You have received a prostate cancer diagnosis and a Gleason score. But how certain is that assessment, really? International studies show that up to 20 per cent of prostate cancer biopsies are assessed differently depending on which pathologist reviews them. That is not a marginal problem, but a structural challenge that can affect which treatment option you are offered.
How is prostate cancer assessed?
The aggressiveness of prostate cancer is assessed by a pathologist who reviews tissue samples under a microscope. The pathologist looks at how the structure of the cancer cells deviates from normal tissue and sets a Gleason score, a number that summarises how aggressive the cancer is judged to be. It is a visual assessment, and just like all visual assessments made by a human being it is subjective by nature. The whole route up to the test result (PSA, MRI and biopsy) is described under making a diagnosis.
What the research shows about the margins of error
In a study published in the journal Medical Image Analysis, based on data from 25,591 patients in six cohorts in three countries, the AI model PCAI was found to consistently outperform experienced specialists in uropathology on all external test cohorts. This is in line with the wider literature: international studies show that assessments can differ in up to 20 per cent of cases when the same biopsy is reviewed by different pathologists. The study is reported in full under PCAI's clinical results.
What does that mean in practice?
A man who is incorrectly judged to have aggressive cancer may undergo a radical prostatectomy with a risk of lifelong side effects, for a cancer that could otherwise have been followed with active surveillance. Conversely, a man whose cancer is underestimated in aggressiveness may miss treatment at the right time. This is not about carelessness, but a structural challenge in how the assessment method works.
What can you do?
The clearest option is a second opinion, an independent assessment of your tissue sample. It can be done by another uropathologist, or through AI-based analysis. Spearpoint Analytics' PCAI analysis assesses the aggressiveness of your prostate cancer based on the same tissue images, with an AI system trained on real long-term outcomes and validated in a study of 25,591 patients, not on a single point of assessment.
What is PCAI?
PCAI (Prostate Cancer Aggressiveness Index) is trained on patients' actual disease outcomes, not on the subjective assessment a pathologist makes at a given moment, and is validated in a study with follow-up of up to 23 years. In clinical studies, PCAI has consistently outperformed experienced specialists on all external test cohorts. The service is offered by Spearpoint Analytics as a second opinion directly to the patient. The clinic carries no regulatory responsibility, and you can order the analysis without your urologist needing to be involved. Read more about how PCAI works.
You may also find answers here:
- What is the Gleason score – and why can it be misleading? Article 5 – Gleason score explained
- PCAI vs. Gleason score – a direct comparison PCAI vs. Gleason
- Should you have prostate surgery? How to tell whether your diagnosis is certain Article 3 – Should you have prostate surgery?
Do you want to know how certain your assessment is?
An independent analysis of the same tissue sample can confirm or add nuance to the basis you already have.