Context The recent increase in ability to diagnose prostatic
adenocarcinoma has created a dilemma for treatment decisions.
Objective To determine whether prostate cancer progression is
associated with a modified version of the Gleason grading system
together with selected morphologic and clinical variables.
Design Retrospective analysis of a cohort of patients with
peripheral zone prostate cancers who underwent surgery between August
1983 and July 1992.
Setting University hospital.
Patients Radical prostatectomy specimens from 379 men treated only
by surgical excision were prospectively studied for 8 morphologic
variables using previously standardized techniques. Variables were
percentage of each cancer occupied by Gleason grade 4/5 (% Gleason
grade 4/5, the Stanford modified Gleason scale), cancer volume,
vascular invasion, lymph node involvement, seminal vesicle invasion,
capsular penetration, positive surgical margin, prostate weight, and
preoperative prostate-specific antigen (PSA) level.
Main Outcome Measure Biochemical progression of prostate cancer as
indicated by serum PSA level of 0.07 ng/mL and increasing.
Results Cancer grade expressed as % Gleason grade 4/5 and cancer
volume were highly predictive of disease progression. In a Cox
proportional hazards model that included % Gleason grade 4/5, the
traditional Gleason score was not an independent predictor of treatment
failure. Positive lymph node findings and intraprostatic vascular
invasion were the only other variables that remained significant at the
Conclusion The % Gleason grade 4/5, cancer volume, positive lymph
node findings, and intraprostatic vascular invasion were independently
associated with prostate cancer progression, defined by an increasing
PSA level. Techniques to accurately measure cancer volume and %
Gleason grade 4/5 are needed to better predict which patient will
experience cancer progression. The commonly accepted predictors of
progression—capsular penetration and positive surgical margins—were
not independently predictive of failure after radical