alephnull said...
Just IMHO, G6rs should be upgraded to the next step if their biopsy has any type 4 or 5 cells.
IE some 4 but no 5, then G7 3+4 ,
or ANY 5 then G8 3+5
As we all know, these are the more aggressive cancer cells, and given enough time may well become more extensive.
No, I don't have any studies, just a bit of common sense.
That is precisely what happens according to the TMN staging guide that pathologists use (currently in its 8th edition). In the U.S., one's biopsy Gleason score is that of the lesion with the
highest Gleason grade. As an example, say your latest biopsy shows (a) three lesions that consist of only Pattern (Grade) 3 and (b) one lesion made up of Patterns 3 and 4.
Each of your (a) lesions is graded G6 (3+3). Your (b) lesion will be graded either G7 (3+4) or G7 (4+3). The predominant pattern (making up 50% or more of this lesion) is listed first. Assume Pattern 4 is estimated to account for 55% of this lesion. This gives a Gleason score of G7 (4+3) to lesion (b) and gives you an overall biopsy score of G7 (4+3) as well.
You can have a G8 score with three different pattern combinations: G8 (4+4) is the most common, but if there is no Pattern 4, you could be 5+3 or 3+5, again depending on the predominant pattern.
There are more complicated rules for certain tertiary Patterns 4 or 5 (when pattern 4 or 5 accounts for less than 5% of the malignant cells in the lesion).
While there is some estimation in assigning the pattern percentages,
the assignment of Gleason scores isn't wishy-washy or a matter of opinion, but rather should follow the rules set out in the current TMN staging guide.This is crucial, because we all basically rely on the Gleason score to make treatment decisions! Depending on the severity of the upgrade, a man on active surveillance may be told that--base on his latest biopsy--that he is no longer a good candidate and should seek treatment. This holds for men whose latest biopsy confirms their G6 (3+3) score, but for whom the number and/or extent of the lesions has increased to the point where it can't be assumed that there are no higher-grade lesions elsewhere. (Although Gleason 6 itself cannot metastasize, it can sometimes grow through the prostate capsule--another reason to seek treatment).
Before the advent of genomic testing, it has been assumed that the risk of metastases always increased with the Gleason score. We now know this isn't strictly true. Men with any Gleason score can be
low, intermediate, or high risk for developing metastases within 5 years from testing. What does increase with the Gleason score is the
percentage of men in each risk group. If your cancer has grown out of the prostate capsule, this also skews up your chances of being in a higher risk group for mets.
For example, I was lucky that, despite having a RP-confirmed Gleason score of 9 (4+5), I tested low risk for mets (of course
low risk does not mean
no risk). To summarize, the
percentage of G9 men in the high-risk category is much higher than the percentage for, say, G7 men in this same category.
Djin