Specific scores and patterns based on prostate cancer biopsy are linked to raised risk of PSA-failure, indicating that the reading might help predict prostate cancer recurrence risk, says an article in the Journal of the American Medical Association (JAMA), October 3rd issue.
The Gleason scoring system is used to facilitate diagnosis and treatment of prostate cancers. It grades malignant tumors (adenocarcinomas) of the prostate based on the patterns of prostatic glands. Several studies confirm that the Gleason score is useful in predicting how long to recurrence, and death, following therapy, explain the authors.
A scoring system of 1 to 5 (higher grade being less differentiated) is used by the Gleason score – with the predominant pattern being compared to the second most prevalent pattern in the prostate specimen. The two grades are added up and a final score of between 2 and 10 is reached. Although the Gleason scoring system does not include a 3rd pattern, the presence of over two Gleason patterns in an individual tumor is widely recognized to occur, and several pathologists use a third (tertiary) pattern.
Abhijit A. Patel, M.D., Ph.D., Brigham and Women’s Hospital and the Dana Farber Cancer Institute, Boston, and colleagues carried out a study comparing the prognostic impact of Gleason score 7 with tertiary grade 5 versus other Gleason scores with respect to time to PSA (prostate-specific antigen) failure (a rise in the blood level of PSA after treatment for prostate cancer with radiation or surgery).
During the period 1989-2005, 2,370 males with varying tumor grades and prostate cancer that had not reached to nearby lymph nodes or anywhere else in the body, received either surgery or radiation therapy with or without hormonal therapy. Gleason scores were assigned to the prostate needle biopsy specimens.
The scientists found that men with a Gleason score 7 and tertiary grade 5 disease took significantly less time to reach PSA failure compared to patients with 7 without tertiary grade 5 (midpoint time 5.0 versus 6.7 years respectively). Those with a score of 6 or less took 15.4 years to reach PSA failure. However, an appreciative difference was not observed when these patients were compared with men with Gleason score 8 to 10 disease (midpoint time 5.1 years).
The authors wrote “If these findings are validated by additional studies in other populations, they may affect the management of care for men with Gleason score 7 prostate cancer for which the currently practiced management standards include dose-escalated radiation therapy including prostate brachytherapy with or without supplemental radiation therapy, radiation therapy and short course androgen suppression therapy (AST) or radical prostatectomy. Specifically, given the time to recurrence, management options for men with Gleason score 7 who also have tertiary grade 5 disease could include treatments that are the current standards of care for men with Gleason 8 to 10 prostate cancer. These standards of care based on the results of randomized trials include radiation therapy and short- or extended-course AST or radical prostatectomy with the expectation that further therapy may be needed postoperatively depending on the final pathology findings of the radical prostatectomy and postoperative PSA level.”
JAMA. 2007;298(13):1517-1524
jama.ama-assn.org
Written by: Christian Nordqvist