Clinical Outcomes of Metastasis-directed Therapy for Oligo-metastatic Prostate Cancer Diagnosed Using PSMA-PET/CT or Whole-body MRI

Anticancer Res. 2025 Jun;45(6):2515-2525. doi: 10.21873/anticanres.17623.

Abstract

Background/aim: Data on clinical outcomes in Japanese patients following metastasis-directed therapy (MDT) for oligo-metastatic prostate cancer (PCa) diagnosed using next-generation imaging modalities [prostate-specific membrane antigen-targeted positron emission tomography/computed tomography (PSMA-PET/CT) or whole-body diffusion-weighted magnetic-resonance imaging (WB-MRI)] are limited.

Patients and methods: We retrospectively evaluated clinical outcomes in patients with oligo-metastatic PCa diagnosed using PSMA-PET/CT or WB-MRI and subsequently treated with MDT between February 2018 and June 2023 at our institution.

Results: In total, 26 patients were analyzed: 14 with hormone-sensitive PCa (oligo-recurrence) and 12 with castration-resistant PCa (oligo-progression). The median patient age was 74 years at the time of diagnosing oligo-metastasis. A total of 30 sites were irradiated. The median prescribed dose was 62.4 Gy in 31 fractions for sites treated with conventional fractionated or moderately hypo-fractionated external-beam radiation therapy (EBRT), and 35 Gy in five fractions for those treated with stereotactic body radiation therapy (SBRT). Systemic therapies were administered in 88.5%. The median follow-up period after the diagnosis of oligo-metastasis was 34.2 months. The overall survival, biochemical failure-free survival, and clinical failure-free survival rates were 94.1, 48.7, and 55.4% at three years, respectively. The local control rate of MDT sites was 96.7%. Grade 2 MDT-related toxicities were observed in 7.6%, whereas no ≥ grade 3 toxicities were reported.

Conclusion: MDT for oligo-metastatic PCa diagnosed using next-generation imaging modalities in a Japanese population can result in favorable disease-free and survival outcomes with acceptable morbidities.

Keywords: PSMA-PET/CT; Prostate cancer; metastasis-directed therapy; oligo-metastasis; whole-body diffusion-weighted MRI.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Antigens, Surface
  • Glutamate Carboxypeptidase II / metabolism
  • Humans
  • Magnetic Resonance Imaging* / methods
  • Male
  • Middle Aged
  • Neoplasm Metastasis
  • Positron Emission Tomography Computed Tomography* / methods
  • Prostatic Neoplasms* / diagnostic imaging
  • Prostatic Neoplasms* / pathology
  • Prostatic Neoplasms* / therapy
  • Prostatic Neoplasms, Castration-Resistant* / diagnostic imaging
  • Prostatic Neoplasms, Castration-Resistant* / pathology
  • Radiosurgery
  • Retrospective Studies
  • Treatment Outcome
  • Whole Body Imaging* / methods

Substances

  • Glutamate Carboxypeptidase II
  • FOLH1 protein, human
  • Antigens, Surface