What is kidney cancer?
Kidney cancer (renal cell cancer) is a malignant growth affecting a kidney. Cancer is a growth of abnormal cells that have the potential to spread elsewhere in the body.
What causes kidney cancer?
The exact cause of kidney cancer is unknown, and there are probably different causes for different people. We know that there are some risk factors that increase the chance of developing kidney cancer:
- Men are at higher risk than women
- Long term dialysis
- High blood pressure (may be associated with kidney cancer)
- Family history of kidney cancer in a first-degree relative
- A history of thyroid cancer
- Previous radiotherapy for testis cancer or cervical cancer
There are also a few rare genetic conditions that increase the risk:
- Von Hippel Lindau (VHL) syndrome
- Tuberous sclerosis
- Birt-Hogg Dubé syndrome
- Hereditary papillary renal cell cancer
Smoking is the greatest modifiable risk factor for kidney cancer. Your risk of kidney cancer will fall if you stop smoking. Along with obesity, these are two risk factors that you can control, and you should seek medical help to stop smoking and lose weight.
How is kidney cancer discovered?
This will vary from person to person. The most common way that kidney cancer is discovered is by chance on a CT or ultrasound scan done for another reason. These kind of tumours are called an 'incidental renal mass'. Some people may develop blood in the urine, which leads to investigations that discover a tumour on the kidney. Rarely kidney cancer may be discovered if a patient has pain in the side (loin) and blood in the urine
How is kidney cancer investigated?
When you are referred to a urologist, you may or may not need further investigations, depending on what you have had so far. You will need a consultation to take your history, and to discuss any other medical conditions, medications and allergies that you have. An examination will also be done as necessary. For a work-up of kidney cancer, you will generally need:
- A CT scan (with intravenous contrast)
- A Chest X-ray or a CT scan of the chest
- Blood tests
- Very occasionally, a Bone Scan
The aim of these investigations is to help to 'stage' the kidney cancer. Staging is a term used to describe how large the tumour is, and if there are any signs of spread, either near the kidney or to other organs. This is vital for planning treatment, as the possible treatments are dictated by staging.
Biopsy of a renal tumour (not always necessary)
In some circumstances a biopsy of the tumour can be very helpful in determining future treatment. If the kidney tumour is less than 3cm, 20-30% of them are benign and not malignant, and don't need any treatment. In other circumstances (for example a large tumour that may have spread), your Urologist needs to know exactly what kind of tumour it is, as it may best be managed by immunotherapy rather than surgery.
A biopsy is performed by a radiologist in an X-ray department, using CT or ultrasound to guide the biopsy. It is done as a day procedure with local anaesthetic. The tissue from the biopsy will be sent to a pathology laboratory for examination, and the results discussed with you at your follow-up appointment.
How is kidney cancer treated or managed?
The type of treatment that is best for you depends on a number of factors. The stage of the cancer (how large it is, and if it has spread anywhere else) and your medical history/other medical problems are of utmost importance in making the decision about treatment options. The treatment options are different for localised kidney cancer, locally advanced kidney cancer, and metastatic kidney cancer. Nick Brook will discuss this with you in detail when you see him.
1. Localised kidney cancer (not spread beyond the kidney)
This option may be suitable for you if you have a small kidney tumour, generally less than three centimetres (cm). Many studies suggest that these sorts of tumours, if discovered incidentally, have a very low chance of causing problems in the future (the figures are about a 3% risk of future problems). The chance of problems is, of course, partly dictated by how long you will live; this is where your age and your other medical conditions have a bearing on decisions. Therefore, active surveillance of a small kidney tumour may be particularly appropriate for older people. Surveillance involves regular scans (ultrasound or CT) to watch the tumour. If there are signs that it is growing, it may need treating, although this is relatively rare.
Before you start active surveillance, some urologists believe that a biopsy may be helpful. One of the reasons for this is that 20-30% of these tumours are benign and not cancer.
A partial nephrectomy involves an operation to remove the tumour from the kidney, leaving behind as much normal kidney as possible. Interestingly, this operation can be more involved, and have more possible short-term complications than completely removing the kidney.
The advantage of partial nephrectomy is that you are left with some functioning kidney tissue on the side of the tumour, rather than no kidney on that side. Whilst many people who have an entire kidney removed live completely normal lives, there may be some advantages to saving as much kidney tissue as possible, particularly if you have (or are at risk of developing in the future) conditions like diabetes, high blood pressure and obesity. These conditions can cause kidney damage.
The need for a partial nephrectomy or a complete (radical) nephrectomy will be discussed with you.
Complete (radical) nephrectomy
If the kidney tumour is large, or if partial nephrectomy would be difficult, with a high risk of complications, radical nephrectomy (removal of the entire kidney along with the tumour) may be the best option. This operation can be performed by keyhole (laparoscopic) or open surgery. The keyhole operation offers a quicker short-term recovery, with less pain early after the operation. Therefore, this is the preferred method if it is possible. If the tumour is very large or has spread beyond the capsule of the kidney, open surgery may be the best option.
