A treatment that uses sound waves to blast away prostate tumours has been proven to cure as many men of the disease as surgery that removes the gland - while causing significantly fewer side effects.
Until now the new procedure, called high-intensity focused ultrasound (HIFU), has been considered experimental. This has meant that the majority of British men diagnosed with the condition - who include former Rolling Stone Bill Wyman - are offered the more invasive operation called radical prostatectomy, which has a clear track record despite the risk of impotence and incontinence.
But a landmark study to be announced at the European Association of Urology annual meeting in Munich tomorrow has revealed that focal HIFU, which targets only the tumour while preserving the healthy prostate tissue around it, offers a 93 per cent recurrence-free survival rate at five years, putting it on a par with prostatectomy.
Remarkably, just one to two per cent of men in the HIFU trial experienced long-term urinary incontinence, compared to between ten and 20 per cent of men who have a surgical procedure to remove the entire prostate and the cancer inside it, or the other more traditional treatment of radiotherapy.
And just 15 per cent of the HIFU patients suffered erectile dysfunction, compared to between 30 and 60 per cent of men who had surgery.
Consultant urologist Hashim Ahmed, who led the study, explained: 'Years ago all women with breast cancer had a mastectomy, the surgical removal of the breast. Today it is more common to offer a lumpectomy, in which just the cancerous lump is removed, in addition to other treatments such a chemotherapy, radiotherapy or hormonal drugs.
'This is a similarly conservative approach to prostate cancer, which is why there are fewer side effects.
'In our study, 93 per cent of men were still free of prostate cancer after five years having had focal HIFU alone.'
Currently the National Institute for Health and Care Excellence (NICE), which provides guidelines for doctors, sanctions HIFU treatment on the NHS only if part of a clinical trial in specialist hospitals. This means that while it is widely available in America, the treatment is mainly offered privately in the UK, at a cost of £10,000.
Experts hope the new study's stunning results will pave the way for the treatment being more widely offered in Britain.
Prostate cancer is the most commonly diagnosed cancer in men, and the third most common cause of cancer-related death in Europe.
About 5,000 radical prostatectomies are carried out on the NHS each year and Mr Ahmed, of Nuada Urology London, believes around half could benefit from focal HIFU.
'Men with more than one large tumour in their gland, men with cancer that has spread outside the prostate and men with high-grade [aggressive] cancer are all ineligible,' he added.
The procedure, carried out under a general anaesthetic or spinal block, involves no incisions. Instead, an ultrasound probe is inserted into the patient's back passage.
The prostate is a walnut-sized gland that sits just beneath the bladder, surrounding the urethra. It is responsible for the production of seminal fluid - part of the male reproductive system.
Because of the position of the prostate, any invasive treatment to it can affect the surrounding nerves, which are also responsible for bladder control and erectile function.
The focused sound waves destroy tumour cells by heating them to almost 100C while causing minimal damage to surrounding healthy tissues and nerves.
The treatment is possible thanks to new, highly accurate computer-guided diagnostic techniques that can pinpoint the tumour.
The study followed 625 HIFU patients from 2004 to 2015. All of them had tumours that were confined to the prostate and had not spread to other areas of the body.
Mr Ahmed said: 'We do not yet have evidence for survival rates between five and ten years, but the procedure seems to offer the same cancer control as radical prostatectomy. We are looking at whether adding drug treatments before or after focal HIFU will increase its effectiveness.'
One in eight men will develop prostate cancer, and about 8,000 over-65s are diagnosed each year. Unlike cervical cancer smears for women, there is no regular screening programme because there is still controversy about whether diagnosing the cancer early is better.
Prostate cancer that has not spread is classified into three risk categories. Low-risk disease does not need aggressive treatment and instead men are offered 'active surveillance' which involves regular blood tests to monitor levels of prostate specific antigen (PSA). If these levels rise sharply, the cancer may have progressed to a stage where surgery is required.
In the new HIFU study, 87 per cent of patients had medium or high-risk prostate cancer.
One patient to have undergone the treatment is John Quinn, 60, a married father of two.
The businessman from Hamble, Hampshire, was diagnosed with prostate cancer in 2009, and initially opted for a radiotherapy treatment known as brachytherapy, in which tiny radioactive 'seeds' are inserted into the prostate, destroying the cancer.
Although effective, the risks are similar to those posed by surgery.
John said: 'My older brother also suffered prostate cancer and had surgery. That day, his sex life effectively ended. The thought of being left impotent and incontinent filled me with dread.
'By chance, a friend mentioned he had read about HIFU, so I booked a consultation with a private doctor.'
The operation was carried out privately in 2010. It was a success, and Mr Quinn is still cancer-free.
'And it hasn't affected the quality of my sex life,' he said.
- Daily Mail