[Prognosis of Gleason 7 (3+4) prostatic adenocarcinoma with a low rate of grade 4 - Retrospective study of 104 cases].

Abstract

Introduction: The aim of this study was to compare the prognosis of Gleason Score (GS) 7 (3+4) prostatic adenocarcinoma with a low percentage of grade 4 to that of GS6 (3+3) prostatic adenocarcinoma.

Methods: All patients with GS6 or GS7 prostatic adenocarcinoma who underwent prostatectomy between 2014 and 2018 were selected. The prostate biopsy (PB) and prostatectomy resection specimen (RS) slides were reviewed by 2 pathologists. A statistical analysis was carried out to evaluate the relationship between the clinical, paraclinical and histological characteristics of the patients on biopsies and prostatectomies with the risk of recurrence.

Results: One hundred and four patients were included. A recurrence occurred in 21 patients (20.2%). In univariate analysis, an association was observed between the risk of recurrence and the GS (P=0.014 for PB / P=0.006 for RS), grade 4 percentage (P=0.020/P=0.002), especially by applying the thresholds of 5% (P=0.008/P=0.018) and 10% (P=0.015/P<0.001), the tumor stage pT (P=0.045), the quality of surgical resection R (P=0.015) and the size of the tumor focus in contact with the limits (P<0.001). In multivariate analysis, grade 4 percentage greater than 10% was associated with the risk of recurrence on biopsy and prostatectomy (respectively OR 4.83 [IC95 1.38; 16.88]; P=0.014 and OR 6.29 [IC95 1.96; 20.20]; P=0.002), as well as R1 resection (OR 3.65 [IC95 1.24; 10.76]; P=0.019 and OR 4.06 [IC95 1.27; 13.03]; P=0.018).

Conclusion: Our study suggests that GS7 (3+4) tumors with less than 10% of grade 4 have a similar prognosis to that of GS6 (3+3) tumors. This could allow some GS7 (3+4) patients to benefit from the active surveillance therapy, instead of undergoing more aggressive treatments such as surgery or radiotherapy.