From the AACR Blog: What Is a Gleason Score for Prostate Cancer?

May 22, 2025

PHILADELPHIA – On May 18, former President Joseph R. Biden announced he had prostate cancer with a Gleason score of 9. Cancer Research Catalyst, the official blog of the American Association for Cancer Research (AACR), published a post today to explain what a Gleason score is.

Read the post: What Is a Gleason Score for Prostate Cancer?

The post details how a Gleason score is calculated and what each score means regarding the risk of growing and spreading. It also highlights how clinicians use the grading system to guide treatment for patients with prostate cancer. The post underscores that while the Gleason score is important, it is just one of many factors that determine risk and guide treatment for prostate cancer.

Journalists are encouraged to use this blog post as a resource to support accurate reporting. Please cite the American Association for Cancer Research and link to the post.