Stereotactic radiotherapy in oligometastatic prostate cancer: a single-center experience.

INTRODUCTION

Oligometastatic prostate cancer represents an intermediate disease state potentially amenable to metastasis-directed therapies such as stereotactic body radiotherapy (SBRT), aiming to delay disease progression and postpone systemic treatment.

AIM: The aim of this study was to evaluate the real-world outcomes of SBRT in patients with hormone-sensitive oligometastatic prostate cancer.

METHODS

This single-center retrospective study included patients with hormone-sensitive oligometastatic prostate cancer staged with PSMA PET and treated with SBRT at a tertiary center between January 2022 and March 2024. The primary endpoint was hormone therapy-free survival (HTFS). Secondary endpoints included event-free survival (EFS), local control, overall survival (OS), and toxicity.

RESULTS

A total of 34 patients were included, predominantly with low-volume disease (79.4% with a single metastasis). SBRT achieved significant biochemical responses (PSA50 in 69.7%; median PSA nadir 0.19 ng/mL). HTFS rates were 85.2% and 74.6% at 12 and 24 months, respectively, with the median not reached. Median EFS was 16.2 months. Local control was 84.2%, and 24-month OS was 87.8%. Toxicity was minimal, with no grade ≥ 3 adverse events. A PSA nadir ≤ 0.20 ng/mL and ISUP ≤ 2 were associated with improved outcomes.

CONCLUSIONS

SBRT may delay systemic therapy without compromising disease control in oligometastatic prostate cancer. Its integration into personalized treatment strategies, guided by biological and biochemical factors, represents a promising therapeutic approach.