoided. People can protect themselves by staying away from known risk factors whenever possible.

References & Online Further Reading