Professor Mark Frydenberg AM discusses the Gleason score for prostate cancer grading and what a Gleason Score of 6, 7 and 8 signifies in terms of prostate cancer and its treatment.
Once a patient has been thought to have a level of suspicion of prostate cancer and has undergone a prostatic biopsy, the pathologist will have a look down the microscope at the tissues that he’s examining and will describe a Gleason score or Gleason grade if a cancer is detected. What this signifies is the level of aggression of the underlying malignancy, which often plays a very big role in the decision-making regarding the treatments.
With a Gleason score, the three common scores are a six, a seven or an eight. If you have a Gleason score of six, it’s considered an extremely low aggression cancer and in many of these circumstances no treatment will be recommended, but close surveillance will be recommended instead. A Gleason 7 tumour is considered intermediate risk and a Gleason 8 or above is considered a high-risk prostate cancer which is aggressive.
With the Gleason 7 tumours what they try and do is give us some idea about whether that seven is closer to a six, or whether it’s closer to an eight, and that is why we see the description, a Gleason three plus four equals seven which is the one that’s closer to a six, or four plus three equals seven, which is closer to an eight.
Again, a three plus four equals seven will still often require treatment, but in some cases may be suitable for surveillance, whilst it would be very unlikely for a Gleason four plus three or seven or above, to be offered surveillance and in those circumstances active treatment is likely due to the risk of the cancer spreading and potentially causing harm to you in the future.