Prognostic influence of the third Gleason grade in prostatectomy specimens

Gleason grading of prostatic specimens remains as one of the most powerful factors predicting prognosis in patients with prostate cancer. This grading system was created by Donald Gleason about 49 years ago and it takes into account the 2 most prevalent grades in the tumor sample, but it does not consider the presence of a third high grade pattern when it represents less than 5% of the whole radical prostatectomy specimen.

The objective of the present study is to determine whether the existence of a third pattern of growth in the radical prostatectomy samples correlates with a shorter recurrence free survival.

We have reviewed 85 consecutive specimens of radical prostatectomy from patients with clinical localized disease. Those who received previous hormonal or radiation therapy were excluded. We have determined the Gleason grade and also the presence of a third higher grade pattern, surgical margins status, capsular, vascular, and lymphatic invasion. We have analyzed whether the existence of this high grade third pattern areas influences prognosis. Recurrence was defined with PSA levels (biochemical recurrence).

We have shown that the presence of a Gleason's grade 5 pattern of growth worsens prognosis in patients with tumors grade 7 (both 3 + 4 and 4 + 3), with a shorter time to recurrence. The latter group of patients behaves more like patients with Gleason 8 tumors. This worse prognosis should be taken into account for patient surveillance and future adjuvant therapies. We feel this information is relevant and should be reported in the pathology reports.