In all, there are around 200 different types of cancer that can affect the human body. A large percentage of people will be affected by some form of cancer or other in their lifetime. Some types of cancer are more serious than others. Some can be treated more easily than others, and the survival rate varies among types.

There are two general categories of cancer. Carcinomas are cancers that develop on the surface linings of the organs. Sarcinomas are cancers that develop in the cells. Sarcinomas affect solid tissues such as muscle and bone. They can also develop in the blood vessels.

The human body is made up of tiny cells. Each of these cells contains genes. Proteins inside these genes regulate the division and multiplication of the cells. If a gene becomes damaged, the cells can continually grow and divide without stopping. If too many of these damaged cells form together, they can grow into a tumor.

Tumors can either be malignant or benign. Malignant tumors are the serious cancers. They can multiply and spread throughout the body's tissues and organs. Not all types of cancer form tumors. Cancers of the blood, such as leukemia, attack other areas of the body through the bloodstream.

Many of the causes of certain types of cancer are known. Contributing factors to cell damage include smoking, high exposure to the sun and an unhealthy diet. It has been proven that many types of cancer, such as breast cancer, are hereditary. There are also links between cancer and obesity or a lack of exercise.

The symptoms of cancer vary according to the form of the disease. The different types of cancer usually have a few common symptoms. These may include weight loss, lethargy and strange lumps or swellings. Cancer may also produce night sweats, fever and anaemia. These symptoms can all be caused by other illnesses, so it is important to consult a doctor as early as possible if you suffer from any of them.

The form of cancer treatment chosen will depend on how advanced the cancer is and the type of cancer present. There are three main types of cancer treatment. Surgery is used to remove solid tumors. This treatment is commonly used in the early stages of cancer.

Chemotherapy is used to treat various types of cancer using medication. Drugs are used to shrink tumors or kill cancerous cells. Radiotherapy consists of using radiation from x-rays to destroy cancerous cells. All three treatments have a higher success rate in reducing or killing cancer if the disease is caught early enough.