The conventional diagnostic procedure for prostate cancer — the PSA test — has long been considered wildly inaccurate. As a result, doctors can’t distinguish between life-threatening cases of prostate cancer and less-lethal tumors by using PSA screening alone.

But a new high-tech procedure — MRI-guided biopsy — is promising to change all that. A man first undergoes a specialized MRI which can identify prostate cancer cells by measuring factors such as blood flow, water movement, and tissue density. A radiologist then rates suspicious areas on a five-point scale, with a score of five indicating the highest degree of suspicion.

During the actual biopsy, the MRI image is fused to ultrasound so a robotic system can precisely sample the most suspicious areas. The results can then help doctors determine which men would most benefit from surgery, radiation, and other treatments, and which can simply monitor their cancers without fear of the tumors spreading.

Currently, a man with a suspiciously high PSA — short for “prostate-specific antigen,” which can indicate the presence of cancer, but also other conditions — is typically directed by his doctor to undergo a prostate biopsy. During this unpleasant and painful procedure, doctors remove 12 or more randomly chosen tissue samples from the walnut-sized prostate gland and send them to a laboratory for analysis.

The results are often inconclusive, meaning that a man may have to undergo several more excruciating prostate biopsies. The results also can be shockingly misleading. In an astonishing 50 percent of cases, doctors either misdiagnose low-grade cancer as high grade or high-grade cancer as low grade.

Either way, the consequences can be devastating:

•    A man with low-grade cancer may undergo pointless surgery or radiation that leaves him incontinent, impotent, or both.
•    A man with high-grade cancer may not undergo any treatment and end up dead.

Every year in the United States, there are an estimated 233,000 new cases of prostate cancer and 29,480 deaths from the disease. Among men, prostate cancer is second only to lung cancer as the most lethal type of cancer.

“We have been heavily criticized as a field for using this random approach of detection,” says Dr. Samir Taneja, co-director of the Smilow Comprehensive Prostate Center at New York University.

He explains that the new MRI-guided biopsy procedure doesn’t involve taking a dozen or more random samples of the prostate, which is common with a conventional biopsy.

It also yields much more accurate results. It’s three times as likely to identify cancer, especially high-grade cancer. In only about 20 percent of cases does it mischaracterize high-grade cancer as low grade or low-grade cancer as high grade.

“We think we can provide more accurate data to patients to help them in deciding what treatment option would be appropriate for them,” Dr. Taneja tells Newsmax Health.

A year ago, MRI-guided biopsies accounted for less than 1 percent of the 1 million prostate biopsies performed each year. Dr. Taneja’s center at NYU was one of fewer than 20 centers nationwide to offer the procedure.

“Now it’s taking off like wildfire,” says Dr. Taneja. “I think that there are now centers that do good prostate imaging in almost every city.”

Medicare and many private insurers cover all or part of the cost of an MRI-guided biopsy. Since an MRI can cost $600 to $2,000, however, some insurers are reluctant to authorize one until there’s been a confirmed prostate-cancer diagnosis. In such cases, they may not cover the initial MRI but usually will cover the actual biopsy.

Given the advantages of MRI-guided biopsy, there’s little reason for a man not to request it instead of a conventional biopsy. For now, though, it’s still considered a somewhat investigational procedure.

Dr. Taneja advises patients to have it performed only by an experienced urologist at a center that has done a large number of such procedures.

New, large-scale studies are underway that could soon establish MRI-guided biopsy as the new standard.

Ultimately, researchers may show that an initial MRI combined with PSA testing is enough to determine if a man even needs a biopsy.

“If we do that, and we can prove a cost benefit to doing that, we may do away with a lot of the issues of over-detection that have haunted our field for the last 20 years,” says Dr. Taneja.

The full version of this article appeared in Health Radar newsletter. To read more, click here.