Prostatectomy found efficacious in high-risk prostate cancer

May 1, 2012

The authors of a study reported cancer-specific and overall survival rates of 96% and 94%, respectively, at 5 years in men with high-risk prostate cancer who underwent radical prostatectomy.

Key Points

Berlin-Along with the changing models for the treatment of high-risk localized prostate cancer over the years have come better treatment outcomes. While the dominant paradigm a decade ago was to treat high-risk disease with androgen deprivation and radiation therapy, today, radical prostatectomy has gained momentum.

Most recently, the authors of a study from the University of New South Wales, Sydney, Australia, reported cancer-specific and overall survival rates of 96% and 94%, respectively, at 5 years in men with high-risk prostate cancer who underwent radical prostatectomy.

"Radical prostatectomy is an effective treatment in high-risk disease, with more than 50% likelihood of long-term cancer control, either alone or in combination with salvage radiation therapy," said first author Paul Cozzi, MBBS, senior lecturer at the University of New South Wales.

The D'Amico classification stratifies patients with prostate cancer into those with low, intermediate, or high risk of biochemical recurrence after surgery, according to the clinical TNM stage, biopsy Gleason score, and preoperative PSA level.

The study participants had a median age of 63 years (range, 44-78 years). Median PSA was 7.2 ng/mL (0.15-42 ng/mL), and the mean PSA was 9.4 ng/mL (17 patients had PSA <4.0 ng/mL, seven had PSA <2.5 ng/mL, and 14 had PSA >20.0 ng/mL).

Ten patients had T1c disease, while 155 patients had T2c or higher clinical staging. Gleason 6 was seen in 36 patients, Gleason 7 in 101 patients, and Gleason 8-10 was observed in 73 patients.

For the analysis, ultrasensitive PSA ≥0.2 ng/mL was considered biochemical relapse. Salvage radiation was administered to 10% of patients, 65% of whom achieved a durable biochemical response.

"One of the strengths of this series is that ultrasensitive PSA was used for follow-up and therefore very careful monitoring of patients was undertaken, with PSA performed every 6 months," observed Dr. Cozzi, who presented the results at the 2011 Société Internationale d'Urologie congress in Berlin.

The authors identified organ-confined (pT2) disease in 53% of patients, all of whom had clear surgical margins and did very well after surgery.

Clear surgical margins key

"We tried very hard in these patients to challenge the dominant paradigm of androgen deprivation and radiation therapy. To achieve this, we needed to get clear surgical margins in these patients," he noted.

The positive surgical margin rate was 33% in pT3 disease (extracapsular extension), of which 12% had extensive and 21% had focal margins. Eighty-one percent of patients with positive surgical margins had undergone nerve-sparing surgery. By contrast, pT2 patients had clear margins.

Seminal vesicle or positive lymph node involvement was observed in 16% and 7% of patients, respectively. Salvage radiation was administered to 10% of patients, with a durable biochemical response achieved in 65% of these.

The biochemical-free survival was 71% in patients with PSA <0.2 ng/mL and 58% with PSA <0.1 ng/mL at 5 years. Dr. Cozzi noted no difference between nerve-sparing or non-nerve-sparing procedures (p=.85).

Recurrences were seen in 46.2% of patients with a positive surgical margin versus 20.4% of patients without positive margins (p=.0016). As expected, positive margins were significantly associated with poor outcomes, Dr. Cozzi noted. In patients with organ-confined disease, the recurrence rate was 12.8% versus 43.9% in those whose disease whose disease had spread beyond the prostate (p≤.0001).

Ninety percent of the patients were security liner pad-free, and 5% required further surgical intervention (male sling or bio-injectable). Potency was preserved in 74% of patients undergoing bilateral nerve-sparing surgery and in one-third using phosphodiesterase type-5 inhibitors.