Prostate cancer: why one of the most common cancers among men is so hard to diagnose (and how a new approach might change that)
Prostate cancer is one of the most common forms of cancer in men, with about 1.2 million new cases a year, according to the Spanish Cancer Association. Even so, the procedure used to diagnose the disease is not very accurate.
"Traditionally, we use a blood test to look for elevated levels of a prostate-specific antigen (PSA) and then we do a biopsy, which means we take tissue from the prostate to examine it under the microscope," Mark Emberton, a professor of interventional oncology at University College London (UCL), told the BBC.
"But PSA levels are not a reliable indicator of prostate cancer: about 75% of men who test positive do not have cancer, while (the test) fails to detect cancer in about 15% of men who do.
Today, the expert continues, "we diagnose cancers that are harmless, leading to unnecessary investigations and operations, and we overlook cancers that are harmful, leaving the disease to multiply and move through the body unchecked.
Like a mammography
Emberton is currently part of the UCL-led ReIMAGINE project, with researchers from Imperial College, Kings College London, and doctors from UCL hospital.
The team is exploring whether magnetic resonance imaging (MRI) can be used to make an effective diagnosis of prostate cancer in men, in the same way, that mammography is used to detect breast cancer in women.
"We hope that by using MRI we can change the way prostate cancer is diagnosed and treated," says Emberton.
"We know from international research that MRI can significantly and safely reduce the number of patients who need an invasive biopsy.
"These investigations recently led to changes in official health recommendations, and it is now suggested that MRI be done as the first test for men referred to the hospital by their general practitioner with suspected prostate cancer.
How is the trial being conducted?
Starting this month, 300 men between the ages of 50 and 75 will be randomly selected and offered the chance to join the trial.
Each patient will have a PSA blood test and a 10-minute MRI.
By combining the work of radiologists and urologists to analyze the results of both tests, they will be able to more accurately assess whether or not the patient has signs of prostate cancer.
Why is this important?
By capturing the harmful cells as early as possible, treatment can be started faster and that significantly improves outcomes for affected men and ultimately saves lives, Emberton tells the BBC.
It will also mean fewer biopsies are taken and that will reduce the cost to the health care system, he adds.
"Another important aspect of the study is that it will examine whether, in combination with advanced techniques such as genomics (...), magnetic resonance imaging can replace prostate biopsies.
"Prostate cancer patient groups are a tremendously important part of the study, and the prospect of greatly reducing biopsies is an important goal as these can have serious side effects on patients," says the expert.
These side effects include pain, bleeding, and infection.
"Our team hopes to recruit 1,000 men at medium to high risk for cancer to find out if MRI can be combined with other high-tech diagnostic tests to predict cancer progression," Emberton explains.
"The ultimate goal is to develop tests that are better than biopsies for determining the appropriate cancer treatment for each person, and to determine even if this person does not need treatment.
Emberton and her team hope that, as a result of the study, they will be in a position to rule out a biopsy and calculate risk based on MRI and blood tests alone.
"Detecting and treating prostate cancer using advanced imaging techniques is one of the most revolutionary discoveries I can remember in men's health, and it builds on the multidisciplinary experience of university researchers and physicians around the world," the expert said.
"Working together, we will continue to make significant discoveries to fight cancer".
Source BBC Mundo