European Urology

Hu JC, Gu X, Lipsitz SR, et al
JAMA 2009;302:1557–64
Expert's summary:

Hu et al compared postoperative 30-d complications, long-term incontinence and erectile dysfunction, and anastomotic stricture at 31–365 d postoperatively after minimally invasive radical prostatectomy (MIRP) or open retropubic radical prostatectomy (RRP) using US Surveillance, Epidemiology, and End Results–Medicare linked data.

The study included 1938 men who underwent MIRP and 6899 men who underwent RRP between 2002 and 2007 in several centers in the United States. Analyses showed that men undergoing MIRP versus RRP experienced shorter length of hospital stay; were less likely to receive heterologous blood transfusions; and were at lower risk of postoperative respiratory complications, miscellaneous surgical complications, and anastomotic strictures. In contrast, men undergoing MIRP versus RRP experienced more genitourinary complications and were more often diagnosed as having incontinence and erectile dysfunction, even after adjusting for differences in baseline rates of these conditions. However, no difference in rates of procedures to improve incontinence or erectile dysfunction was observed. Furthermore, the authors concluded that men undergoing MIRP versus RRP experienced similar postoperative use of additional cancer therapies.
Expert's comments:

Laparoscopic radical prostatectomy, either with or without robotic assistance, has become an accepted surgical approach for treatment of localized carcinoma of the prostate. It is based on the hypothesis that, when compared to RRP, these procedures minimize trauma to the periprostatic tissue and allow precise dissection along the prostatic capsule, providing improved functional outcomes for continence and potency while allowing complete surgical excision of all prostatic tissue. Therefore, many patients and physicians intuitively assume that minimally invasive techniques show reduced complications when compared with conventional open operations. This assumption is confirmed by this paper, which showed that among all men undergoing radical prostatectomy in the study, the use of MIRP increased almost 5-fold, from 9.2% in 2003 to 43.2% in 2006–2007.

We can conclude with the authors that MIRP reduces perioperative blood loss, postoperative hospital stay, and short-term complications in comparison to RRP because, in line with the current study, virtually all published reports have shown these reductions when comparing MIRP and RRP [1], [2], and [3].

In these “words of wisdom,” the reported frequency of urinary incontinence and erectile dysfunction after MIRP and RRP are discussed in more detail. These reported frequencies are striking because they are remarkably higher compared to the reported frequencies after most radical prostatectomy series from centers of excellence. These reports from centers of excellence all reported on one operative technique and showed similar rates for long-term continence (all >90%) and potency (40–67%) with MIRP or RRP [2], [3], [4], and [5]. Some suggested that MIRP is superior to RRP with respect to long-term functional postoperative outcomes.

The paper by Hu et al includes comparative data from multiple centers in the United States. Likely due to the study design, the observed results compare unfavorably to the reported postoperative functional outcomes after an RRP and an MIRP in the centers of excellence. It is possible that the observed difference in this study may be due to the learning curve and the relative increase in rates of MIRP versus RRP surgical techniques during the observation period. It is known that the learning curve for the MIRP approach is estimated to be at least 150 to 250 cases, with better outcomes for centers with greater surgeon volumes. Therefore, it is likely that MIRP is not superior to RRP in the return of urinary continence and erectile function during the learning curve and that, probably, the impact of a surgeon's skills and experiences may more important than choosing between MIRP and RRP. Therefore, patients should be informed about the postoperative incidence of urinary incontinence and erectile dysfunction based on the data of individual surgeons and of multicentre studies, not only on the basis of data from centers of excellence. Furthermore, patients should be adequately informed about the benefits of MIRP versus RRP based on valid comparisons, like this study, and should realize that surgeon experience is important when choosing between specific procedures.

This study has some limitations, which were disclosed by the authors. One is that it is possible that men were more likely to be diagnosed as having urinary incontinence and erectile dysfunction following MIRP versus RRP due to observer bias. All study results were based on data from the hospital code system without the use of validated postoperative questionnaires. Therefore, a randomized controlled trial is indicated for comparing outcomes, using validated quality-of-life instruments, following MIRP and RRP. In the meantime, outcomes of valid comparisons, such as this study, will remain of importance to ensure that we are offering patients the optimal treatment and not the latest “marketing trend.”

Conflicts of interest

The author has nothing to disclose.