Not all Gleason pattern 4 prostate cancers are created equal: A study of latent prostatic carcinomas in a cystoprostatectomy and autopsy series - Abstract

BACKGROUND: The Gleason grading system represents the cornerstone of the management of prostate cancer.

Gleason grade 4 (G4) is a heterogeneous set of architectural patterns, each of which may reflect a distinct prognostic value.

METHODS: We determined the prevalence of the various G4 architectural patterns and intraductal carcinoma (IDC) in latent prostate cancer in contemporary Russian (n = 220) and Japanese (n = 100) autopsy prostates and in cystoprostatectomy (CP) specimens (n = 248) collected in Italy. We studied the association of each G4 pattern with extraprostatic extension (EPE) and tumor volume to gain insight into their natural history. Presence of IDC and nine architectural features of Gleason grade 4 and 5 cancer were recorded.

RESULTS: The prevalence of Gleason score ≥7 PC was higher in the autopsy series (11%) compared to the CP series (6.5%, P = 0.04). The prevalence of IDC and carcinoma with a cribriform architecture was 2.2% and 3.4% in the autopsy series and 0.8% and 3.6% in the cystoprostatectomy series, respectively. In multivariable analysis, cribriform architecture was significantly associated with increased tumor volume (P < 0.001) and EPE (OR:11.48, 95%CI:2.30-57.16, P = 0.003). IDC was also significantly associated with EPE (OR:10.08, 95%CI:1.58-64.28, P = 0.014). Small fused glands had a strong negative association with EPE in the autopsy series (OR:0.06, 95%CI:0.01-0.58, P = 0.015).

DISCUSSION: Our study revealed that in latent prostate cancer both cribriform architecture and IDC are uniquely associated with poor pathological outcome features. In contrast, Gleason score 7 (3 + 4) cancers with small-fused gland pattern might possibly include some prostate cancers with a more indolent biology.

Written by:
Siadat F, Sykes J, Zlotta AR, Aldaoud N, Egawa S, Pushkar D, Kuk C, Bristow RG, Montironi R, van der Kwast T.   Are you the author?
Department of Anatomical Pathology, Royal Alexandra Hospital, Edmonton, Alberta, Canada; Biostatistics, Princess Margaret Cancer Center, Toronto, Ontario, Canada; Department of Surgery, Division of Urology, Mount Sinai Hospital and Princess Margaret Cancer Center, University Health Network, Toronto, Ontario, Canada; Department of Pathology and Microbiology, Jordan University of Science and Technology, Irbid, Jordan; Department of Urology, Jikei University School of Medicine, Tokyo, Japan; Department of Urology, University of Moscow, Moscow, Russia; Department of Radiation Oncology, Princess Margaret Cancer Center, University Health Network, Toronto, Ontario, Canada; Institute of Pathological Anatomy, Polytechnic University of the Marche Region, School of Medicine, United Hospitals, Ancona, Italy; Department of Laboratory Medicine and Pathology, University Health Network, Toronto, Ontario, Canada.

Reference: Prostate. 2015 May 11. Epub ahead of print.
doi: 10.1002/pros.23009

PubMed Abstract
PMID: 25963383 Prostate Cancer Section