Man or machine? Da Vinci robot has no advantage.
More disadvantages after robot-assisted surgery than previously assumed
Nerve maintenance, less incontinence and shorter laytimes. Robot-assisted surgery to remove the prostate gland is becoming increasingly popular. But can the advantages that have been propagated actually be confirmed? Two major US studies on patients treated with the "DaVinci" method show the advantages and disadvantages of modern surgical techniques.
The worldwide distribution of the DaVinci robot was rapid. After only two years, numerous clinics and prostate centres now have the modern surgical technique at their disposal despite the enormous initial investment costs. In contrast to retropubic (belly incision) and perineal (abdominal incision) radical removal of the prostate, access is through skin incisions of a few millimetres in size. The surgeon does not sit directly on the patient but on a console and controls the four robot arms with the surgical instruments. An impressive 3D view, 10x magnification and high-precision instrument guidance promise patients with prostate cancer gentle treatment, fewer complications and very good healing rates. The advantages of the high-tech surgical method include shorter hospital stays, a lower risk of bleeding and a smaller surgical scar. In addition, the robot-assisitized surgical technique promises less impotence and urinary incontinence due to the precise guidance of the surgical instruments.
Not all that glitters is gold,"says Dr. Stephan Neubauer, urologist at the West German Prostate Center. The aim of therapy for localized prostate cancer should still be to achieve a good oncological outcome and as few side effects as possible. This means: Few PSA recurrences (return due to a renewed increase in PSA), maintenance of continence (ability to hold urine) and potency (erectility).
However, two US studies1/2 now give rise to doubts that the robot-assisted operation will actually meet expectations. Although both studies showed a reduction in blood transfusion and shorter periods of rest, the results with regard to survival rate, continence and potency were worse than with the conventional surgical technique. For example, a survey1 of 2700 prostate cancer patients showed that within the first six months after robot-assisted surgery, the rate of further treatment (e. g. radiation therapy) of the so-called prostate cancer patients was significantly higher. Salvage therapy was three times higher (27.8% vs. 9.1%) and the likelihood of anastomosis stricture (narrowing of the urethra due to increased scarring) was 1.4 times higher than in conventional prostate surgery. In a similar analysis, it was also found that incontinence and erectile dysfunction were even more frequent after the minimally invasive entry. Here it becomes clear that in addition to the advertised advantages such as lower blood loss and shorter waiting times, in the medium term there may also be disadvantages.
Away from surgery to radiation
According to Neubauer, the fact that radical removal of the prostate gland, with or without robots, is still considered by many doctors in Germany as the only successful treatment option for prostate cancer has long since become obsolete. Numerous studies4 have shown that in patients whose tumor is limited to the prostate, brachythe-therapy (inner radiation) achieves the same healing rates with fewer side effects. Long-term studies, including a recent US study, show that erectile dysfunction occurs after radical surgery at 70 percent and after seed implantation at 14 percent4. Urinary incontinence, which is up to 50 percent after radical removal of the prostate, is also negligible at 0.3 to 3 percent after seed implantation and only occurs after prior removal of the prostate (TURP).
Therefore, Neubauer sums up, rather, whether irradiation is preferable to radical surgery. "But despite the excellent long-term results of brachytherapy, many patients have high expectations of robotic technology and are willing to undergo treatment using the DaVinci method without any real benefit being proven."
Hu JC, gold KF, Pashos CL et al: Utilization and outcomes of minimally invasive vs. open radical prostatectomy. J Clin Oncol 2008 26 (14): 2278-2284
Hu JC, gold KF, Pashos CL et al: Comparative effectiveness of minimally invasive vs open radical prostatectomy. JAMA 2009 302 (14): 1557-1564
Chen R. C., Clark J. A.; Talcott J. A.: Individualizing Quality-of-Life Outcomes Reporting