ATLANTA, Ga. (CBS Atlanta) – A new study has found that prostate cancer tests underestimate the aggressiveness of the disease.
Researchers from the Cancer Research UK Cambridge Institute found that more dangerous tumors were discovered in more than half of a group of men whose cancers were initially classified as slow-growing and confined.
“Our results show that the severity of up to half of men’s prostate cancers may be underestimated when relying on tests before they have surgery,” Urological surgeon Greg Shaw, from the Cancer Research UK Cambridge Institute, told The Guardian.
This new discovery calls into question the ability of doctors to properly grade and stage prostate cancers on the basis of biopsy samples taken from men. In addition, the “active surveillance” strategy of avoiding unnecessary radical treatment for patients with slow-growing prostate cancer could be doubted.
Researchers compared the grading and staging of more than 800 men’s cancers before and after they had surgery to remove their prostate and found that of 415 patients whose cancer was classified as slow-growing and confined to the prostate, roughly 209 of them were found to have a more aggressive disease when assessed after surgery, The Guardian reported.
Also, nearly 131 of the men had cancers that had spread to areas beyond the prostate gland.
Professor Malcolm Mason, Cancer Research UK’s prostate cancer specialist, told The Guardian: “At the moment the bBiopsy, MRI and PSA tests that we use to assess the severity of prostate cancers are the best methods we have but, as this study shows, they don’t always get it right.”Despite the limitations that this study shows, all evidence so far points to active surveillance being safe provided men are carefully selected. But we need better methods of assigning a grade and stage so that no man has to unnecessarily undergo treatment, while at the same time making sure we detect and treat the cancers that really need it.”
According to the Centers for Disease Control and Prevention, 196,038 men in the United States were diagnosed with prostate cancer in 2010. Of that number 28,560 men died from prostate cancer.
The findings were published in the British Journal of Cancer.