‘AS’ Means Long Periods Without Treatment and No Worsening of Prostate Cancer
by Sarah Guy | Medwire-news.md | 11.03.2009
Active surveillance (AS) for early prostate cancer could prevent the need for active treatment for up to 2 years with no worsening of the condition, study findings suggest.
“AS aims to avoid overtreatment in men with small, localized, well-differentiated prostate cancer, by initially withholding radical treatment,” say Roderick van den Bergh, from Erasmus Medical Center in Rotterdam, The Netherlands, and colleagues.
“Instead, the tumor is closely monitored with the purpose of switching to active local therapy with curative intent if there is progression,” they report in the BJU International.
The first 500 men from the ongoing Prostate Cancer Research International: Active Surveillance (PRIAS) were included in the study. They all had asymptomatic, small, localized, and well-differentiated prostate cancer, a clinical stage of T1 or T2, a prostate-specific antigen (PSA) level of 10.0 ng/ml or less, and a Gleason score of 3+3=6 or more favorable, and had not received previous treatment.
The men underwent PSA testing every 3 months, and digital rectal exams (DRE) every 6 months for the first 2 years after diagnosis, then PSA testing every 6 months and DRE yearly. A biopsy was taken at 1, 4, and 7 years.
The main endpoint of the study was active therapy-free survival (ATFS), with secondary endpoints including reasons for stopping AS.
Men were switched to active therapy if during follow-up they had a PSA doubling time of up to 3 years, a clinical stage more than T2, more than two positive cores after biopsy, or a Gleason score of more than 6.
The overall 2-year ATFS among the cohort was 73%. In all, 82 (16.4%) men stopped AS, of these 83% did so in line with the PRIAS protocol, while 17% stopped on request or due to anxiety.
Of the 261 repeat biopsies available for analysis during follow-up, 34% showed no cancer, while 44% showed cancer that had not worsened. The remaining 22% of biopsies showed unfavorable cancer (more than two positive biopsies, and/or a Gleason score more than 3+3=6).
Adverse PSA doubling times (0–10 years) were similar for men with favorable and unfavorable re-biopsy results, at 53% and 62%, respectively.
The researchers therefore infer from their findings that active surveillance (AS) may prevent over-treatment of men with early prostate cancer. Active therapies are frequently offered and administered to men who will never develop prostate cancer symptoms, they explain, which can put patients at an immediate risk for side effects.
The team concludes: “In the future, PRIAS could provide data to optimize AS protocols, as well as long-term mortality and quality of life outcomes of AS.”
Copyright Medwire-news.md 2009
