Impact of Immunohistochemical Biomarkers on Predicting the Risk of Biochemical Recurrence for Patients that Underwent Radical Prostatectomy: A Literature Review.

Background: Prostate cancer (PCa) remains a significant global health issue, exhibiting a spectrum of clinical behaviours from indolent to aggressive. Biomarkers are crucial for risk assessment, treatment selection and prognosis prediction. Despite their importance, accurately evaluating PCa aggressiveness and guiding personalised treatment strategies present challenges. This review aims to evaluate biomarkers for assessing recurrence risk following radical prostatectomy, with a focus on personalised follow-up and timely intervention for high-risk patients. This review assesses the clinical significance of immunohistochemical biomarkers, including LIM domain kinase 1 (LIMK1), Antigen Kiel 67 (Ki67), PTEN and ERG, in PCa management. A comprehensive literature review examined the correlation between these biomarkers and biochemical recurrence (BCR) in patients undergoing radical prostatectomy. Our search included articles published between 2019 and 2024, yielding 87 articles, with 7 focused on the correlation between LIMK1 and BCR, 46 on Ki67 and 34 on PTEN/ERG biomarkers. After applying the exclusion criteria, 36 articles were included for review. LIMK1, a serine/threonine kinase, is highly expressed in cancers like PCa. It influences cell survival and motility through actin cytoskeleton reorganisation, correlating with poor prognosis, aggressive tumour behaviour and BCR. Similarly, Ki67, a marker of cell proliferation, predicts high-risk PCa and worse prognosis, particularly in castration-resistant cases, although its association with recurrence risk remains debated. PTEN loss and ERG fusion are prevalent genetic alterations in PCa, with PTEN loss linked to poor prognosis and ERG fusion associated with increased disease progression and BCR post-prostatectomy. Integrating these biomarkers into clinical practice can enhance risk stratification and inform personalised treatment strategies for patients with PCa. Despite promising findings, further validation studies and standardisation of detection methods are needed to ensure the clinical utility of these biomarkers. Continued research is essential to validate and optimise the clinical utility of these biomarkers, paving the way for more effective PCa management strategies and improved patient outcomes and quality of life.