Xin Gao,1,* Yijun Fu,1,* Zimei Mo,1 Yongtong Ruan2 

1Department of Urology, Yangjiang Hospital of Traditional Chinese Medicine, Affiliated to Guangzhou University of Chinese Medicine, Yangjiang, Guangdong, People’s Republic of China; 2Department of Urology, Yangjiang Hospital of Traditional Chinese Medicine, Yangjiang, Guangdong, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Yongtong Ruan, Department of Urology, Yangjiang Hospital of Traditional Chinese Medicine, Shiwan North Road, Jiangcheng District, Yangjiang, 529500, People’s Republic of China, Tel +86-13432578081, Email ruanyongtong@qq.com

Background: Prostate cancer remains a significant global health burden, with biochemical recurrence (BCR) affecting 20– 50% of patients post-radical prostatectomy. This study aimed to investigate the relationship between preoperative PSA levels and BCR-free survival in Asian populations.
Methods: We conducted a retrospective cohort study of 3,092 prostate cancer patients who underwent radical prostatectomy at Yonsei University College of Medicine, Korea (1992– 2014). The exposure variable was preoperative PSA level, and the primary outcome was BCR-free survival. Covariates included age, Gleason score, pathological stage, surgical margins, and other clinical factors. Patients were followed quarterly for two years post-surgery, semi-annually for three years, then annually thereafter (median follow-up: 66 months).
Results: Using piecewise linear regression, we identified a significant threshold effect at PSA 5.1 ng/mL. Above this threshold, each unit increase in LnPSA was associated with a 6.10-month reduction in BCR-free survival (95% CI: − 7.64 to − 4.56, P< 0.0001). Higher PSA levels correlated with increased adverse pathological features and shorter BCR-free survival across all risk groups.
Conclusion: This study establishes a critical PSA threshold of 5.1 ng/mL for BCR risk stratification in Asian populations. Above this threshold, each unit increase in LnPSA correlates with a 6.10-month reduction in BCR-free survival, providing valuable guidance for post-operative monitoring and personalized treatment strategies.

Keywords: prostate cancer, prostate-specific antigen, PSA, biochemical recurrence, nonlinearity