Cryotherapy is a procedure whereby tissue in the body is destroyed by the technique of freezing. The tissues are frozen to an extremely low temperature (-40 degrees Celsius) and cells inevitably undergo complete destruction. There have been many studies shown to prove this.
The first laparoscopic cases to be performed in the UK were performed by one of our top urologists Mr Christopher Anderson in December 2004. He has since accumulated a large personal series and remains an opinion leader in the UK, so who better to explain how cryotherapy works for early stage renal cancer than Mr Anderson himself.
What is cryotherapy?
In the context of renal cryotherapy, the tumour is punctured with needles, which are subsequently frozen with a view to destroying the cancer cells completely. The tumour becomes enveloped in an "ice ball" during the procedure. This results in both immediate and delayed tissue destruction. The tumour is frozen then thawed twice at the same sitting. In so doing the cells are destroyed (necrosis) in the short term and later the frozen tumour becomes scar tissue (fibrosis).
Cryotherapy is a relatively new treatment for early stage renal cancer and although international studies show very promising results there is only medium term follow up. This places the procedure in a category where one cannot comment on the long-term cancer control achieved. Therefore patients should be counselled about this so they are fully informed in making their choice of treatment.
Who is eligible for this treatment?
This method is only applicable to small renal lesions, usually below 4cm. It is ideally suited to people who have small renal tumours but who, for a clinical reason, are not able to be subjected to the metabolic demands of a larger open or laparoscopic/robotic operation in order to remove it.
Another group of patients would be those who have a single kidney with either single or multiple tumours. By targeting these lesions with needles one invariably only freezes the tumour cells and spares the surrounding normal renal tissue. It is therefore preferable for such cases as it is a procedure where as much normal renal tissue is spared. It is also ideal in someone who has impaired renal function as the impact of this treatment on renal function is negligible.
A final group in whom it has been shown to be successful is those who have a familial tendency to develop multiple renal tumours from a young age (particularly Von Hippel Lindau syndrome). These patients are likely to require multiple surgical attempts to remove their cancers over a lifetime and it is sensible to spare as much normal renal tissue from the start by using this minimally invasive technique.
How is it done?
The procedure is done as laparoscopically or percutaneously.
The laparoscopic approach is a minimally invasive procedure (keyhole surgery) undertaken by a urologist with the advantages of minimal post-operative pain and earlier return to normal activity.
The original technique used was hand-assisted laparoscopy, whereby an incision of a 6-7cm is made through the umbilicus allowing the insertion of the surgeon’s hand to help direct the needles. Subsequently, the pure laparoscopic approach was adopted. Here, 3 X 1 cm cuts on the skin surface are made through which the instruments are inserted. The procedure takes about two hours and is done under general anaesthetic.
The advantage of the laparoscopic approach is that the tumour can be seen well with unlikely damage to any surrounding organs as the whole procedure is done under vision.
Recently the percutaneous technique has become more popular. A radiologist performs this by passing the needles directly through the flank under X-ray imaging guidance (percutaneously). Usually, CT scan guidance is used but some centres might use MRI. It is extremely well tolerated by patients as it is the least invasive option, hence its popularity. Not all tumours are suitable though as they might be located in a position where it might be difficult for the needles to reach them percutaneously.
In both techniques, multiple needles are inserted into the tumour and by forcing pressurised Argon gas through the needles one is able to reduce the temperature at the tip of the needle to extremely low temperatures (-150 degrees Celsius). Passing pressurised Helium through them then thaws these needles.
Do not hesitate to book an appointment with Mr Anderson if you're interested in having cryotherapy.