medwireNews: Active surveillance (AS) is an effective way of monitoring patients with low-risk prostate cancer and is associated with a low risk for systemic progression, say researchers.
In a retrospective, 60-month study of 262 men undergoing AS who would otherwise have been considered for immediate surgery or radiation therapy, only 43 eventually opted for treatment.
And of those who chose to undergo this postponed treatment, almost all (95%) are currently without evidence of metastases almost 2 years later, report Bertrand Guillonneau (Memorial Sloan-Kettering Cancer Center, New York) and colleagues.
"These findings highlight many of the hallmark features and purported benefits of AS in that most men will not require an intervention, and those who do will have benefited from a period when quality of life and cancer related outcomes do not appear to be compromised," says the team.
However, a restaging biopsy before considering AS seems to be essential as the presence of cancer and the number of cancerous cores detected this way influenced the likelihood for patients remaining on AS, notes the team.
The ultimate success of any AS program relies on accurate disease characterization at diagnosis, write Guillonneau et al. By specifying strict inclusion criteria (age ≤75 years, clinical stage T1-T2a, prostate specific antigen 10 ng/mL or less, 3 or fewer positive cores at diagnostic biopsy, biopsy Gleason score ≤6) and requiring a restaging biopsy before commencing AS, the team identified a cohort of men at low risk for disease progression and an estimated 5-year biochemical recurrence risk of less than 5% if they opted for immediate prostatectomy.
As reported in the Journal of Urology, the 2- and 5-year probability of the men remaining on AS was 91% and 75%, respectively.
Of the 43 men who elected to have active treatment with radical prostatectomy (n=26), radiation therapy (n=13), cryotherapy (n=1), or androgen deprivation therapy (n=3), only two had disease progression at a median of 23 months following treatment.
Patients in whom cancer was detected on the repeat biopsy and those who had a higher versus lower total number of positive cores from the diagnostic and repeat biopsies combined were significantly more likely to discontinue AS and opt for treatment.
"We strongly believe that a restaging biopsy before initiating AS is mandatory as it excludes up to 30% of patients considered for AS based on the initial diagnostic biopsy, minimizes the risk of a Gleason grade sampling error and predicts the likelihood of remaining on AS," says the team.
"Our view on AS is not one of disregard for men with low risk cancer features but rather a strategy that encourages initial observation, frequent monitoring based on serial prostate biopsies and, if needed, the implementation of active therapy while disease is still at a highly curable stage," write Guillonneau et al.