Various traits define a competent surgeon, including such characteristics as acute tactile sense, excellent manual dexterity, and a particularly discerning eye for anatomical subtleties and for where and how to cut tissue.
Nowhere are such characteristics more important than in the performance of the radical prostatectomy (RP). But how much does experience, as measured by the number of RPs performed, matter?
Mounting evidence suggests that experience is an important contributor to outcomes. For example, based on a recent review, researchers at Vanderbilt University Medical Center in Nashville, Tenn., led by Daniel A. Barocas, MD, found a “pervasive association” between higher hospital RP case volume and improved outcomes, according to report in Urologic Oncology (2009; published online ahead of print). “Increasing individual surgeon volume may also portend better outcomes, not only perioperatively but even with respect to long-term cancer control and urinary function,” the authors wrote.
In another study, a team, led by Andrew J. Vickers, PhD, of Memorial Sloan-Kettering Cancer Center (MSCC) in New York, showed that a typical patient undergoing RP with a surgeon who reached a learning curve plateau of 250 prior RPs had a 10.9% risk of recurrence at five years compared with a 17.7% rate for men treated by a surgeon who had performed only 10 such procedures previously, according to a report in the Journal of the National Cancer Institute (2007;99:1171-1177).
The learning curve for open radical prostatectomy—the point at which recurrence rates started falling—started to flatten when the surgeon hit 250 operations, although for organ-confined disease “the learning curve continues to lead to improving results until well more than 1,000 surgeries,” the authors wrote. For laparoscopic surgery, the curve “really didn’t flatten at all,” Dr. Vickers, an associate attending research methodologist, told Renal & Urology News. “It very, very slowly increased up to about 750 prior surgeries.”
Few surgeons, however, perform anywhere near this many RPs in the course of their career. In fact, in a study published recently in the Journal of Urology (2009;182:2677-2681), Dr. Vickers and an MSCCC colleague, Caroline J. Savage, MPH, found that 82.9% of 933 surgeons surveyed perform 10 or fewer RPs per year. They concluded that low annual RP caseloads likely result in poorer outcomes.
Dr. Vickers emphasized that “250 is not an absolute cut point. It doesn’t mean that above it, you’re fine, and below it, you’re useless.” He added: “It seems intuitive that there are some good surgeons with low volume/low experience, and there are some highly experienced surgeons who are just repeating the same mistakes over and over again.”
Does practice make perfect?
David Y.T. Chen, MD, Director of the Urologic Oncology Fellowship Program at Fox Chase Cancer Center in Philadelphia, said he does not believe 250 RPs is a magic threshold for defining competence, but “intuitively, it makes sense to have a number indicating when somebody becomes good or excellent or outstanding. This is not necessarily unique to radical prostatectomy or urology or surgeons. Like anything else humans do, practice makes perfect.”
Charles J. Rosser, MD, MBA, Section Chief of Urologic Oncology at the M.D. Andersen Cancer Center branch in Orlando, Fla., has a different view. “Practice doesn’t make perfect. Practice makes permanent,” he declared. “So if someone does 250 surgeries poorly, the 251st surgery is likely to be poor as well.”
This is not to say an observant mind cannot learn something with routine practice, Dr. Rosser conceded. “We must look more at outcomes than at volumes,” he said. “Favorable outcomes are the ultimate goal.”
Dr. Rosser coauthored a paper in BMC Surgery titled, “Radical Prostatectomy: Hospital Volumes and Surgical Volumes – Does Practice Make Perfect?” (2009; published online ahead of print). His group found that most of the 307 urologists surveyed were in favor of requiring surgeons to meet a minimum volume threshold (MVT) for difficult procedures. The urologists assigned the lowest MVTs to the most complex surgeries.
For example, RP was rated only the third most complex surgery, but was given the highest MVT (more than 20 per year). In contrast, radical cystectomy with continent urinary diversion had the lowest MVT (one to five per year).
According to Dr. Rosser, items that should factor in to calculating MVT include, but are not limited to:
- percentage of urologists performing (or who can perform) the operation
- reported complication rates (intraoperatively and postoperatively), including erectile dysfunction, incontinence, tumor control
- reported length of stay
- estimated blood loss
- transfusion rates