From Radical Treatment to Structured Active Surveillance: A Narrative Review of Low-Risk Localized Prostate Cancer

Active surveillance (AS) is the preferred initial strategy for suitable men with confirmed low-risk localized prostate cancer and sufficient life expectancy to benefit from future curative treatment. The objective of this review is to determine which components of contemporary surveillance practice are supported by trial and cohort evidence, which remain adjunctive or investigational, and to integrate this appraisal into an explicit, life-expectancy-aware decision pathway. This narrative review traces the transition from radical treatment through historical conservative management trials to contemporary surveillance. The original search covered literature up to 10 September 2026; supplementary retrieval and verification were performed on 10 October 2026. Evidence is interpreted by population, design and endpoint. Watchful waiting, PIVOT observation and ProtecT active monitoring are distinguished from structured AS. Clinical selection, the exclusion of cribriform/intraductal carcinoma, MRI-informed sampling and protocol-based reassessment underpin surveillance. Stable MRI permits selected biopsy individualization under EAU guidance but does not universally replace histological reassessment. Tissue classifiers and germline findings have heterogeneous prognostic evidence; the reviewed studies do not establish improved outcomes from molecularly guided AS. Selected MRI-based strategies were economically favorable within US models, without demonstrating biopsy-omission safety. Psychological outcomes and reasons for changing treatment vary. Focal ablation remains investigational. An author-proposed, unvalidated pathway separates PSA/MRI concern from confirmed clinically relevant reclassification and includes transition to watchful waiting when health or life expectancy changes.