Robot-assisted radical prostatectomy (RARP) for localized prostate cancer (PCa) confers effective five-year biochemical control of the disease, according to researchers.
Mani Menon, MD, of the Vattikuti Urology Institute, Henry Ford Hospital, Detroit, and colleagues studied 1,384 men with localized PCa who underwent RARP between September 2001 and May 2005. The cohort had a median follow-up of 60.2 months. The men had moderately aggressive PCa: 49% had intermediate- or high-risk disease on biopsy based on D’Amico criteria; 60.9% had Gleason 7-10 disease and 25.5% had T3 or greater disease on final pathology.
The researchers observed 189 cases of biochemical recurrence (BCR), defined as a serum PSA level of 0.2 ng/mL or higher with a confirmatory value. Metastatic disease developed in 13 patients and seven died from PCa, for a metastatic rate and cancer-specific death rate of 2 patients and 1 patient per 1000 patient-years of follow-up, according to study findings published online in European Urology.
At three, five, and seven years, the actuarial BCR-free survival (BCRFS) was 96.8%, 95.1%, and 92.6% in the low-risk patients, 86.7%, 80.2%, and 69.8% in the intermediate-risk patients, and 78.2%, 72.0%, and 67.5% in the high-risk patients, respectively.
In the patients who experienced BCR, the median time to recurrence was 20.4 months. In addition, 65% of recurrences occurred within three years and 86.2% within five years.
The strongest predictors of BCR were pathologic Gleason score 8-10 and pathologic stage T3b/T4. In multivariate analysis, compared with a pathologic Gleason score of 6, those with a Gleason score of 8-10 had a 5.37 increased likelihood of BCR. Patients with pathologic stage T3b/T4 had a 2.71 times increased likelihood of recurrence compared with men who had pathologic stage T2.
In their discussion of study strengths, the investigators noted that their study, to the best of their knowledge, provides the longest follow-up of the largest number of patients treated with RARP. The study also had excellent follow-up: only 7.9% of patients did not report postoperative PSA values. In addition, no patient received secondary treatment until documented BCR, “so this study gives an excellent portrayal of the natural history of localized PCa treated with surgery as the single modality.”
They also pointed to study limitations, including patient selection. The surgeons in the study preferentially treated patients with D’Amico moderate to high risk disease. Moreover, the authors noted that although the five-year median follow-up “is long enough to draw meaningful conclusions about BCR, it is too short to opine about metastasis- and cancer-specific survival.”