In a study to determine the surgical learning curve for robotic-assisted laparoscopic radical prostatectomy (RALP) operations, a retrospective analysis of the results of nearly 3,800 procedures showed that it took more than 1,600 prostate cancer surgeries for surgeons to become proficient at the RALP procedure and be able to remove the cancerous prostate consistently with its edges clear of cancer.

RALP is a relatively new technology that has several advantages over typical laparoscopic surgery, which uses awkward "chopstick-like" instruments. RALP provides surgeons with 3-dimensional vision, improved magnification, hand tremor filtering, and a range of motion similar to the human wrist.

"The robotic platform has been shown to take less training time to learn to safely perform prostate cancer surgery compared to its open and laparoscopic surgery counterparts, but we see that becoming expert at the robotic operation takes much longer than just simply developing a base level of competence," said lead author Prasanna Sooriakumaran, M.D., Ph.D., a visiting fellow in urology at the Weill Cornell Medical College in New York. "This research shows that optimizing patient outcomes in terms of positive margin rates takes much more experience. In this regard the operation is more difficult than previously thought."

Dr. Sooriakumaran and his colleagues reviewed the surgical results of 3,794 patients who underwent RALP over a six-year period between 2003 and 2009 in procedures performed by three surgeons from the University of Pennsylvania, Karolinska Institute and Cornell University. The researchers determined mean overall PSM rates and operation lengths for each surgeon at intervals of every 50 operations. The investigators found that the positive surgical margin (PSM) rates for all patients continued to improve with increasing surgeon experience. It took more than 1,600 cases to achieve a PSM rate of less than 10 percent, which is considered a standard goal for such surgeries.

"Even for those who do hundreds of cases per year, it takes a long time to get to the stage where they are getting the best possible cancer control results," Dr. Sooriakumaran said. "Our results show that it is possible to get good cancer cure rates and low surgical margins with this operation, but it takes a significant amount of experience."

The investigators recommended that this type of radical prostatectomy procedure be performed by surgeons who see large volumes of patients.