Active surveillance in PCa, a temporary but indispensable solution
16 Nov 2014 - Joel Vega
With the concern regarding over-diagnosis and unnecessary treatment in indolent prostate cancer, the option to choose active surveillance (AS) has become a clear fallback position and experts say this may well be the case so long as the concern persists and diagnostic biomarkers remain elusive.
“Active surveillance (AS) should be regarded as a temporary but indispensable solution for PSA screening related over-diagnosis and overtreatment,” said Monique Roobol (NL) during the Late Breaking News session at the second day of the 6th European Multidisciplinary Meeting on Urological Cancers (EMUC) in Lisbon, Portugal
Roobol gave an update and overview on current work being done on active surveillance and said AS protocols are based on serial (transrectal) prostate biopsies which are not without risks.
“Prostate cancer is a two-faced disease, and it can be present as a potentially indolent form that during a lifetime will never cause any harm or the disease can follow a very aggressive course causing suffering and death within several years,” said Roobol.
She said the serum prostate specific antigen test or PSA is unfortunately not (aggressive) prostate cancer-specific. But despite this limitation many men with PSA levels regarded as abnormal are referred to further assessment which may lead to overtreatment. Roobol noted that epidemiologic estimates on over-diagnosis are in the range of 22% to 42%. But individual estimate vary considerably and are estimated at 3% to 88%.
“AS cannot help with over diagnosis but can reduce the related harm,” she said, whlet underscoriong that more careful patient selection for screening is essential and that dissociating diagnosis from treatment is crucial to reduce harm.
Roobol said an international AS conference recently met to review scientific manuscripts and studies that have investigated the various issues linked to genetics, biomarkers, role of imaging and other variables in AS. Studies on the role of MRI, for example, examined the questions whether imaging can replace serial prostate biopsy.
She also discussed the group’s conclusions on quality of life issues of men on AS. “The data reflect measurements of the first few years on AS, but no studies were randomized and there is risk of self-selection bias,” Roobol said, and added that QoL is comparable to men undergoing radical treatments.
In her concluding remarks she noted that studies exploring the potential of various biomarkers in AS cohorts are limited. “Imaging data are immature and for now cannot replace serial biopsies,” explained Roobol. She also underscored that current AS protocols world-wide should be continued to collect prospective long-term data on AS.
Another development, according to Roobol, is a global collaboration that was initiated to enable the development of evidence-based guidelines on AS, and which reflects the urgent need for data with regards the value of biomarkers/imaging within an AS setting.