Lutetium-177-PSMA-617 in Low-Volume Hormone-Sensitive Metastatic Prostate Cancer: A Prospective Pilot Study

• Published in: Clinical cancer research Vol. 27; no. 13; pp. 3595 - 3601
• Main Authors: Privé, Bastiaan M, Peters, Steffie M B, Muselaers, Constantijn H J, van Oort, Inge M, Janssen, Marcel J R, Sedelaar, J P Michiel, Konijnenberg, Mark W, Zámecnik, Patrik, Uijen, Maike J M, Schilham, Melline G M, Eek, Annemarie, Scheenen, Tom W J, Verzijlbergen, J Fred, Gerritsen, Winald R, Mehra, Niven, Kerkmeijer, Linda G W, Smeenk, Robert J, Somford, Diederik M, van Basten, Jean-Paul A, Heskamp, Sandra, Barentsz, Jelle O, Gotthardt, Martin, Witjes, J Alfred, Nagarajah, James
• Format: Journal Article
• Language: English
• Published: United States 01.07.2021
• Subjects: Androgen Antagonists - therapeutic use; Dipeptides - adverse effects; Heterocyclic Compounds, 1-Ring - adverse effects; Hormones - therapeutic use; Humans; Male; Pilot Projects; Prospective Studies; Prostate-Specific Antigen; Prostatic Neoplasms, Castration-Resistant - drug therapy; Prostatic Neoplasms, Castration-Resistant - metabolism; Prostatic Neoplasms, Castration-Resistant - radiotherapy; Quality of Life; Radioisotopes; Radiopharmaceuticals
• ISSN: 1078-0432; 1557-3265
• DOI: 10.1158/1078-0432.CCR-20-4298

[ Lu]Lu-PSMA-617 radioligand therapy ( Lu-PSMA) is a novel treatment for metastatic castration-resistant prostate cancer (mCRPC), which could also be applied to patients with metastatic hormone-sensitive prostate cancer (mHSPC) with PSMA expression. In this prospective study (NCT03828838), we analyzed toxicity, radiation doses, and treatment effect of Lu-PSMA in pateints with low-volume mHSPC. Ten progressive patients with mHSPC following local treatment, with a maximum of ten metastatic lesions on [ Ga]Ga-PSMA-11 PET/diagnostic-CT imaging (PSMA-PET) and serum PSA doubling time <6 months received two cycles of Lu-PSMA. Whole-body single-photon emission CT/CT (SPECT/CT) and blood dosimetry was performed to calculate doses to the tumors and organs at risk (OAR). Adverse events (AE), laboratory values (monitoring response and toxicity), and quality of life were monitored until week 24 after cycle 2, the end of study (EOS). All patients underwent PSMA-PET at screening, 8 weeks after cycle 1, 12 weeks after cycle 2, and at EOS. All patients received two cycles of Lu-PSMA without complications. No treatment-related grade III-IV adverse events were observed. According to dosimetry, none of the OAR reached threshold doses for radiation-related toxicity. Moreover, all target lesions received a higher radiation dose than the OAR. All 10 patients showed altered PSA kinetics, postponed androgen deprivation therapy, and maintained good quality of life. Half of the patients showed a PSA response of more than 50%. One patient had a complete response on PSMA-PET imaging until EOS and two others had only minimal residual disease. Lu-PSMA appeared to be a feasible and safe treatment modality in patients with low-volume mHSPC.