A paper just published in European Urology claims that prostate cancer patients treated with robot-assisted laparoscopic prostatectomy (RALP) recover continence and sexual function faster than those treated with non-robot-assisted laparoscopic surgery (LRP).
Porpiglia et al. report data from a small trial designed to assess a series of outcomes among men diagnosed with localized prostate cancer and randomized to treatment with either RALP or LRP. Outcomes specifically included continence at the time of catheter removal, continence at 48 h after catheter removal, and continence and potency at 1, 3, 6, and 12 months post-surgery.
The core results of this study are as follows:
- The trial included 120 patients.
- 60 men were randomized to treatment with RALP (Group A).
- 60 men were randomized to treatment with LRP (Group B).
- There was no evidence of differences between the patients as regards
- Perioperative outcomes
- Postoperative pathology
- Surgical complication rates
- PSA levels post-surgery
- Continence rates were better for Group A than for Group B “at every time point”.
- At 3 months post-surgery
- 80.0 percent of men in Group A were continent.
- 61.6 percent of men in Group B were continent.
- This difference was statistically significant (p = 0.044).
- At 12 months post-surgery
- 95.0 percent of men in Group A were continent.
- 83.3 percent of men in Group B were continent.
- This difference was statistically significant (p = 0.042).
- Also at 12 months post-surgery
- 80.0 percent of men in Group A had recovered erectile function.
- 54.2 percent of men in Group B had recovered erectile function.
- This difference was statistically significant (p = 0.020).
Now the authors are very clear that one of the limitations of this trial is its small size. The data set would be a good deal more compelling if it had included more like 240 patients than 120. The other issue is the skill levels of the surgeons.
It is well appreciated that it is easier to learn how to do RALPs quite well than it is to learn how to do LRPs quite well. One therefore has to ask whether this study actually reflects a difference in the outcome based on the technology or a difference based on the skill levels (using that technology) of the surgeons carrying out the operations. This is a much harder question to answer.
One other critical factor that is not addressed in the easily accessible data is how the authors were defining acceptable levels of continence and erectile function. We assume that these are defined in the full text of the paper, but we have not seen these definitions.
Supplementary comment as of 3 p.m. Eastern on August 9: A Reuters report on this paper that we had not previously seen makes it clear that all of the 120 surgeries reported were carried out by a single surgeon. The question that arises from this information is therefore why that particular surgeon was able to operate with greater skill using robot-assistance than by using LRP. Again, the data do not necessarily imply that the difference is in fact due to the technology, although they do suggest that some surgeons may be able to obtain superior results using robot assistance compared to a purely laparoscopic approach.