Sunday, March 9, 2014
Men with High Gleason Score Prostate Cancer should be given honest appraisals and expectations of outcomes from treatment
Men with a Gleason score 8-10 cancers have a significant chance of not being cured by radical prostatectomy. Only in very exceptional circumstances would a man with a Gleason score 8-10 cancer be offered surgery if extent of disease scans (typically scans such as a bone scan and CT scan of the abdomen and pelvis) show evidence of spread to other organs.
The vast majority of men with Gleason score 8-10 prostate cancer are offered surgery because there is no objective sign of cancer spread on scans and provided other factors such as age and concurrent medical problems are not likely to be an issue. The big BUT is that if such scans fail to show signs of spread, it does not mean that spread has not occurred. We know for a significant number (at least 30-50%) will have already had microscopic spread that is simply beyond the resolution of the scans to detect. In other words, let’s say that some cancer cells from the prostate gland have managed to enter into blood vessels or lymphatic vessels and travel all the way to either the bones or lymph glands respectively. Remember that tiny deposits less than a millimetre is size would have no chance of being seen by a scan. Before operating on such men, we need to be honest with them about this possibility. They need to recognise that even if we are to successfully remove the prostate and have the prostate specimen margins free of cancer, it does not mean that they have necessarily been cured. It is simply one of a number of hurdles that have been jumped over.
Having a Gleason score 8-10 prostate cancer is bad enought but if we look at men who have Gleason score 10 cancer in particular, we would regard these men as having a very high (not just high) risk of existing microscopic spread. When these men undergo radical prostatectomy, a typical expectation is that less than 40% will be alive in 10 years without having signs of detectable spread of the cancer. Even fewer will be alive with signs of cancer having returned as evidenced by their PSA blood test levels. In other words, most men with Gleason score 10 cancer will not be able to be cured. This of course does not mean that these men should not be offered treatment with curative intent but it is an indication that appropriate counselling be offered and that men not be given false expectations about their prognosis. It would be brave to suggest to such men that after surgery for a Gleason score 10 cancer, that they had ‘beaten it’ just because the surgical specimen showed that the excision margins did not have cancer at the edges (also known as positive surgical margins). Another consideration is that these men who have arguable the worst prognosis, should be offered the opportunity to participate in clinical trials give them access to additional promising treatments that could offer them the best hope of overcoming these cancers. In my opinion, this is less likely to be offered in the setting of treatment by commercially driven surgeons.
There is more to treatment decision making processes than what the Gleason score is found to be on prostate biopsies. This blog piece attempts to show just one aspect of how we consider how we embark upon offering the best for our patients.
The intention was not to make this blog piece sound like an argument against offering men with the most aggressive prostate cancers any treatment. I regularly offer men with clinically localised 'high risk' prostate cancer treatment with curative intent. In spite of our recognition that many will experience signs of failure to cure the disease, treatment offers these men their best chance. Recent randomised control trial data shows that there is increasing evidence that treatment for this particular group of men makes a clinically relevant impact upon their survival.
On a final note, I draw attention to a tweet from Dr David Samadi who is a 'celebrity' urologist who claims cure rates of 97% from prostate cancer surgery - he indicates that he has a patient who had just recently undergone surgery who had now ‘beaten the disease’ and is celebrating. You make up your own mind whether the patient has been given realist expectations on what the future holds for his cancer. When the PSA starts rising, will Dr Samadi look after him now that the surgery is done, or simply refer him to another specialist (medical or radiation oncologist) to manage something that is no longer for him to look after? I do not know the answers to these questions but leave it in your mind to decide.