Researchers say that men who show signs of inflammation in their initial prostate biopsies may have a reduced risk of being diagnosed with prostate cancer from future biopsies. This is according to a study published in the journal Cancer.
Investigators from the North Shore-Long Island Jewish Health System in New Hyde Park, NY, led by Dr. Daniel Moreira, say their findings suggest that since inflammation has a "predictive value," it should be regularly reported from prostate biopsies.
The link between inflammation and prostate cancer has been controversial, according to the researchers.
Previous studies have also suggested that inflammation of the prostate is associated with a lower risk of cancer, but other research has suggested that therapies to combat prostate inflammation reduces cancer risk.
To further examine the issue, the research team looked at data of 6,238 men aged between 50 and 75 years.
All men had previously undergone prostate biopsies that were negative, suggesting no sign of prostate cancer. Additional biopsies were conducted 2 and 4 years later.
On prostate-specific antigen (PSA) tests (a blood test determining the risk of prostate cancer), all men showed PSA levels between 2.5 to 10 ng/mL.
Inflammation linked to reduced cancer risk
From the analysis, it was found that acute inflammation was common from biopsies at the beginning of the study in men of younger ages who had lower PSA levels and smaller prostates. Men who were older with larger prostates were more likely to have chronic inflammation.
From the biopsies taken 2 years later, prostate cancer was detected in 900 men (14%).
The researchers found that men who had acute inflammation at baseline had a 25% lower risk of developing prostate cancer, while men with chronic inflammation had a 35% lower risk.
The biopsies taken 4 years later revealed that only acute inflammation was linked to a lower risk of prostate cancer.
The researchers hypothesize that inflammation may be linked to a lower risk of prostate cancer because inflammation occurs as part of an immune response when the body observes "malignant cells as foreign agents." The body may eliminate the cells before they turn into a tumor.
They say if this is the case, it is possible that monitoring and balancing inflammation and the body's immune response could assist the prevention and treatment of prostate cancer.
Commenting on the findings, Dr. Moreira says:
"Given its predictive value, inflammation - and its type and severity - should be routinely reported in prostate biopsies.
Also, it is possible that patients with inflammation at baseline biopsy may be followed differently compared with patients without inflammation at baseline biopsy, given their risk of subsequent cancer detection is lower."