WHAT IS CANCER?

Overview

The human’s body consists of millions of cells - the body’s basic building blocks. Normal cells divide and grow in an orderly way. They divide, grow when body needs them and die when they should. But sometimes this mechanism goes wrong and some cells start growing in an abnormal and uncontrolled way. They divide and grow when body does not need them and old cells don’t die. The extra cells form a mass of tissue called a growth or tumor.  It continues to grow and crowds out normal cells. It may spread to distant parts if the body through the lymphatic system or the blood stream and settle in new places, forming new tumors. Cancer that has spread in this way is called metastatic cancer.

But not all tumors are cancerous. Tumors can be benign or malignant.

Benign tumors are non-cancerous. They can often be removed and, in most cases, they do not come back. Cells in benign tumors do not spread to other parts of the body. Most important, benign tumors are rarely a life threat.

Malignant tumors are cancererous. Malignant tumors are abnormal and divide without control or order and destroy the tissue around them. Cancer cells can also break away from a malignant tumor and enter the bloodstream or lymphatic system.

Types of cancer

There are several main types of cancer.

Carcinoma is cancer that begins in the skin or in tissues that line or cover internal organs.

Sarcoma is cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue.

Leukemia is cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the bloodstream.

Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system.

Risk Factors

Lifestyle – tobacco smoking, bad diet (prevalence of animal and dairy products, containing saturated animal fat over low cholesterol food), lack of physical exercise, obesity.

Environment or workplace - exposure to ultraviolet (UV) radiation from the sun, or exposure to carcinogens (cancer-causing substances).

Heredity - some gene alterations are inherited from one or both parents or grandparents. However it does not necessarily mean that the person will develop cancer, it only means that he/she has the bigger chance of getting cancer.

There are other uncertain reasons of cancer origin, which scientists continue to examine and research.