What Is Cancer?

Cancer is a disease that takes multiple forms, but is generally defined by abnormal cell division in the body, and their subsequent invasion into other cells, spreading through the body and causing potentially fatal damage to the DNA structure. The mutated cells become malignant and the body will die if the cancer cannot be successfully treated. Some of the most common cancers are prostate in men and breast in women, while many cases involve lung and pancreatic cancer. However, cancer can infect virtually any part of the body. Cancer can be caused through genetic inheritance, environment or damage from alcohol, cigarettes and other drugs, as well as various other unique factors. It is often first diagnosed by an unusual swelling or swellings on the body, and can be treated with varying degrees of success depending on the patient's condition using chemotherapy, surgery, and immunotherapy. If cancer is detected in its early stages, it can be quickly treated, with the patient continuing to lead healthy lives. There are many organizations around the world dedicated to researching and providing support to those with cancer, including Cancer Research UK, the MacMillan Cancer Relief.

A tumour is an abnormal mass of tissues, the growth of which exceeds and is uncoordinated with that of normal tissues. This growth persists in the same excessive manner even after the cessation of the stimuli which evoke the change. Some tumours are benign or harmless, but cancer is a malignant tumour. A cancerous structure is often abnormal bearing no resemblance to the normal cells of a tissue or organ. It has the ugly potentials of rapid growth, invasion and destruction of adjacent structure, and metastasis (dissemination or spread) throughout the body leading to death. A few characteristic features of cancerous cells are: (a) cells are either many times larger than their neighbours or extremely small; (b) nuclear cytoplasmic ratio 1:1 instead of 1:4 or 1:6; (c) nuclear shape extremely variable; (d) large nucleoli present in nuclei; (e) a typical and bizarre mitotic figures (tri-polar, quadric-polar, or multi-polar spindles); (f) loss of specialised functional characteristics; and (g) dissemination / metastasis / spread into vital organs to disrupt their functions. Cancer may be caused by viruses, continuous friction or long exposures to UV light, heat, or contact with certain chemicals. Even cigarette-smoking increases the incidence of lung cancer.

Cancer is not a single disease. It includes more than 100 different diseases. They may affect any part of the body. But they have one thing in common. They are all caused by cells that are out of control.

All living things are made up of cells. An adult human body has about 30 trillion cells—that's 30,000,000,000,000! Cells reproduce (make more cells) by dividing in half. In an adult body, about 25 million cells divide every second. That's how the body heals itself.

Sometimes a cell goes out of control and divides over and over. And that's what cancer is—unhealthy cells, growing and reproducing out of control. These cells are said to be cancerous.