HIFU stands for High Intensity Focused Ultrasound which is another technique for treating prostate cancer. Ultrasound has been used for medical imaging (such as ante-natal scans) for decades, but recently the technology has been developed so that it can be used for treatment as well as diagnosis.
How is HIFU used to treat prostate cancer?
HIFU is focused onto a small area of diseased prostate treatment which does not involve an incision and instead involves precision focused ultrasound waves which raise the temperature of the target tissue to 80-90°C in two to three seconds, effectively destroying the targeted cancerous tissues.
Before the HIFU procedure?
A bowel preparation medicine is required on the day before the procedure. This can be taken in the comfort of your own home. Fasting before the procedure is not stenous. Patients are allowed to have a light breakfast followed by clear fluids for the rest of the day. You are allowed to drink water until 2 hours before admission. You will be admitted to hospital on the morning of the HIFU and immediately given an enema and any necessary procedures such as blood tests, an ECG or X-rays.
How is HIFU performed?
- First step: general anaesthetic.
- Second step: an ultrasound probe is placed in the rectum and the prostate is imaged.
- Third step: the same probe is then used to focus high-intensity sound waves on a particular area of the prostate, heating the diseased tissues and causing the cells to die.
- This process is repeated over the whole area of prostatic tumour until all the cancerous tissue has been destroyed.
- The surgery usually lasts between 1.5 – 4.5 hours.
After the procedure
When you wake up from the anaesthetic you will find that a trans-urethral or supra-pubic catheter has been left in place and will need to remain for the next 3-14 days. This is necessary as there will be swelling in the area which will impede your ability to pass urine.
- HIFU is ‘non-invasive’ – this means there is no surgery and no scars.
- HIFU can be carried out as a day case; you will be admitted for treatment early in the morning and will usually be able to leave hospital later the same day. Other more radical treatments usually require several days in hospital.
- Erectile dysfunction and incontinence are less likely than with other interventions.
Using this method of treatment some of the prostate tissue will remain untreated and will require active monitoring after the treatment. One possible side effect is that erectile dysfunction can occasionally occur in some men. Other side effects such as incontinence, urethral strictures, epididymitis and rectourethral fistulas are rare.
How does HIFU Compare with other Treatments?
As prostate cancer can be a disease that progresses very slowly, it is important to consider the outcome over a long period of time and, importantly, how much of a difference the treatment makes to survival. There are various ways to find out whether a treatment has been successful. Studies generally consider biochemical progression and some also carry out a prostate biopsy after treatment. To monitor ‘biochemical progression’ simply means asking ‘has the PSA gone up since treatment?’ A rise in PSA after treatment may indicate that the disease is still present.
It is also important to consider short and long term side effects: in the short term, the time that a patient stays in hospital and the risk of complications, and in the long term, the major issues are incontinence and impotence. Results available so far show that HIFU is effective at treating prostate cancer; one large study reports 92% of patients had a PSA of less than 1ng/ml (i.e. no biochemical progression) and 93% had negative prostate biopsies over the course of follow up (an average of 22 months). This is comparable with results for radical prostatectomy. Data so far suggests that approximately 20% of men will experience erectile dysfunction as a side effect of HIFU. However, the equipment and techniques have advanced since these figures were reported and it is expected that this will be lower when the new figures are released. Incontinence is seen in less than 1% of men.
Who can have HIFU?
We assess suitability for HIFU on an individual basis, but broadly speaking it is most suitable for patients with non-aggressive disease who fulfill the following criteria:
PSA < 15
- Prostate size < 40cc
- Gleason ≤7 (This is a measure of the aggression of the disease.)
- No evidence of metastatic disease (i.e. disease that has spread beyond the prostate)
You may not know all of these details about your condition. If you have had a prostate biopsy before, your urologist should be able to give you the relevant information. If not, we can arrange the appropriate tests for you.