Single Center Experience with a 4-Week ¹⁷⁷Lu-PSMA-617 Treatment Interval in Patients with Metastatic...

Area of Science:

• Nuclear Medicine
• Oncology
• Radiopharmaceutical Therapy

Background:

• Metastatic castration-resistant prostate cancer (mCRPC) requires effective treatments.
• 177Lu-PSMA-617 offers a promising theragnostic approach for mCRPC.
• Optimal dosing, intervals, and patient selection for 177Lu-PSMA-617 remain unclear.

Purpose of the Study:

• To evaluate the safety and efficacy of 177Lu-PSMA-617 in mCRPC patients.
• To determine the optimal treatment interval and identify predictors of response.
• To assess the association between pre-treatment PSMA PET/CT parameters and treatment outcomes.

Main Methods:

• Retrospective analysis of 62 mCRPC patients treated with 177Lu-PSMA-617.
• Treatment administered in cycles at four-week intervals.
• Evaluation of progression-free survival (PFS), overall survival (OS), and prostate-specific antigen (PSA) response.

Main Results:

• A median of three treatment cycles were administered.
• Progression-free survival was 4.9 months and overall survival was 17.2 months.
• 58.7% of patients achieved a significant PSA response (>50%), associated with longer OS.
• No major adverse events were reported.
• Pre-treatment PSMA PET/CT parameters did not predict treatment response.

Conclusions:

• 177Lu-PSMA-617 therapy at four-week intervals is safe and effective for mCRPC.
• Significant PSA response is a key indicator of improved overall survival.
• Current PSMA PET/CT-derived parameters are insufficient for selecting patients who will respond to treatment; novel biomarkers are necessary.