116grove said...
I saw “ “G 3+4=7 tert 5 T3b” in STW’s signature. What does “tert 5” mean?
tert. stands for "tertiary." It usually applies to RP grading. In G7 (3+4), pattern (or grade) 3 is the predominant pattern seen in a biopsy core (or prostate-wide in a post-RP report). The predominant pattern accounts for > 50% of the malignant tissue. The next-most common pattern is the secondary one, which is listed second (a 4 in this case). The majority of pathologists (but not all) won't assign a secondary pattern if it is < 5 % of the malignant tissue.
A tertiary pattern 4 or 5 is reported when the pattern is <5% and that pattern is higher than either primary or secondary pattern. It's a relatively recent addition to Gleason-score reporting.
The bottom line is that the G score should be taken more seriously, especially regarding treatment.I've seen studies in the literature that suggest a Gleason score with a tertiary pattern should be considered approx. equal in risk to the next-higher Gleason score (without a tertiary pattern).
So for G7 (3+4) tert. 5, we know the grade 3 was >50%, the 4 was < 50%, and the 5 was <5%. Pathologists are encouraged to report the percentage of the more serious primary or secondary pattern.
A pathologist won't bother listing a "tertiary 3," because it's of no importance when your Gleason score is (4+4), (4+5), or (5+4). Nor is a tert. 4 of importance with a G10 (5+5).
I believe there are six G scores that can have a tertiary grade:
G7 (3+3) with tert. 4 or tert. 5 (I would think its possible to have both)
G7 (3+4) or (4+3) with tert. 5
G8 (4+4) with tert. 5
G8 (5+3) or (3+5) with tert. 4
At least this is my understanding.
Grading of prostatic adenocarcinoma: current state and prognostic implications (2016, Full Text)
This is a paper, coauthored by J. Epstein, that proposed tertiary reporting practices.
"Tertiary grades are provided only in radical prostatectomy specimens, when in a nodule there is a third component of a Gleason pattern higher than the primary and secondary patterns, and where the tertiary component is <5 % of the whole tumor. When the 3rd most common component is the highest grade and occupies >5 % of the tumor, it is typically recorded as the secondary pattern. So 50 % pattern 4, 30 % pattern 3, and 20 % pattern 5, would be reported as 4 + 5 = 9."
I've deleted a statement I made about this based on Mumbo's post below. I think the authors do mean that tertiary reporting is done only in RP reports and not for biopsies. [b/]
Djin