RESUMO
BACKGROUND: Active surveillance (AS) is a viable management option for approximately 50% of men who are newly diagnosed with prostate cancer. To the authors' knowledge, no direct comparisons between the different variants of AS protocols have been conducted to date. The authors developed a microsimulation decision model to evaluate which of 3 alternative AS protocols is optimal for men with low-risk prostate cancer, and compared each of these with immediate treatment. METHODS: Men who were diagnosed with low-risk prostate cancer at age 65 years were modeled as having been treated with either immediate therapy or via each of 3 AS protocols. Modeled AS protocols represent those in the literature; a modified AS protocol was included in a sensitivity analysis. Immediate therapy included radical prostatectomy, external-beam radiotherapy, or brachytherapy. Outcome measures were quality-adjusted life-years (QALYs) and costs. Cost-effectiveness analysis and deterministic and probabilistic sensitivity analyses were performed. RESULTS: Immediate therapy produced fewer QALYs than all variants of AS. Of the AS protocols evaluated, biennial biopsy was found to be the only efficient option, with an incremental cost-effectiveness ratio of $3490 per QALY compared with immediate therapy. It delayed the need for curative therapy by a mean of 56 months, and was found to be preferred in >86.9% of cases in probabilistic sensitivity analysis. A modified version of low-intensity AS dominated all other options. CONCLUSIONS: For a 65-year-old man with low-risk prostate cancer, AS with biennial biopsy appears to be highly cost-effective compared with common alternatives. An AS protocol using triennial biopsy was found to dominate all other strategies and should be considered for men who are comfortable with a longer period between biopsies. The optimal strategy depends on a patient's tolerance for periodic biopsies and comfort with delaying radical treatment. Physicians should incorporate these patient preferences into decision making.