Can MRI scans improve the accuracy of prostate cancer screening?

There is both good news and bad news when it comes to prostate cancer testing. First, the bad news. Blood tests that measure a compound called prostate-specific antigen (PSA) are too inaccurate. As a result, some men end up undergoing cancer treatments they didn’t actually need, causing incontinence and erectile dysfunction.

On the other hand, combining a PSA test with an MRI scan of the prostate can make screening more accurate, especially if double testing is recommended only for people at high risk of tumors. An expert group called the Lancet Committee on Prostate Cancer made this recommendation in a new report.

We certainly need to rethink prostate screening, but will these new proposals succeed in reducing harm?

Prostate testing has long been controversial. PSA is released at high levels by cancerous prostate cells, but is also produced at low levels by healthy prostate cells.

Blood tests were introduced as a way to track the success of cancer treatment. It began being used as a screening test in the 1990s, in part as a result of a campaign by men’s health groups for something comparable to breast cancer testing.

The problem is that PSA alone is not reliable as a screening tool. Levels may rise temporarily, such as after sex, during a urinary tract infection, or while riding a bicycle. Even if the increase continues, most prostate cancers grow so slowly that if left untreated, they will never be noticed or cause any problems.

These problems wouldn’t be so important if it weren’t for the fact that the treatments used to remove the cancer (usually surgery or injecting radioactive material into the tumor) can cause permanent incontinence and erectile dysfunction. It would have been. Biopsies to determine whether cancer is present can also cause these problems.

randomized trial It has been shown that for every 1,000 men who undergo regular PSA testing, one fewer man will die from prostate cancer over a 10-year period, but three will remain incontinent and 25 will remain impotent.

These disturbing figures are forcing health services in most high-income countries, including the UK and Australia, into uneasy compromises. Unlike breast and colorectal cancer tests, no invitations for prostate tests will be sent out, but those who wish to undergo the test can take it if the risks are explained to them.

As a result, higher-income men are more likely to take the PSA test, and lower-income and black men are less likely to be tested, the new report says. This is unfortunate because men of African descent are about twice as likely to develop prostate cancer as men of European descent.

The report’s authors say health systems need to use more sophisticated forms of screening, including both PSA tests and MRI scans. This scan allows your doctor to assess the size of your prostate and identify suspicious areas that may be cancerous.

Something close to this dual method is already in place in some countries, including the UK, where the next step for people found to have high PSA levels is an MRI scan. This means that people who are reassured by their scan results can avoid a more invasive biopsy. “This greatly reduces the problem of overdiagnosis,” he says. nicholas james, a researcher at the Institute of Cancer Research in London and one of the authors of the report.

But James says it may be even better to combine the PSA test with an MRI scan before the results are fed back to avoid men being mistakenly told they may have cancer.

The committee says health care organizations should use this combined approach to launch formal screening campaigns targeting three groups known to be at high risk. Black men, people with a family history of prostate cancer, and men who have a mutation in one of their prostate cancers. BRCA Genes also associated with breast cancer.

This would avoid the current situation where men at low risk are probably getting too many PSA tests, while men at high risk are getting too few or no PSA tests.

The proposal is certainly suggestive, but it remains to be seen whether it will discourage people from getting prostate exams. recently” cure cancer phobia.

The arrival of the PSA test may be like opening a Pandora’s box, James says, but the proposed new approach will likely alleviate at least some of the harm.