All about Cancer

Cancer is a large group of diseases that can start in almost any organ or tissue of the body when abnormal cells grow uncontrollably, go beyond their usual boundaries to invade adjoining parts of the body and/or spread to other organs.

– WHO definition

Cancer is not contagious and often occurs due to a mix of hereditary and environmental factors. More than 200 different types of cancer exist. Most cancers are named after the organ or type of cell in which they originate. For example, cancer that starts in the cervix is called cervical cancer, and cancer that starts in basal cells of the skin is referred to as basal cell carcinoma.

All cancers originate from cells, the body's basic units of life. The human body is composed of about 100 trillion cells. Cells keep the body healthy by growing, dividing, and producing new cells when the body needs them. Normally, when cells become old or damaged, they die, and new cells replace them. However, this process may be disrupted when cells divide and replicate uncontrollably, even if new cells are not needed by the body. This unnecessary cell growth may be the result of mutated or damaged genetic material. When this type of cell growth occurs, the result is an unneeded increase in the overall quantity of cells in the body. This increase in new cells can form a mass of tissue called a tumor. However, not all tumors are cancerous.

Tumors can be grouped into two categories.

Benign: These tumors are not cancerous and are rarely life-threatening. Often, they can be removed. Regrowth of the tumors after removal is not common. These cells do not spread to other parts of the body.

Malignant: These tumors are cancerous. Malignant cells can attack nearby healthy tissues. These cells also have the ability to metastasize or spread to other parts of the body. Some cancers do not form tumors. Leukemia, a cancer of the Bone marrow and blood, is a common example for such a cancer.

Cancers that originate in epithelial tissues (e.g. skin, tissues that line or cover internal organs.)

Cancers that originate in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue.

Cancers that originate in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue.

Cancers that originate in the cells of the immune system.

Cancers that originate in the tissues of the brain and spinal cord.

The most prevalent types of cancer in Sri Lanka are:

Cancer that originates in the tissues of the breast

Cancer that originates in the mouth and throat.

Cancer that originates in the cecum, ascending colon, transverse colon, descending colon, sigmoid colon and rectum.

Cancer that originates in the esophagus, the muscular tube that moves substances, such as food and water, from the mouth to the stomach.

Cancer that originates in the thyroid gland. This is the 2nd most common cancer among women in Sri Lanka.

Cancer that originates in the cervix, the lower part of the womb in a female's reproductive system.

Cancer originating in the prostate, a gland in the male reproductive system.

Cancer that originates in the tissues of the lungs.

Cancer that originates in the ovaries, the female reproductive organs that produces eggs.