What is kidney cancer?
Kidney cancer is a malignant cell growth (a tumour) in the kidneys. Its medical name is renal cell carcinoma. A tumour in the kidney can also be benign.
Kidney cancer is a general term. There are many variations of tumours in the kidney and stages of the disease. Your treatment and experience depend on the specific characteristics of the tumour and the expertise of your medical team.
The sections in this series provide general information about kidney cancer, diagnosis, and treatment options. Discuss your individual situation with your doctor.
What is the function of the kidneys?
The kidneys are two bean-shaped organs in the back of the abdomen which filter your blood and produce urine. They are important for various processes in the body, including regulating your blood pressure, the production of blood cells, and keeping your bones healthy (Fig. 1).
Fig 1: A kidney and its surrounding tissue, veins, and arteries.
Kidney cancer represents around 2% of all cancer diagnoses worldwide. In the last twenty years the number of cases of kidney cancer in Europe has increased slightly, but the survival rate has also gone up in most of the region. Because of the more frequent use and improvements in ultrasound and CT imaging technology, more kidney cancers are now diagnosed at an earlier stage.
Men are more likely to be diagnosed with kidney cancer than women. Most people are diagnosed between the ages of 60 and 70.
Stages of the disease
There are different stages of kidney cancer. If the tumour is limited to the kidney and has not spread, this is called
localized kidney cancer. In
locally-advanced kidney cancer, the tumour has grown out of the kidneys into surrounding tissue and invaded veins, the adrenal gland, or lymph nodes. Doctors speak of
metastatic disease if the cancer has spread either to distant lymph nodes or other organs.
Risk factors for kidney cancer
The causes of kidney cancer are often difficult to determine. General risk factors are smoking and obesity.
Having a first-degree relative with kidney cancer or high blood pressure are also potential risk factors. Certain lifestyle changes, most importantly quitting smoking and keeping a healthy weight, may reduce the risk of developing kidney cancer.
Localized Kidney Cancer
If you are diagnosed with localized kidney cancer, your doctor can recommend treating the cancer with partial nephrectomy, radical nephrectomy, active surveillance, radiofrequency ablation, or cryotherapy. Each procedure has its own advantages and disadvantages. The choice of treatment depends on your individual situation.
This section describes the different treatment options, which you should discuss with your doctor.
This is general information which is not specified to your individual needs. Keep in mind that situations can vary in different countries.
What is localized kidney cancer?
Localized kidney cancer refers to a tumour which is limited to the kidney and has not extended to other parts of your body. It may be a stage I or II tumour, depending on its size (Fig 1 and 2).
Fig 1: A stage I kidney tumour is a tumour up to 7 cm, limited to the kidney.
Fig. 2: Stage II tumours are still limited to the kidney but are larger than 7 cm.
Treatment options
The best option for the treatment of a kidney tumour is surgical removal. Localized kidney cancer can be removed through either partial nephrectomy or radical nephrectomy. Both procedures can be performed by open or laparoscopic surgery. Laparoscopic surgery can also be done with the aid of a surgical robot system.
During a partial nephrectomy only the tumour is removed, leaving the healthy kidney tissue untouched. This surgery is recommended whenever possible. If it is not possible to remove the whole tumour and leave part of the kidney intact, your doctor will recommend radical nephrectomy. This means that the kidney in which the tumour is located and the surrounding tissue are completely removed.
Sometimes, surgery may not be the best option for you. This may be because of your age or medical condition, for example. If the tumour is smaller than 4 cm, your doctor may suggest a period of active surveillance. During active surveillance, your doctor schedules regular visits to monitor the tumour. If the tumour continues to grow you may need further treatment. A good option in this case may be ablation therapy.
Ablation therapy can be either radiofrequency ablation (RFA) or cryotherapy. The aim of these procedures is to kill tumour cells by heating (RFA) or freezing (cryotherapy).
These are some topics you should discuss with your doctor when planning your treatment pathway:
Your medical history
If there are any cases of kidney cancer in your family
What to consider if you only have one kidney
Whether your kidney function is normal or if it has already been affected by other conditions like diabetes or high blood pressure
Whether you have a tumour in one or both of your kidneys
The kind of treatment available at your hospital
The expertise of your doctor. Ask your doctor about his or her experience with the recommended treatment option
Your personal preferences and values
Support during and after treatment
Terms your doctor may use:
Nephron-sparing surgery → Another name for partial nephrectomy
Open surgery → A surgical procedure in which the surgeon cuts skin and tissue to have direct access to the kidney
Laparoscopic surgery → A minimally-invasive surgical technique in which the surgeon does not need to cut through skin and tissue. Instead, the surgeon inserts the surgical instruments through small incisions in your abdomen
Surgical robot system → An instrument to help doctors perform laparoscopic surgery. The surgeon controls the robotic instrument with remote control sensors
