Robot-assisted radical prostatectomy (RARP) confers excellent long-term control of prostate cancer (PCa), according to a study of what researchers believe is the largest series to date to look at oncologic outcomes after RARP.
The study, by investigators at the Henry Ford Health System’s Vattikuti Urology Institute in Detroit, included 4,803 of 5,152 patients who underwent RARP at the institute from 2001 to 2010. After a median follow-up of 26.4 months, biochemical recurrence (BCR) occurred in 470 patients (9.8%) and metastatic disease developed in 31 patients (0.7%); 13 patients died from prostate cancer (0.3%).
Results also showed that the actuarial 8-year BCR-free survival (BCRFS), metastasis-free survival (MFS), and cancer-specific survival (CSS) rates were 81%, 98.5%, and 99.1%, respectively, the investigators reported in BJU International (2014;114:824–831). Among men with node-positive disease, the actuarial 5-year BCRFS, MFS, and CSS rates were 26%, 82%, and 97%, respectively.
“This evaluation represents the largest of its kind and conclusively establishes that the long-term oncological outcomes following RARP are at par with the outcomes following other modalities of radical prostatectomy,” corresponding author Akshay Sood, MD, told Renal & Urology News.
The study cohort had a mean age of 60 years and a preoperative PSA level of 6.1 ng/mL. Dr. Sood’s group defined BCR as a post-operative serum PSA level of 0.2 ng/mL or higher with a confirmatory value (a PSA value higher than 0.2 ng/mL at 2 different follow-ups).
The investigators also identified predictors of BCR, which included preoperative PSA level, surgical margin status, and pathologic primary Gleason score. For example, among patients with organ-confined disease, patients with a preoperative PSA level of 10–20 ng/mL had a significant 2.4 times greater hazard of BCR than those with a level of 10 ng/mL or less. Patients with a positive surgical margin (PSM) had a significant 3.8 times greater hazard of BCR compared with those who had a negative surgical margin. Compared with patients who had a pathologic primary Gleason score of 3, those with a score of 5 had a significant 5.5 times greater hazard of BCR.
Previous studies have shown that RARP may offer good PCa control. In a retrospective population-based study of PCa patients published in European Urology (2014;66:666–672), Jim C. Hu, MD, MPH, of the University of California Los Angeles (UCLA), and Maxine Sun, PhD, of the University of Montreal Health Center, used Surveillance Epidemiology and End Results (SEER)-Medicare linked data to study 5,556 men who underwent RARP and 7,878 who underwent open radical prostatectomy (ORP). In propensity-score adjusted analyses, RARP was associated with a significant 34% and 30% decreased likelihood of PSMs compared with ORP among men with intermediate- and high-risk cancer, respectively.
Additionally, results showed that RARP was associated with a 25%, 27%, and 33% decreased likelihood of requiring additional cancer treatment (androgen deprivation and radiation) within 6, 12, and 24 months, respectively.
RARP has become the predominant radical surgery approach for PCa in the United States with nearly 60%-80% of the surgical candidates undergoing this approach, according to a report in Surgical Endoscopy (2013;27:2253–2257). For the surgeon, RARP offers better ergonomics, precise dissection, and better visualization in narrow cavities such as the pelvis, Dr. Sood observed. For patients, RARP offers a lower rate of complications, better urinary and sexual functional outcomes, and improved cosmesis. In addition, patients experience much less post-operative pain and require less pain medication.
He pointed out that several factors should be considered when comparing outcomes among various RP approaches, the foremost being the effect of surgeon volume. It appears that high-volume surgeons have better or equivalent outcomes regardless of surgical approach, he noted.
A recent study showed that high-volume surgeons are the predominant users of RARP. The study, published online ahead of print in BJU International, found that by 2010, 73% of high-volume surgeons adopted RARP compared with 45% and 36% of intermediate- and low-volume surgeons. The investigators defined low-, intermediate, and high-volume surgeons as those performing fewer than 5, 5-24, and more than 24 RPs annually, respectively. The retrospective study, by Steven L. Chang, MD, of Harvard Medical School in Boston, and colleagues, included 489,369 men who underwent open or laparoscopic RP or RARP from 2003 to 2010.