The kidneys are the main excretory organs of the body, filtering and cleaning the blood, removing toxins and making urine to eliminate these waste products from the body.

There are several types of cancer of the kidney, including Wilms’ tumour (a childhood cancer) and Transitional cell carcinoma of the renal pelvis. However, by far the most common is Renal cell cancer, also known as Renal cell carcinoma or hypernephroma.

Symptoms

The incidence of kidney cancer is increasing. The disease is usually characterised by one or more of the following symptoms:

• Passing of blood in the urine
•  Existence of a lump in the abdomen
• Back pain unrelated to any other cause
•  Weight loss
• Anaemia (a range of disorders affecting red blood cells).

Causes

Most kidney cancers are not inherited. Only 4% of cases of kidney cancer can be attributed to a family history of the disease.
Lifestyle choices such as a high-protein diet, obesity and smoking are risk factors in primary kidney cancer. Industrial chemicals such as asbestos, lead and cadmium have also been linked with the disease.
Some cases of cancer in the kidney occur as a result of tumours spreading from another site. These cases are called secondary kidney cancer.

Diagnosis

The initial diagnosis is normally made after a thorough medical examination including x-rays, blood tests and possibly other types of scan. The patient is likely to be referred to a hospital for consultations and treatment.

Kidney cancer is most common in men aged over 40 years. As back pain is a common ailment, it is sometimes not recognised as a symptom of kidney cancer in sufferers until the disease has spread beyond the affected organ. Therefore, it is important that people who have other symptoms of kidney cancer see their doctor as soon as possible for an examination.

Treatment

Treatment for kidney cancer usually begins with surgery to remove the tumour from the kidney, and in most cases the kidney itself, to prevent the cancer from spreading to other areas of the body. This operation is called a nephrectomy. In most cases, all normal renal functions can be performed by the remaining kidney.

Following surgery, other treatments may be offered. These will depend on the type and extent of the kidney cancer being treated, and may be given in combination to increase their effectiveness.

• Chemotherapy uses anti-cancer drugs to destroy cancer cells.
• Immunotherapy (also called biological treatment) uses agents derived from the immune system to help the body defend itself against or attack cancer cells.
• Hormone therapy involves the use of progesterone to attack cancer cells that have spread from the primary tumour site.
• Radiation is the use of high-energy waves directed at the tumour to destroy the cancer cells.

In some cases, for example when the cancer cannot be surgically removed or has spread elsewhere, a course of hormone therapy, radiotherapy or immunotherapy may be recommended instead.

Prevention

There is no evidence to suggest that radical changes in diet will prevent cancer occurring. However, a healthy, well-balanced diet, regular exercise and stopping smoking all help to maintain good health, and can be particularly important in strengthening the system of people already undergoing treatment for cancer.