taken from Small Gland, Big Problem 4th Edition
by Professor Roger Kirby, Health Press 2011
If cancer is suspected, your urologist will first need to check whether you do in fact have cancer by performing a biopsy, which involves taking some tiny samples from the prostate while you have either a local or general anaesthetic. If you have, he will then need to determine how aggressive it is and how far it has progressed. You may hear a reference to the grade and stage of your cancer. These are important in selecting the best treatment option for you.
The grade is a measure of how aggressive the cancer is. The cancer cells in the prostate start out looking very similar to normal prostate cells, but start to change their appearance and de-differentiate (i.e. become more aggressive) as the cancer progresses (see page 31). Grading is a means of assessing this process in a standardized way,
and is performed in a laboratory by specialist pathologists.
The standard grading system is the Gleason score. From incidental post-mortem findings, we can speculate that low-grade ‘latent’ prostate cancer is probably quite common among men aged over 40; these small tumours often grow very slowly, and so many men will never develop symptoms during their natural lifespan. However, a cancer that progresses more quickly (that is, a more aggressive one) will show a less ‘differentiated’ pattern, and will be graded higher. The cancerous areas in the prostate may vary and have different grades, so the grades of the two most prominent areas are added together to give a Gleason score (for example, 3 + 4); the maximum is 10 (5 + 5). This figure then gives your doctor an idea of how quickly your cancer is likely to progress and therefore helps him advise you about treatment.
|Gleason score and the risk of prostate cancer progressing|
The cancer can also be classified according to how far it has spread, that is its ‘stage’. The tumour–nodes–metastases (TNM) system is commonly used, and involves the doctor assessing how far your cancer (tumour) has spread in and around the prostate, whether it has spread to the nearby lymph nodes (nodes) and then whether it has spread (metastasized) to the distant lymph nodes and bones. Knowing the stage of your cancer helps you, your family and your urologist to decide on the most appropriate course of action.