Stratification of high-risk prostate cancer into prognostic categories: A European multi-institutional study - Abstract

BACKGROUND: High-risk prostate cancer (PCa) is an extremely heterogeneous disease.

A clear definition of prognostic subgroups is mandatory.

OBJECTIVE: To develop a pretreatment prognostic model for PCa-specific survival (PCSS) in high-risk PCa based on combinations of unfavorable risk factors.

DESIGN, SETTING, AND PARTICIPANTS: We conducted a retrospective multicenter cohort study including 1360 consecutive patients with high-risk PCa treated at eight European high-volume centers.

INTERVENTION: Retropubic radical prostatectomy with pelvic lymphadenectomy.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Two Cox multivariable regression models were constructed to predict PCSS as a function of dichotomization of clinical stage (< cT3 vs cT3-4), Gleason score (GS) (2-7 vs 8-10), and prostate-specific antigen (PSA; ≤ 20 ng/ml vs >20 ng/ml). The first "extended" model includes all seven possible combinations; the second "simplified" model includes three subgroups: a good prognosis subgroup (one single high-risk factor); an intermediate prognosis subgroup (PSA >20 ng/ml and stage cT3-4); and a poor prognosis subgroup (GS 8-10 in combination with at least one other high-risk factor). The predictive accuracy of the models was summarized and compared. Survival estimates and clinical and pathologic outcomes were compared between the three subgroups.

RESULTS AND LIMITATIONS: The simplified model yielded an R2 of 33% with a 5-yr area under the curve (AUC) of 0.70 with no significant loss of predictive accuracy compared with the extended model (R2 : 34%; AUC: 0.71). The 5- and 10-yr PCSS rates were 98.7% and 95.4%, 96.5% and 88.3%, 88.8% and 79.7%, for the good, intermediate, and poor prognosis subgroups, respectively (p=0.0003). Overall survival, clinical progression-free survival, and histopathologic outcomes significantly worsened in a stepwise fashion from the good to the poor prognosis subgroups. Limitations of the study are the retrospective design and the long study period.

CONCLUSIONS: This study presents an intuitive and easy-to-use stratification of high-risk PCa into three prognostic subgroups. The model is useful for counseling and decision making in the pretreatment setting.

Written by:
Joniau S, Briganti A, Gontero P, Gandaglia G, Tosco L, Fieuws S, Tombal B, Marchioro G, Walz J, Kneitz B, Bader P, Frohneberg D, Tizzani A, Graefen M, van Cangh P, Karnes RJ, Montorsi F, Van Poppel H, Spahn M.   Are you the author?
Department of Urology, University Hospitals, Leuven, Belgium; San Raffaele Scientific Institute, Urological Research Institute, Department of Urology, Milan, Italy; Department of Urology, University of Turin, Turin, Italy; Department of Biostatistics, University Hospitals, Leuven, Belgium; Department of Urology, Université Catholique de Louvain, Brussels, Belgium; Department of Urology, University of Piemonte Orientale, Novarra, Italy; Department of Urology, University Medical Centre Eppendorf, Hamburg, Germany; Department of Urology, Julius Maximilians Universität Würzburg, Würzburg, Germany; Department of Urology, Community Hospital Karlsruhe, Karlsruhe, Germany; Department of Urology, Mayo Clinic, Rochester, MN, USA; Department of Urology, University of Bern, Bern, Switzerland.

Reference: Eur Urol. 2014 Jan 25. pii: S0302-2838(14)00071-2.
doi: 10.1016/j.eururo.2014.01.020


PubMed Abstract
PMID: 24486307

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