The National Institute for Clinical Excellence is examining high-intensity focused ultrasound for prostate cancer and will publish guidance on its safety and efficacy to the NHS in England, Wales and Scotland. The Institute's Interventional Procedures Advisory Committee has considered the available evidence and the views of Specialist Advisors, who are consultants with knowledge of the procedure. The Advisory Committee has made provisional recommendations about high-intensity focused ultrasound for prostate cancer.

This document summarises the procedure and sets out the provisional recommendations made by the Advisory Committee. It has been prepared for public consultation. The Advisory Committee particularly welcomes:

• comments on the preliminary recommendation
• the identification of factual inaccuracies
• additional relevant evidence.

Note that this document is not the Institute's formal guidance on this procedure. The recommendations are provisional and may change after consultation.

The process that the Institute will follow after the consultation period ends is as follows:

• The Advisory Committee will meet again to consider the original evidence and its provisional recommendations in the light of the comments received during consultation.
• The Advisory Committee will then prepare draft guidance which will be the basis for the Institute's guidance on the use of the procedure in the NHS in England, Wales and Scotland.

For further details, see the Interventional Procedures Programme manual, which is available from the Institute's website (www.nice.org.uk/ipprogrammemanual).

Closing date for comments: 23 November 2004

Target date for publication of guidance: February 2005

Note that this document is not the Institute's guidance on this procedure. The recommendations are provisional and may change after consultation.

Current evidence on the safety and efficacy of high-intensity focused ultrasound (HIFU) for prostate cancer appears adequate to support the use of this procedure provided that the normal arrangements are in place for consent, audit and clinical governance

Most evidence on the efficacy of HIFU for prostate cancer relates to the reduction of prostate-specific antigen (PSA) levels and biopsy findings. The effects on quality of life and long-term survival remain uncertain. Clinicians should therefore ensure that patients understand the uncertainties and the alternative treatment options. Use of the Institute's Information for the Public is recommended

High-intensity focused ultrasound may be used to treat carcinoma of the prostate either as a primary or salvage therapy.

Treatment options depend on the stage of the cancer. Current primary treatments for localised prostate cancer include 'watchful waiting', radiotherapy and radical prostatectomy. Metastatic prostate cancer is usually treated with hormone therapy.

High-intensity frequency ultrasound for prostate cancer is carried out under a spinal or general anaesthetic. An endorectal probe incorporating an ultrasound scanner and a HIFU treatment applicator is inserted. The probe emits a beam of ultrasound, which is focused to reach a high intensity in the target area. Absorption of the ultrasound energy creates an increase in temperature, which destroys tissue. A cooling balloon surrounding the probe protects the rectal mucosa from the high temperature. A urethral or suprapubic catheter is used after the procedure.

The evidence was based on case series and the main outcomes reported were negative biopsy rates and PSA nadir levels. Some studies reported disease-free survival rates but the criteria used to define disease varied. A systematic review, including eight case series, reported a negative biopsy rate of 60% (37/62) in one study with follow-up not specified, and 80% (75/94) in a study with 3-year follow-up. In three further studies in the review, the proportion of patients without clinical or biochemical evidence of disease ranged from 56% (28/50) at 24 months to 66% (67/102) at 19 months.

Three additional case series reported negative biopsy rates between 87% (251/288) in a study with mean follow-up of 13 months and 93% (128/137) in a study with mean follow-up of 22.5 months. One of these studies, which included 146 patients, also reported disease-free survival rates of 54% or 71.5%, depending on the criteria used to define disease-free status. For more details, refer to the sources of evidence (see Appendix).

Urinary tract infections and stress incontinence were the most commonly reported complications, affecting between 4% (6/137) and 48% (46/96) and between 8% (9/111) and 23% (23/102) of patients in two case series. Rectourethral fistula was reported in between less than 1% (1/137) and 3% (3/111) of patients. Four studies reported rates of impotence after the procedure between 24% (75/315) and 100% (62/62) but the proportion of men who were potent before treatment was inadequately reported. Other complications included prolonged urinary retention, urge incontinence, urgency, bladder neck stenosis, urethral stenosis, urethritis, prostatic abscess, epididymitis, asymptomatic rectal burns and chronic pelvic pain. For more details, refer to the sources of evidence (see Appendix).

The Specialist Advisors listed urinary incontinence, rectal fistula, bowel perforation and erectile dysfunction as potential adverse events but noted that this procedure appears to be safer than alternative radical treatments for prostate cancer. Two Specialist Advisors noted that there were concerns regarding control of local heating and limiting sound energy to the target area.

The following document, which summarises the evidence, was considered by the Interventional Procedures Advisory Committee when making its provisional recommendations.

Interventional procedures overview of high-intensity focused ultrasound for prostate cancer, March 2004

Available from: www.nice.org.uk/ip230overview