GS7 (3+4) Low yield of GS4 can be treated as GS6

Minuscule gleason pattern 4 component in GS7 (3+4) maybe treated same as GS6


Abstract


A modified Gleason grading system as proposed in the 2005 International Society of Urological Pathology (ISUP) consensus meeting is the current grading system for prostate cancer. With this modified ISUP Gleason grading system, many Gleason score (GS) 6 cancers by the old grading system are upgraded to GS7 cancers on biopsy diagnosis even with minimal quantity (<=5%) of Gleason pattern 4 (GP4) component (GS7miniGP4). However, grade concordance between the core needle biopsy of GS7miniGP4 and the corresponding radical prostatectomy (RP) specimens has not been studied. In this study, we analyzed the pathologic features of 256 consecutive needle biopsies and their corresponding RP specimens. The quantity of GP4 was calculated as the percentage of total cancer for GS7 cancer in the biopsy. Of 256 biopsies, 88 (34.4%), 107 (41.8%), and 61 (23.8%) had a GS of 6, 3+4=7, and 4+3=7, respectively. Of 107 biopsies with GS 3+4=7, 22 (20.6%) are GS7miniGP4. Ten of 22 cases of G7miniGP4 in the biopsies (45%) had pathologically insignificant tumor in the RP. The quantity of GP4 in the GS7 biopsy significantly correlated with GS, pathologic stage, and total tumor volume in the corresponding RP. The GS, pathologic stages, total tumor volume, and insignificant tumor rate in RP were not significantly different between the biopsy groups of GS 3+3=6 and GS7miniGP4, whereas those parameters were significantly different between biopsy groups of GS 3+3=6 and GS 3+4=7 with GP4 6% to 50% and between biopsy groups of GS7miniGP4 and GS7 with GP4 6% to 50%. Our data demonstrate that pathologic parameters in the RP are similar between the biopsy groups of GS7miniGP4 and GS6, and the grading of cases with biopsy GS7miniGP4 is often downgraded in RP specimens. The clinical significance of minimal quantity (<=5%) of GP4 in biopsies with GS7 prostate cancer needs to be further evaluated, particularly because of its potential impact on clinical decisions between active surveillance versus surgery.


http://www.ncbi.nlm.nih.gov/pubmed/24832163

This is very interesting to me. In my biopsy results, 80% of affected tissue was 3+3. Another 20% was 3+4, but it was described as "3 + focal 4 = 7". I don't really know what percentage that would work out to, because they didn't describe percentages of GP3 vs GP4 in that one sample, but it had to be less than 1/2 of the affected tissue, or it would have been 4+3. That means at least 90% was GP3, and the fact that the GP4 was focal indicates that I may have made that 95% threshold.

I asked my urologist about doing active surveillance with those numbers, given the low quantity of GP4 and his answer was no. Any GP4 meant treatment to him. This was before we had even discussed how I would have it treated; I had not committed to surgery (with him or anyone else) yet. That doesn't mean he wasn't steering me towards his bottom line though.

So, my biopsy might have met the GS7miniGP4 standard. If I'd seen this information 8 months ago, I might have pushed harder for active surveillance.

Instead I had surgery and the surgical pathology showed that 10% of the gland was involved, and approximately 5% of the tumor volume was GP4. So, I was not downgraded to 3+3 post-surgery, as the abstract mentions some GS7miniGP4 patients are, but the post-op pathology does put me in the GS7miniGP4 group.

This is one more piece of information that makes me wonder if I was over-treated. I made the decision to go forward with the treatment, and I've had good numbers since the surgery. I've even started to see some improvement in the ED area. So, given what I see on this board every day, I'm not complaining. Just wondering. I'm almost certainly not that 1 in 1000 lives that was saved by screening, but I may have been one of the 20 in 1000 patients who is treated unnecessarily.

I know I would not have been allowed to resume testosterone replacement therapy if I'd been on active surveillance, so maybe I would have opted for surgery anyway. But, perhaps my urologist was a bit quick to say that any GP4 meant I needed to get it treated rather than watching it carefully.

What's done is done, but it certainly is interesting.

Good to know and even better to know that my treatment would have an even better chance of working out long term.

I wasn't overtreated given my circumstances.