Existence de grade 5 sur pièce de prostatectomie totale : facteur de mauvais pronostic associé à une moindre survie sans récidive biologique

Abstract

To analyze the impact of the existence of Gleason grade 5 on the adverse pathology and biochemical recurrence-free survival of patients. Three hundred and seventy-two prostatectomies were performed between 1999 and 2011 in our institution for localised prostate adenocarcinoma. We examined the existence of grade 5 of the specimen to determine the reliability of prostate biopsies in the diagnosis of grade 5 and the association of grade 5 with other histoprognostic factors. Biochemical recurrence-free survival was analyzed according to the presence of grade 5 in the final specimen. In total, all histological data and biochemical recurrence-free survival were available for 321 patients who were included in the study. Sixty-eight had Gleason grade 5 (majority or third minority pattern) on the specimen while 253 had not. Grade 5, rarely diagnosed on biopsy (sensitivity=26.47 %) was correlated independently with the extracapsular extension (OR=2.1; CI 95 [1.1-3.9]), the seminal vesicle invasion (OR=3.8; CI 95 [1.7-8.7]) and positive surgical margins (OR=2.0; CI 95 [1.1-3.6]). Overall survival was similar in both groups but the biochemical recurrence-free survival was statistically lower in the presence of grade 5 (HR=3.7; CI 95 [1.8-7.6]). Biochemical recurrence-free survival was not different than grade 5 is predominant or third minority pattern (HR=1.01; CI 95 [0.3-2.8]). On multivariate analysis, grade 5 was an independent risk factor for biochemical recurrence (P=0.005) as well as seminal vesicle invasion (P=0.047). The existence of grade 5 in the surgical specimen whatever the percentage was a poor prognostic factor associated with increased tumor aggressiveness and reduced biochemical recurrence-free survival. 5.