As the world commemorates World Cancer Day today, February 4, 2016, here are a few facts you might not know about the disease.

1.  Cancer is the name given to a collection of related diseases. This is where some of the body’s cells begin to divide without stopping and spread into surrounding tissues.

Cancer can start almost anywhere in the human body, which is made up of trillions of cells.

The word ‘cancer’ comes from the Latin for 'crab.' It was first described by the ancient Egyptians.

In ancient days, doctors, when describing certain tumours which had veins or extensions from the main body, called them crab-like, or ‘cancerous’.

Around 1600 B.C., the earliest description of cancer was found in the Edwin Smith Papyrus document, which stated that cancer ''has no treatment''.

The document also described breast tumours removed by a tool called the fire drill.

2.  Not all cancers are hereditary. According to roche.com, only 5-10 percent of all cancers are hereditary. It says most cancers develop through a combination of hereditary and environmental factors, including obesity, smoking, alcohol and diet.

Meanwhile, several studies have indicated that there are more skin cancer cases due to indoor tanning than lung cancer cases due to smoking.

3.  Cancer is not a death sentence

Over half of all cancer cases, and up to half of all cancer deaths, are preventable, researchers believe. This means there are between 2.4 million and 3.7 million avoidable deaths per year, 80% of which occur in low- and middle-income countries.

There are about 28 million cancer survivors worldwide, due to the progress made in recent decades. More cancer patients in several countries are surviving than ever before.

4.  Breast cancer is more common in the left breast than the right

Scientists have indicated that the left breast is 5 - 10% more likely to develop cancer than the right breast. The left side of the body is also 10% more prone to melanoma (a type of skin cancer). Scientists are however yet to find out why.

5.  In coping with the disease, scientists have said that we should learn as much as we can about cancer and its treatment. You must learn to express your feelings,as hiding the feelings can make it harder to find good ways to deal with them. Try to talk with trusted friends or relatives, or keep a private journal. You can express your feelings through painting, drawing, or listening to music.

Don't forget to start a mild exercise program such as walking, yoga, swimming, or stretching. Such exercise can help you feel better.