Impact of an Early Prostate-Specific Antigen Response on Biochemical Progression during Upfront Androgen Receptor Signal Inhibitor Therapy for Metastatic Hormone-Sensitive Prostate Cancer

Urol Int. 2026;110(1):62-68. doi: 10.1159/000546327. Epub 2025 May 22.

Abstract

Introduction: We examined the impact of prostate-specific antigen (PSA) response, which is associated with survival, on patients with metastatic hormone-sensitive prostate cancer (mHSPC) treated with androgen receptor signal inhibitors (ARSIs).

Methods: We retrospectively reviewed 82 patients with mHSPC who received upfront ARSI treatment. The primary endpoint was PSA progression-free survival (PFS). Patients whose PSA levels decreased to ≤0.2 ng/mL at 3 months after ARSI initiation were classified as deep early, those with >0.2-≤1.0 ng/mL as early, and others as non-PSA responders.

Results: The median age of patients was 73 years old, and the median baseline PSA value was 361 ng/mL. Among 82 patients, 32 (39%), 16 (20%), and 34 (41%) were categorized into deep early, early, and non-early PSA responders, respectively. There was a significant association between PSA response status, hemoglobin, and PSA value. During follow-up (median, 23.0 months), 31 (37.8%) patients experienced PSA progression. The PSA progression rates of the deep early, early, and non-early PSA responders were 15.6%, 31.2%, and 61.8% (p < 0.001), and their 2-year PSA PFS rates were 90.5%, 70.7%, and 38.9%, respectively.

Conclusion: An early PSA response within 3 months of ARSI initiation was associated with PSA progression in patients with mHSPC.

Keywords: Androgen receptor; Prostate cancer; Prostate-specific antigen.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Androgen Receptor Antagonists* / therapeutic use
  • Disease Progression
  • Humans
  • Male
  • Middle Aged
  • Neoplasm Metastasis
  • Progression-Free Survival
  • Prostate-Specific Antigen* / blood
  • Prostatic Neoplasms* / blood
  • Prostatic Neoplasms* / drug therapy
  • Prostatic Neoplasms* / pathology
  • Receptors, Androgen
  • Retrospective Studies
  • Time Factors
  • Treatment Outcome

Substances

  • Prostate-Specific Antigen
  • Androgen Receptor Antagonists
  • Receptors, Androgen