Therapeutic Outcomes of (177)Lu-PSMA Targeted Therapy in Patients with Metastatic Castration-Resistant Prostate Cancer: A Single-Center Study

OBJECTIVE(S): This study aimed to evaluate the therapeutic outcomes of (177)Lutetium ((177)Lu)-PSMA-617 in metastatic castrate-resistant prostate cancer (mCRPC) patients, based on post-treatment imaging findings. METHODS: All post-therapeutic scans were collected retrospectively from patients treated with 100-200 mCi (177)Lu-PSMA-617 from March 2018 to December 2020 for mCRPC. Two independent readers interpreted the scans and visually categorized them into three strata: responsive, stable, and progressive. The responses were defined based on changes in the number of detected lesions, as well as the intensity of the hottest lesion. Data were registered, and the trend of changes was descriptively discussed. RESULTS: Out of 36 patients (aged 67±8.8 years), 23 underwent at least two treatment cycles. Nineteen patients (82.6%) had bone metastases, 12 (52.2%) had nodal metastases, 5 (21.7%) had liver metastases, and 3 (13.0%) had lung metastases. Eleven patients (47.8%) were considered responsive in the post-therapeutic scans, two of which experienced complete eradication of the metastatic sites. Three patients (13%) were categorized as progressive, and 9 (39.1%) patients remained stable. Regarding mortality, nine patients died during the late follow-up (median of 24 months). In the surviving population, 65% reported no or mild pain in the final follow-up, based on a 5-point scale pain assessment. CONCLUSION: The treatment of mCRPC patients with (177)Lu-PSMA-617 may limit their disease progression and preserve their physical performance, which are important factors in their survival and quality of life.