There are several types of kidney cancer. Renal cell carcinoma (RCC, also known as renal adenocarcinoma or hypernephroma) is the most common type in adults, responsible for approximately 80 per cent of cases. Renal cell carcinoma can be subdivided into a variety of types, including clear cell cancer (the most common type) and papillary cell cancer. All renal cancers may occur in a more aggressive form too, known as sarcomatoid type.
Transitional cell cancer accounts for 8 per cent of kidney tumours and is more similar to bladder cancer. Wilm’s Tumour is a type of kidney cancer found in children.
Kidney Cancer Symptoms
Many people with kidney cancer have no symptoms at first, especially when the cancer is small. But the affected kidney will become larger and in time, the tumour may grow through the wall of the kidney and invade nearby tissues and organs, such as the muscles around the spine, liver and nearby large blood vessels.
As the cancer develops, the following may occur:
- Blood in the urine, which is usually painless and may ‘come and go’ as the tumour bleeds (the first symptom in 60 per cent of cases)
- Pain in the back or side
- Swelling in the abdomen
- High blood pressure
- Feeling generally unwell or tired
- Loss of appetite
- Polycythaemia (too much blood in body) or anaemia (too little)
- Varicocele (tangled network of veins in the scrotum)
- Hip fracture, owing to spread of the cancer to bone
- Excessive hair growth in females
- Feeling thirsty
- Night sweats
- Severe weight loss
Kidney Cancer Causes and Risk Factors
Although kidney cancer is more common in men over the age of 60, many people develop it for no apparent reason. However, certain risk factors increase the chance of it developing, including:
- Smoking – doubles the risk of renal cell carcinoma
- Obesity, especially in women
- High blood pressure
- Family history of the disease
- Dialysis patients with cysts in their kidneys
- Long-term use of non-steroidal anti-inflamatory drugs (NSAIDs) such as ibuprofen
- Inherited disorders such as Von Hippel-Lindau disease (where about 40 per cent of people with the disease develop a renal cell carcinoma). In these inherited forms of renal cancer there are mutations in the genes, which suppress or control tumour formation
Kidney Cancer Diagnosis
Many kidney cancers are diagnosed before any symptoms develop, and are usually seen by chance when a scan or other investigation is done for another reason.
Typically, symptoms include blood in the urine combined with pain and weight loss. However, it’s important to keep in mind that there are many causes for blood in the urine, such as an infection or kidney stones.
The first step is often an ultrasound scan of the kidneys. A CT scan, which gives a more detailed view of sections of the body, may be used if there is doubt about the diagnosis or to assess if the cancer has spread. Other tests include an Intravenous Pyelogram (IVP), where dye is injected into the blood stream and followed on x-ray through the urinary system, and cystoscopy, where the inside of the bladder and urinary system are inspected with a tiny telescopic camera.
Kidney Cancer Treatments
Treatment of kidney cancer depends on the type of tumour and how far it has spread, as well as the person’s general health. A process known as staging is used in each case to assess these factors. Staging is important because it helps to predict how the cancer is likely to progress and which treatments are most appropriate.
As with most cancers these days, a team of specialists including doctors, nurses, radiologists, oncologists, radiotherapists and others get together to review all the test results and then recommend a schedule of suitable treatment, which may include surgery, chemotherapy, radiotherapy and other treatments. Some cancers, especially very small ones found by chance, may not cause problems for a long time and specialists may advise a policy of “watching and waiting” or active surveillance to monitor it.
Treatment Options for Kidney Cancer
Surgery to remove all (or part) of the affected kidney. This is the most common treatment and can be done as a keyhole operation in some cases. If the cancer is at an early stage and hasn’t spread, surgery alone may be enough to remove the tumour and cure the disease. If the cancer is very small, the surgeon may remove just the part of the kidney containing the tumour and leave as much normal tissue behind as possible. If the cancer has spread, surgery to remove the affected kidney may still be advised, often in addition to further surgery to remove a secondary kidney tumour (one which has spread to another part of the body).
Radiotherapy for Kidney Cancer
Radiotherapy may be advised to kill any cancerous cells left behind following an operation.
Cryotherapy for Kidney Cancer
The cancer cells are destroyed using a freezing probe (this is sometimes done under local anaesthetic).
Arterial Embolisation for Kidney Cancer
Arterial embolisation may be used instead of surgery, where the artery to the kidney tumour is blocked. The blood supply to the tumour is then cut off, causing the tumour cells to die.
Radiofrequency Ablation for Kidney Cancer
High frequency radiowaves heat the cancer cells and kills them.
Biological Therapies for Kidney Cancer
‘Biological’ therapies medications, such as: sunitinib, sorafenib, pazopanib, bevacizumab, and interferon-alpha are based on naturally-found cell signalling molecules. Some have improved the outlook prognosis for kidney cancer patients. They may be used to reduce the risk of cancer returning after surgery.
Chemotherapy for Kidney Cancer
Chemotherapy (or anti-cancer drugs) doesn’t work as well as it does for other types of cancer. Speak to your specialist about what may be best for you.
If a cure is not realistic, in some cases treatment aims to control the cancer, limiting the growth or spread so it progresses less rapidly. This may limit the amount of symptoms for some time.
Kidney Cancer Prognosis
If the cancer is confined to the kidney without spreading, and the patient is in otherwise good general health, the prognosis is usually good.
Stage 1 Kidney Cancer
In stage one, for example, where the cancer is no more than 7 cm in diameter and completely inside the kidney, more than 90 per cent of patients survive at least five years after diagnosis (if the tumour is less than 4 cm). So, surgical removal of an affected kidney in this situation gives a good chance of cure.
Stage 2 Kidney Cancer
In stage two (larger than 7cm diameter but still confined to the kidney), up to 75 per cent of people are well five years after the surgery. Once the tumour has spread to a nearby lymph node, survival rate of five years is up to 70 per cent.
Stage 3 and 4 Kidney Cancer
However, many people with kidney cancer are diagnosed when the cancer has already spread, so a cure is less likely. Survival rates vary considerably depending on the grade of the cancer, and how aggressive it is. However, treatment can often slow down the progression of the cancer, and improve symptoms and quality of life.