FAQ on Prostate Cancer Cryotherapy

 

Overview

Cryotherapy (a.k.a. cryosurgery, cryoablation) is a minimally invasive technique that treats prostate cancer by freezing the prostate. Patients with prostate cancer localised to the prostate gland are suitable, even if they have been treated by radiotherapy before. The procedure is performed under general anaesthetic with overnight stay in hospital. A catheter to drain the bladder is needed for about 1 to 2 weeks afterwards. The procedure is tolerated reasonably well. Results are seem satisfactory. Side-effects can occur like all procedures for prostate cancer.

Why have cryotherapy for prostate cancer?

For people with localised treated or untreated prostate cancer who are seeking a minimally invasive treatment that is truely effective, but do not want or are unsuited for traditional surgery, laparoscopic or robotic prostatectomy, cryotherapy represents a good choice.

What are the advantages of cryotherapy for prostate cancer?

  • small holes in skin rather than a traditional large incision
  • short hospital stay (overnight stay)
  • low rate of complications
  • repeatable
  • minimal blood loss and very low chance of needing a blood transfusion
  • low chance of incontinence

How well does cryotherapy for prostate cancer work?

Using 3rd generation cryotherapy, samples have been taken 1 year after treatment. At this time, about 8% have evidence of prostate cancer still in their prostate and about 10% if radiotherapy has been given before. For patients who had prostate cancer outside the prostate at the time of cryotherapy, there is an about 25% chance of disease being present if biopsies are taken again 1 year after treatment. The lower the PSA after treatment, the greater the chance of cure. Overall, about 66% of men do not have an important rise in PSA after cryotherapy.

The best results occur in men PSA < 10 ng/ml, GS≤ 8, with localised prostate cancer (i.e. confined to the prostate), and who have not been treated before by radiotherapy.

What are the risks, side-effects or complications?

The following risks are possible:

  • Impotence: 80% of men who were potent before the treatment are affected by this . There may be some improvement after 2 years. In general, if impotence is unacceptable, another treatment should be chosen.
  • Incontinence: the chance of leaking urine or needing to wear pads in the underwear depends in part on the generation of cryotherapy. After 3rd generation cryotherapy, incontinence rates are about 3 to 4% (i.e. about 1 man in 25 men). Earlier forms of cryotherapy (2nd generation) had a 40% incontinence rates. Incontinence was more common if a TURP is necessary after cryotherapy. When very bad, another surgical operation may be required e.g. (insertion of an artificial urinary sphincter).
  • Passage of pieces of tissue in the urine: as freezing kills the prostate containing the tumour, dead pieces of tissue ('slough') may pass in the urine. Passage of slough may sometimes cause a temporary blockage in the flow of urine. This is usually transient.
  • Pain in the pelvis and rectum ('back passage'): about 1 in 10 to 1 in 20 men (5 to 10%) have pain felt in the back passage or deep in the abdomen. Usually, this passes after 4 weeks. After radiotherapy, pain is more common and 1 in 4 to 1 in 2 men (25 to 50%) may complain of pain. Treatment with nitrates may improve this.
  • Numbness in the Penis: 1 in 10 men (10%) have a numb penis after treatment because freezing can sometimes affect the nerves to the penis.
  • An abnormal connection between the rectum ('back passage') and the urethra ('water pipe'): this is properly known as a rectourethral fistula. It occurs if freezing damages the lining of the rectum and may affect up to 1 in 33 men (3%) having cryotherapy. It is more common after radiotherapy and may need treatment by a colostomy and prolonged catheterisation.
  • Urethral stricture: the urethra ('water pipe') may constrict and become narrow. This results in a poor flow of urine and may be treated by stretching.
  • Blockage of the ureteric orifices: freezing of the bladder near the prostate can damage the junction of the ureter (the tube from the kidney) with the bladder. This may need to be treated by a stent or occasionally by surgery.

What are the alternatives to cryotherapy?

The alternatives are:

  • Active monitoring: By actively monitoring the disease and intervening only when the disease is more aggressive, more people avoid the side-effects of treatment. However, the opportunity for cure may be lost if treatment is given when the prostate cancer appears to be more aggressive. Active monitoring is not usually recommended when prostate cancer is likely to be important in the life time of the man with it.
  • High Intensity Focused Ultrasound (HIFU): this is less invasive than cryotherapy as no skin incisions at all are made. People feel less tired after HIFU than cryotherapy. The treatment is effective according to the limited evidence available, however there is more uncertainty about the efficacy of this form of treatment compared to surgery, radiotherapy and cryotherapy. Impotence is much less common with this form of treatment compared to cryotherapy.
  • Brachytherapy: this is effective with published data to support it, but may be less effective than cryotherapy for high-risk prostate cancer. Needles need to be passed through the skin between the anus and rectum into the prostate like cryotherapy. The side-effect profile is similar to cryotherapy, but includes also the risk of radiotherapy. Impotence is much less common with this form of treatment compared to cryotherapy.
  • External beam radiotherapy: This is effective treatment for prostate cancer. Radiotherapy treatments are given daily for about 6 weeks or so. Most patients tolerate radiotherapy reasonably well although some may suffer with diarrhoea, bleeding from the back passage and blood in the stool. Sometimes, urinary symptoms are exacerbated. For people who are young having radiotherapy, there are sometimes long-term problems with radiotherapy affecting the structures around the prostate including the bladder, rectum and bowel.
  • Radical prostatectomy: this is possibly the most likely to prolong life compared to all treatments, but is also associated with the most side effects (incontinence, impotence and possible blood transfusion). The operation can be performed through a large incision in the lower abdomen using traditional techniques. Alternately, about 5 small incisions can be made and the prostate removed using keyhole laparoscopic techniques either with or without the aid of a robot. Keyhole techniques are less invasive, require a shorter hospital stay and are as successful as traditional surgery

Are any special tests required before cryotherapy?

A definite diagnosis of prostate cancer is necessary. The size of the prostate should be known and this is available usually from the transrectal ultrasound performed to obtain biopsies from the prostate.

How do you prepare before treatment by cryotherapy?

Preparation before cryotherapy depends in part on where the surgery is planned. In many places, it will be necessary to clear the bowel ('bowel prep'). This involves drinking fluids and having solutions to empty or clear the bowel the day before cryotherapy. On the day of cryotherapy, an enema is given in the morning, no food is allowed and no fluid is drunk 4 hours before the procedure.

How is cryotherapy for prostate cancer performed?

You are admitted to the hospital. Whilst asleep under general anaesthesia, your surgeon passes an ultrasound probe into the back passage (anus) to scan the prostate and then needles through the skin between the anus and scrotum into the prostate gland. Your bladder is drained with a special catheter that also warms the urethra (water pipe). The prostate is frozen, thawed, frozen once more and then thawed again whilst the surgeon monitors the process by ultrasound and temperature sensors. The anaesthetist wakes you up and a nurse takes you back to the ward.