A systematic review of the volume-outcome relationship for radical prostatectomy.

CONTEXT: Due to the complexity and challenging nature of radical prostatectomy (RP), it is likely that both short- and long-term outcomes strongly depend on the cumulative number of cases performed by the surgeon as well as by the hospital.
OBJECTIVE: To review systematically the association between hospital and surgeon volume and perioperative, oncologic, and functional outcomes after RP. EVIDENCE ACQUISITION: A systematic review of the literature was performed, searching PubMed, Embase, and Scopus databases for original and review articles between January 1, 1995, and December 31, 2011. Inclusion and exclusion criteria comprised RP, hospital and/or surgeon volume reported as a predictor variable, a measurable end point, and a description of multiple hospitals or surgeons. EVIDENCE SYNTHESIS: Overall 45 publications fulfilled the inclusion criteria, where most data originated from retrospective institutional or population-based cohorts. Studies generally focused on hospital or surgeon volume separately. Although most of these analyses corroborated the impact of increasing volume with better outcomes, some failed to find any significant effect. Studies also differed with respect to the proposed volume cut-off for improved outcomes, as well as the statistical means of evaluating the volume-outcome relationship. Five studies simultaneously compared hospital and surgeon volume, where results suggest that the importance of either hospital or surgeon volume largely depends on the end point of interest.
CONCLUSIONS: Undeniable evidence suggests that increasing volume improves outcomes. Although it would seem reasonable to refer RP patients to high-volume centers, such regionalization may not be entirely practical. As such, the implications of such a shift in practice have yet to be fully determined and warrant further exploration.