Other options for treatment in patients unfit for surgery for kidney tumours
If you have medical problems that would make surgery unsafe, there are some other options for treatment. These are not 'standard' curative treatment options, but may offer a degree of control of the tumour growth.
Microwave ablation of kidney tumours
This technique was introduced into the Royal Adelaide Hospital for kidney tumours in 2013. It has been used for a number of years for liver tumours.
We do not know the long-term outcomes of this treatment for kidney tumours. The technique requires a general anaesthetic, but there is no major surgery. Instead, a small needle is passed into the tumour under CT guidance, and microwave energy is passed through the tip of the needle.
Depending on the size of the tumour, around 6 different needle positions are used to gradually kill off the tumour. The procedure lasts about 1.5 to 2 hours.
Recovery should be quite quick afterwards. It is important to note that there are still potential complications after the procedure, and that the long-term effect on cancer control is not fully known.
Microwave ablation is only suitable for patients with small renal tumours less than 4cm, who are unfit for other forms of surgery, and in whom active surveillance does not seem to be a good idea.
Stereotactic radiation treatment for kidney tumours
Again, this is a relatively new technique, and is not fully proven for its effectiveness in renal tumours. Essentially, high doses of radiation are delivered to the kidney, in an attempt to kill off the tumour. Special equipment is required, and patients are sent to the Peter MacCallum Cancer Centre in Melbourne for this treatment. This kind of radiotherapy has been used effectively for some time in brain and lung tumours, but we do not have long-term results in kidney tumours. The procedure does not require an anaesthetic.
Stereotactic radiation treatment is only suitable for kidney tumours in patients who are unfit for other forms of treatment, but the maximum size can be extended up to 10cm.
Nick Brook or another urologist can refer you to the FASTRACK Study at the Peter MacCallum Cancer Centre if you are suitable for this treatment.
2. Locally advanced kidney cancer (spread beyond the kidney, but not to distant organs)
This kind of tumour can be very challenging to treat with laparoscopic surgery, and it is common, if not invariable, to need an open complete nephrectomy. The tretament of this stage of tumour is more difficult, and has a higher complication rate, than treating localised kidney cancer. In some circumstances, if the tumour has spread along the main vein (vena cava), a combined surgical approach is needed involving a liver surgeon and a vascular surgeon, as well as your urological surgeon.
3. Metastatic kidney cancer (spread to other organs such as lung, bone or brain)
Metastatic kidney cancer means it has spread to other organs in the body. This stage of cancer is not curable, but it is possible to control the cancer for a length of time with certain drugs. This length of time is variable, and it is not possible to give accurate predications about responses to the drugs. There are some patients who seem to have good results, and the tumours remain stable for a number of years. However, this is not always the case.
Immunotherapy is used rather than chemotherapy, and the names of some of the drugs are:
The kind of drug used will depend on the type of tumour you have, and there are different sequences of drugs that are being researched. This means if one drug does not work or the tumour starts to grow again, another drug can be tried. However, many of the drugs are relatively new and may not be available everywhere.
In some situations, even though the kidney cancer has spread to other distant organs (such as the lungs), there may still be some benefit in removing the kidney. This is not curative, but there is some evidence to suggest that, in carefully selected patients, survival time can be increased if the kidney is removed and immunotherapy is given. This is called a 'cytoreductive nephrectomy'.
This surgery has higher risks of complications, and some patients who have it never recover well enough from surgery to go on to have their drug treatment. One of the reasons is that the kidney tumours in patients with metastatic disease tend to be large with a rich blood supply. Bleeding complications are common. So it needs to be very carefully considered. Patients need to be:
- Otherwise well
- Have good performance status (i.e. not be too affected by the cancer)
- Have small amounts of metastatic disease, and mostly only in the lung
Follow-up after kidney cancer treatment
Your follow up after treatment will depend on the type of treatment you have had and the findings on pathological examination if you have had surgery.
There are a number of different types of kidney cancer including:
- Clear Cell (the most common)
- Papillary Type 1 and Papillary Type2
- Multilocular Cystic
- and there are some other rare types
All of these types behave differently in their likelihood of coming back in the future.
As well as the type of tumour, the pathology report tells us:
- The pathological stage
- The grade (how aggressive the tumour looked)
- If there were negative margins
- The presence of necrosis in the tumour
You will be seen 2-6 weeks after surgery to see how you are recovering. After this, you will be reviewed at regular intervals with various combinations of blood tests, blood pressure checks (we usually ask your GP to do these), examination and occasional imaging (chest x-rays, ultrasound and/or CT scans). The intensity and the length of follow up will depend on the factors determined from the pathology report, outlined above.
Do you have a question about Kidney Cancer?
If you have a question regarding Kidney Cancer and you would like more information, please contact us.