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Updated: Apr 8, 2026
A Bioluminescent and Fluorescent Orthotopic Syngeneic Murine Model of Androgen-dependent and Castration-resistant Prostate Cancer
Published on: March 6, 2018
Very deep prostate-specific antigen decline is associated with longer rPFS in patients with metastatic
Caner Kapar1, Ilkay Gulturk2, Volkan Tugcu3
1Department of Medical Oncology, Bakirkoy Dr. Sadi Konuk Training and Research Hospital, Dr Tevfik Sağlam Cd., No:11 Zuhuratbaba, Istanbul 34147, Turkey.
Background:
Prostate-specific antigen (PSA) is widely used in the diagnosis and monitoring of prostate cancer. The prognostic relevance of very low PSA levels has not been clearly established in metastatic castration-sensitive prostate cancer (mCSPC). More sensitive PSA assays may provide more accurate estimates of clinical outcomes.
Objectives:
To evaluate the relationship between achieving very deep PSA levels (⩽0.02 ng/mL) within 6 months of treatment and radiologic progression-free survival (rPFS) in patients with mCSPC.
Design:
A retrospective, unicenter observational study conducted at a tertiary oncology center.
Methods:
A total of 203 patients with mCSPC who received first-line treatment with luteinizing hormone-releasing hormone analogs, androgen receptor pathway inhibitors, or docetaxel were included. Patients were stratified into four groups based on their PSA nadir levels: ⩽0.02, 0.02-0.2, 0.2-4, and >4 ng/mL. Kaplan-Meier and Cox regression analyses were used to assess the association between PSA nadir and rPFS.
Results:
Patients achieving PSA ⩽ 0.02 ng/mL had significantly longer rPFS (median: 59.2 months) compared to other PSA groups. Multivariable analysis confirmed PSA ⩽ 0.02 ng/mL as an independent predictor of rPFS (HR: 2.02, p < 0.001). The overall log-rank p-value for group comparison was < 0.001.
Conclusion:
A very deep PSA response (⩽0.02 ng/mL) is associated with longer rPFS and may serve as a prognostic marker in mCSPC. This threshold could be considered in future clinical trial design and treatment stratification.
