Objectives: To determine the clinical significance of Gleason score 3+4 versus 4+3 on radical prostatectomy.
Methods: Of 2390 men who underwent radical prostatectomy by a single surgeon, 570 had Gleason score 7 tumors without lymph node metastasis, seminal vesicle invasion, or tertiary Gleason pattern 5. Patients were evaluated for biochemical recurrence (prostate-specific antigen progression) and distant metastases.
Results: Eighty percent of patients had Gleason score 3+4, 20% had 4+3. The rate of established extraprostatic extension at radical prostatectomy for Gleason score 3+4 and 4+3 tumors was 38.2% and 52.7%, respectively (P = 0.008). With a mean follow-up of 4.6 years for men without progression, Gleason score 4+3 tumors had an increased risk of progression independent of stage and margin status (P <0.0001). The 5-year actuarial risk of progression was 15% and 40% for Gleason score 3+4 and 4+3 tumors, respectively. The mean time to progression was 4.4 years for Gleason score 3+4 tumors and 3.2 years for Gleason score 4+3 tumors. We stratified the patients into four prognostic groups on the basis of organ-confined status, margin status, and Gleason score (3+4 versus 4+3). The 5-year actuarial risk of progression was 10%, 35%, 45%, and 61%, with 10-year progression rates of 29%, 42%, 69%, and 84%, for the four groups. 3.9% of patients with Gleason score 3+4 and 10. 5% with Gleason score 4+3 tumors developed metastatic disease within a mean of 5.7 and 5.6 years, respectively. A Gleason score of 4+3 versus 3+4 was predictive of metastatic disease (P = 0.002) but not local recurrence.
Conclusions: Gleason score 7 tumors are heterogeneous in their biologic behavior. The differences in prognosis for patients with Gleason scores 3+4 and 4+3 tumors at radical prostatectomy are significant. Although the assessment of the percentage of pattern 4 at radical prostatectomy is not likely to be reproducible, the distinction between Gleason score 3+4 and 4+3 should be easier for pathologists to perform.