Volume of Cancer in one Core

Pratoman-

That was a very expected response from Dr. Epstein. While he holds a lot of weight in my book, you should be aware that the prognostic implications of volume of disease is a very controversial subject.

Johns Hopkins has possibly the strictest AS criteria in the country. They've been threatening to relax their criteria, but haven't yet officially, as far as I know. They follow the "Epstein criteria," although based on his email to you, it sounds like he's already moved away from maximum % in any core. The Epstein criteria are (in addition to the standard criteria for low risk PC):
• No more than 2 positive cores
• No more than 50% involvement in any core
• PSA density ≤.15

NCCN (Johns Hopkins is an NCCN hospital but marches to its own drummer on this) uses the Epstein criteria to define a "Very Low Risk" sub-category, but endorses AS for all low risk men. UCSF uses something they call the CAPRA score system for risk assessment. It uses "% involvement over 34% in a core" as one of several factors affecting risk, but they do not use number of positive cores - it was not a significant factor in their data set. There are various nomograms out there, and the importance of cancer volume varies with the data set they used. Klotz at UToronto and Scholz are on the more liberal end, accepting some men with GS3+4 into their AS programs (and don't include cancer volume in their official criteria, although they may consider it individually).

There are several problems with using biopsied cancer volume, especially with the popularity of advanced imaging with mpMRIs and CDUS.
• it doesn't take account of number of cores taken. An arbitrary call of "no more than 2 cores" is probably based on stats from 12 core TRUS biopsies. But what if there were 6 cores, or 30 cores?
• on repeat biopsies (like you've had) they may focus on areas previously known to harbor cancer, increasing apparent cancer volume.
• there is no standard core length. They typically range from 1-2 cms, but there are broken pieces, so % of a core means a lot of different things. One study used an arbitrary standard of 4 mm in length in a core as significant, but this isn't well established.
• it doesn't account for mpMRI or CDUS-targeted biopsies finding more of the cancer, and in more places in the gland.
• it doesn't account for the fact that the random biopsy is more likely to find the cancer in a smaller prostate.

But the advanced imaging is really the opportunity that gets around the problem of cancer volume. With mpMRI or CDUS-targeted biopsies (read by a proficient radiologist) it really doesn't matter what the prostate volume is. The important thing is, if it grows, you will know it (and if it increases in grade, you will know it) in time to treat it effectively.

- Allen

Compiler, I am somewhat flattered to be, by implication, grouped in the same category as those you mentioned. I will refer you to any of my posts on quantum physics. I actually believe some of my thoughts are equationable. But my math is weak. The dialectic method was, Im sure used by those you mentioned in their thesis/arguments. You used the term opposite, re their thesis's, which plays exactly into Quantum physics, tho physics use positive and negative. Im sure the the two philosophers mentioned labeled their thesis as positive and the others as negative. So to say your logic course was anti logic is to me not logical, i.e. Im sure they both used solid logic to prove their thesis, however coming to opposite conclusions. No one won the argument, but guarens a new thesis was created and ad infinitum or ad neaseum the process repeats. This is exactly the scientific method... which brings new knowledge. The scientific method is the dialectic method for discovery. It is used other places for the more esoteric,{ your word} I doubt this post satisfies your request for simple, but I won't quote Popeye. Hint... think like a sweet potato. BTW I consider posts like these GFMPH, and appreciate.

Pray for clean surf here folks Ive got way to much time on my hands.
Yooper man. Shredded wheat biscuits, the big ones like back in the day, with fresh blueberries, Costco fresh. Add at least 3 big cups of of black coffee for a themogenic pop. Its the exercise,ATC, prolific reading, with a dash of good memory and my reply to pratoman below

Pratoman, I honestly do not know where this crap comes from, but holy for sure is the operative word.

I did miss it, but I'm glad that you feel comfortable with your decision - although I don't understand why you were asking about cancer volume. Just an FYI post, I guess. Frankly, Dr. Tewari and his torsionless nerve-sparing is the only surgeon I would have considered for myself.

Averaging from most studies I've looked at, about a third are upgraded on post-RP pathology, and about 10% are downgraded, the rest remain the same. I don't think it's a contradiction or a disservice. It just means that clinical grades and staging has a different purpose and usefulness vs pathological grading and staging.

The main purpose of clinical grading and staging is for risk stratification purposes. Researchers use large sets of clinical data and correlate them with oncological outcomes to find the probabilities across the population. So, it is true, for example, that a clinical diagnosis of GS6 correlates well with low risk of recurrence, if all other factors are equally low risk. This correlation is true irrespective of final pathology results. These risk strata are then correlated with treatment outcomes to determine the expected success of each treatment across the population. I stress that all of this is population-based data, and none of it predicts for the individual.

- Allen

Hi All,

Sorry for the list foul/hijack.

ScientificLifestyle