Scientists have announced the development of a highly accurate and reliable technique for diagnosing prostate cancer. The Dundee University-based team say they have used an ultrasound process called shear wave elastography to detect prostate tumours. The method is non-invasive and cheaper than current detection techniques.
Prostate cancer has become the most common cancer in men in the UK. One in eight men will develop the condition at some point in their lives with more than 47,000 new cases being diagnosed every year. Men aged 50 or over, men with a family history of prostate cancer, and black men are at greatest risk of developing the condition. “Current diagnosis of prostate cancer is extremely inefficient, leading to unnecessary treatments for many patients,” said the Dundee University team’s leader, Professor Ghulam Nabi. “Our new method is far more accurate and also allows us to identify the difference between cancerous and benign tissue in the prostate without the need for invasive surgery.”
The prostate is a small gland in the male reproductive system and is normally about the shape and size of a walnut. Current methods for determining if a prostate has become cancerous include a physical examination of the prostate (known as a digital rectal examination or DRE), MRI scans, a biopsy or tests to determine levels of the chemical prostate-specific antigen (PSA) in the blood. Each carries problems. PSA results can be unreliable; a DRE is not good at identifying which cancers are benign and which need treatment; MRI scans cannot always give a definitive answer; while a biopsy carries a risk of infection and is expensive.
The new method aims to get around the problems by targeting the prostate with ultrasound. Cancerous tissue is stiffer than normal tissue, so shear waves are slowed as they pass through a tumour. “We have been able to show a stark difference in results between our technology and existing techniques such as MRI,” added Nabi. “The technique has picked up cancers which MRI did not reveal. We can now see with much greater accuracy what tissue is cancerous, where it is and what level of treatment it needs. This is a significant step forward.” The trial tests involved around 200 patients. “Now we need to use this on a wider scale to build more data, but there is the potential to change the way we manage prostate cancer,” Nabi said.
SWE technology is already used in diagnosing breast cancer and liver diseases. However, to make it applicable to prostate cancer, a special probe had to be developed by the team. “The technique now needs to be tested in a much larger number of men to confirm just how well it can detect the aggressive cancers, while also ruling out those who do not have prostate cancer,” said Simon Grieveson, head of research funding at Prostate Cancer UK, which funded the Dundee project (with support from the Movember Foundation). “With an average of one man dying every 45 minutes from prostate cancer in the UK, the need for a more reliable test that can identify dangerous forms of the disease earlier is greater than ever.”
In the past few years, a number of celebrities have revealed that they had been diagnosed with prostate cancer and had joined campaigns to raise awareness of the disease, including Michael Parkinson, Ian McKellen and most recently Stephen Fry, the comedian and former rector of Dundee University, who this year described how he had surgery to deal with a prostate tumour. “This breakthrough comes at a time when prostate cancer is being pushed to the forefront of our consciousness in the UK, not least because of the disturbing upward trend in its prevalence,” said Fry. “It is therefore doubly exciting to hear of the new techniques in diagnostic imaging.
Credit: Robin McKie for The Guardian, 22 April 2018.