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

Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. In cancer, some of the body’s cells begin to divide without stopping and spread into surrounding tissues. Cancer is also called malignancy. Cancer cells differ from normal cells in many ways that allow them to grow out of control and become invasive.

Normal cells mature into very distinct cell types with specific functions, cancer cells do not. This is one reason that, unlike normal cells, cancer cells continue to divide without stopping. Cancer can start almost anywhere in the human body, which is made up of trillions of cells. When cancer develops, however, this orderly process breaks down.

As cells become more and more abnormal, old or damaged cells survive when they should die, and new cells form when they are not needed.

These extra cells can divide without stopping and may form growths called tumors. All tumor cells show some specific characteristics. These characteristics are required to produce a malignant tumor. They include:

Cell growth and division absent the proper signals

Continuous growth and division even given contrary signals

Avoidance of programmed cell death

Limitless number of cell divisions

Promoting blood vessel construction

Invasion of tissue and formation of metastases

There are more than 100 types of cancer, including breast cancer, skin cancer, lung cancer, colon cancer, prostate cancer, and lymphoma. Many cancers form solid tumors, which are masses of tissue. Cancers of the blood, such as leukaemias, generally do not form solid tumors.

Cancerous tumors are malignant, which means they can spread into, or invade, nearby tissues. In addition, as these tumors grow, some cancer cells can break off and travel to distant places in the body through the blood or the lymph system and form new tumors far from the original tumor.

There are many different symptoms of cancer. The symptoms may depend on the kind of cancer. For example, a symptom of breast cancer is a lump in the breast.

A symptom of skin cancer is an abnormal-looking mole. Some of the general symptoms may be: unexplained weight loss, fatigue, blood in the stool or urine, lumps anywhere on the body, changes in skin appearance, etc.

No doubt, cancers are serious. We become horrified hearing the very name of cancer! Cancer may occur in any organ of the body and it is one of the common causes of human death across the globe.

Cancers are non-communicable diseases. There are a number of risk factors for the development of cancers. Some of the examples are:

Smoking cigarettes, including passive smoking: Overall, for those who smoke one pack a day, the chance of getting lung cancer is about 10 times greater than for nonsmokers. Cigarette smokers are also more likely than nonsmokers to develop oral cancer and cancers of the larynx, esophagus, pancreas, bladder, kidney, and cervix. Smoking may also increase the likelihood of developing cancers of the stomach, liver, colon, rectum and prostate.

Chewing betel-nut, especially with tobacco is favourable for development of oral and stomach cancers. The lime increases the chance of mouth, cheek and tongue cancer.

Eating foods that are poor in fibres and rich in fat: Diet poor in fibres may lead to cancer of colon and rectum. Some evidence suggests a link between a high-fat diet and certain cancers, such as cancers of the breast, colon, uterus, and prostate.

Drinking alcohol may cause cancer of liver, esophagus and stomach.

Taking less physical exercise.

Obesity or excess body weight may be associated with breast cancer, colon cancer.

Ultraviolet rays, X rays and other radiations: UV radiation from the sun causes premature aging of the skin and skin damage that can lead to skin cancer.

Some chemicals such as benzene {may lead to leukaemia}, arsenic, formaldehyde, aflatoxin {associated with liver cancer}.

Some viruses such as hepatitis B virus {hepatocellular carcinoma}, hepatitis C virus {hepatocellular carcinoma}, Human papilloma virus {cancer of cervix of uterus}, Epstein-Barr virus {nasopharyngeal carcinoma} and other microorganism like Helicobacter pylori {carcinoma of stomach}, Schistosoma haematobium {squamus cell carcinoma of urinary bladder}.

The genes one inherits from one’s parents as well as age, sex, and race can also be factors in the development of cancer.

Most of the diseases are preventable and definitely prevention is better than cure. Cancers may also be prevented if some measures are taken. The following measures may be beneficial:

Keeping body weight low but within normal limit. Waist circumference should not be more than 37 inches in case of males and 31.5 inches in case of females.

Keeping body fit and active. Regular exercise such as walking, jogging, bicycling, swimming for 30 minutes daily at a time or at 10 to 15 minutes spells will help prevent cancer.

Eating foods rich in fibres. These foods include fresh fruits and vegetables, whole-grain breads and cereals, pasta, rice, and beans. Varieties of fruits and vegetables are better.

Eating less beef and mutton as they contain much saturated fat. Chicken may be consumed instead.

Eating more fish. Fish oil consumption can delay or reduce tumor development in breast cancer as well as colon cancer.

Avoiding or quitting smoking cigarettes, including passive smoking.

Reducing intake of salty food and avoiding extra salt in food.

Breastfeeding baby for at least six months to reduce chances of breast cancer.

Avoiding drinking alcohol.

Avoiding direct sunlight

exposure.

If cancers are detected earlier at their incipient stages then they can be treated easily and effectively. Therefore, for early diagnosis routine screening for cancers is to be done.n