The information which follows is the opinion of the named author(s).
It does not necessarily constitute the opinion of The Prostate Cancer InfoLink or of
CoMed Communications, Inc.
Partin Table Predictions: What Do They Really Mean?
(A Pathologist's Analysis)
Jonathan R. Oppenheimer, MD, FCAP
Medical Director and Chief Pathologist, Oppenheimer Urologic Reference Laboratory (OUR Lab),
1854 Air Lane Drive; Suite 17A; Nashville TN 37210
Originally Received September 30, 1997.
[Although the Partin tables were updated in June, 2001, Dr. Oppenheimer's explanation can still explain how they work.]
The most recent [1997] edition of the so-called
Partin tables [1] represents a
remarkable joint effort of three major academic centers of prostate cancer
excellence. Data from 4133 men who had undergone radical prostatectomy (RP)
were collected from Johns Hopkins Hospital, the University of Michigan, and
the Baylor College of Medicine. These data were analyzed to determine the
value of combining readily obtainable preoperative information (PSA,
clinical stage, and
Gleason score) in predicting the extent of
the actual
tumor as determined by post-surgical pathological exam. The large amount
of data collected and tabulated in several charts allows patients and their
physicians to more accurately estimate the probability that surgical
intervention will result in complete removal of the tumor.
The application of these tables allows the patient and physician to arrive
at a more informed treatment decision, and encourages more frank discussion
regarding the benefits and risks of possible treatments. In order to
appreciate the relevance of the Partin tables, however, it is important to
understand what they actually predict rather than what they are
widely assumed to predict.
A major misconception in the minds of many is that the Partin tables
predict whether or not RP will be curative. Leaving aside the semantic
argument of whether or not "cure" is an acceptable term for a disease that
can recur many years after having been apparently successfully treated,
the Partin tables actually predict the results obtained on pathologic
examination of the
prostate and lymph nodes after surgery. While there is a logical and
scientifically proven correlation between the results of pathologic
evaluation and the patient's prognosis, these two "end-points" are quite
different. The divergence between the pathology and prognosis can be
attributed to several factors.
Some tumors which are "organ confined" on pathologic examination are not organ
confined in reality. In spite of the main mass of the tumor having been
removed, metastatic or micrometastatic deposits of tumor may have already become situated in
other parts of the body. Alternatively, since the pathologic examination
of the prostate entails the review of multiple planes of tissue taken from
a roughly spherical organ, the point of capsular penetration by the tumor
may be missed on microscopic examination.
Some tumors which demonstrate "capsular penetration" on pathologic examination are
taken from patients who do not show signs of biochemical (detectable PSA)
or clinical (symptomatic) recurrence many years after surgery. In a study
of 721 men at Johns Hopkins, 58% of men with clear-cut capsular penetration
had no evidence of biochemical recurrence ten years after surgery
[2].
Post-surgical manipulation of the RP specimen may induce tissue changes
(artifacts) that are mistaken by the pathologist as evidence of disease
extension. Perhaps inflammation or loss of local blood supply induced by
the surgery may somehow induce the regression of a small amount of tumor
left inside the patient. In view of the above, it is understandable why
some surgeons may not wish to deny their patients an attempt at possible
"curative" therapy even when faced with a substantial probability of
predicted non-organ-confined disease.
Patients may benefit from the removal of the great majority of their tumor
(so-called tumor debulking) and achieve longer life and decreased symptoms
even though not all of the cancer was removed. It has been shown that in
patients with no high-grade disease on biopsy, radical prostatectomy can be
beneficial even in the presence of locally invasive disease or seminal
vesicle invasion [3]. The value of tumor debulking is controversial and must
be weighed against the benefits of treatment alternatives with less
detrimental effects on the patient's quality of life.
It must be kept in mind that the Partin tables assume that it is the
postoperative pathologic stage which is of foremost importance in
assessing prognosis. Other investigators [4] have found preoperative PSA,
Gleason grade, and DNA ploidy to be more accurately predictive of eventual
outcome than pathologic stage.
Although the Partin tables can help to better evaluate therapeutic options,
it must always be remembered that these tables use statistical data to
predict probable outcome in an individual. Utilizing these tables may lead
to the acquisition of more "knowledge" that may leave one with the feeling
of even more uncertainty. We should also take into account other
preoperative prognostic data derived from the individual patient: the
number and laterality of biopsy cores involved with cancer, the percentage
of high grade cancer in biopsies [5], pathologic staging
[6], DNA ploidy
analysis, microvessel density [7], tumor proliferative markers, endorectal
coil [8] and spectroscopic MRI imaging [9],
radionuclide (ProstaScint)
studies [10], etc. The efficacy and cost-effectiveness of the
above-mentioned tests are -- unfortunately -- not known at present.
Nevertheless,
the Partin tables remain an extremely useful tool for empowering the
thoughtful patient and physician dealing with prostate cancer.
It is worth noting that others have also commented on the accuracy of the
Partin tables in predicting outcomes to prostate cancer
[11] and their relevance to patients of African-American
race [12]. Partin and his colleagues have responded to
these comments [13].
References
1. Partin AW, Kattan MW, Subong ENP, et al. Combination of
prostate-specific antigen, clinical stage, and Gleason score to predict
pathological stage of localized prostate cancer: a multi-institutional
update. JAMA 1997; 277: 1445-1451.
2. Epstein JI, Partin AW, Sauvageot J, Walsh PC. Prediction of progression
following radical prostatectomy. Am J Surg Path. 1996; 20: 286-292.
3. Naitoh J. PSA recurrence pattern following radical
prostatectomy for
stage pT3c disease. J Urol. 1997; 157: 803A.
4. Lerner SE, Blute ML, Bergstrahl EJ, Bostwick DG, et al. Analysis of risk
factors for progression in patients with pathologically confined prostate
cancers after radical retropubic prostatectomy. J Urol. 1996;
156: 137-143.
5. Stamey TA, McNeal JE, Yemoto CM, et al. Gleason sums of 7 lose
prognostic information in comparison to estimates of percent grade 4 and 5
cancer. J Urol. 1997; 157: 794A.
6. Narayan P, Gajendran V, Taylor SP, et al. The role of transrectal
ultrasound-guided biopsy-based staging, pre-operative serum PSA, and biopsy
Gleason score in prediction of final pathologic diagnosis in prostate
cancer. Urology 1995; 46: 205-212.
7. Bostwick DG, Wheeler TM, Blute M, et al. Optimized microvessel density
analysis improves prediction of cancer stage from prostate needle biopsies.
Urology 1996; 48: 47-57.
8. D'Amico AV, Whittington R, Malkowicz SB, et al. A multivariate analysis
of clinical and pathological factors that predict for PSA failure after
radical prostatectomy. J Urol. 1995; 154: 131-138.
9. Kurhanewicz J, Vigneron DB, Hricak H, et al. Three dimensional H-1
spectroscopic imaging of the in situ human prostrate with high spatial
resolution. Radiology 1996; 198: 795-805.
10. Burgers JK, Hinkle GH, and Haseman MK. Monoclonal antibody imaging of
recurrent and metastatic prostate cancer. Semin Urol. 1995;
13: 103-112.
11. Naitoh J, Dorey F, deKernion JB. Predicting pathological stage of
localized prostate cancer [Letter to the Editor]. JAMA 1997; 278: 980-981.
12. Petros JA. Predicting pathological stage of
localized prostate cancer [Letter to the Editor]. JAMA 1997; 278: 981.
13. Partin AW, Subong ENP, Walsh PC, et al. Predicting pathological stage of
localized prostate cancer [Letter to the Editor]. JAMA 1997; 278: 981-982.
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