New research is suggesting that a simple blood test can give doctors an idea of how aggressive a patient's prostate cancer is.

Researchers from Italy examined 1,017 prostate cancer patients who had radical prostatectomy surgery at Milan's San Raffaele hospital. The team had data on the patients' sex hormone levels and their Gleason scores, which come from a doctor's assessment of prostate cancer tumor tissue.

Gleason pattern 1 would indicate that the tissue cells are normal, whereas Gleason pattern 5, which is the highest score, would mean that the tissue sample has been taken over by a lot of tumor cells. A total of 118 patients had Gleason pattern 5 in the study.

After assessing hormone levels in relation to Gleason scores, the researchers found that low sex hormone levels, which is known as hypogonadism, and sex-hormone-binding globulin (SHBG) levels can predict which patients have Gleason pattern 5.

"We found that hypogonadism, and the levels of SHBG, were able to predict whether or not patients had Gleason factor 5, which is the worst Gleason score," lead study investigator Marco Moschini said. "This association will allow us to predict what the outcome will be before we decide to treat a patient with surgery. Potentially this can be helpful to identify patients with the most aggressive prostate cancer before surgery."

The researchers added that even though they found an association, more studies should be conducted to further examine the link between hypogonadism and a man's risk of being diagnosed with high-grade prostate cancer.

"Several reports in the literature mention that low serum testosterone level is associated with prostate cancer aggressiveness," said Alexandre de la Taille, a member of the European Association of Urology Scientific Congress Committee. "This study highlights the fact that SHBG is also linked to high Gleason score. These cancers, developed in this special hormonal environment, are probably due to different molecular pathways and represent a new field to explore."

The Centers for Disease Control and Prevention (CDC) reported that in 2012, 177,489 men were diagnosed with prostate cancer and 27,244 died.

The findings were presented at EAU 2016 meeting in Munich.