Lutetium-177(177Lu)-PSMA-617 improves survival for patients with metastatic castration-resistant prostate cancer (mCRPC), but outcomes are heterogeneous and standardized risk stratification tools are lacking. We developed a novel risk stratification tool for patients treated with 177Lu-PSMA-617.
We conducted a retrospective analysis of 163 patients at Emory Winship Cancer Institute. Four prognostic models using Cox proportional hazards models were constructed using best-subset variable selection and integrated into a composite model.
Among 163 patients (52% White, 44% Black; 80% previous taxane use) body mass index (BMI) decline during treatment was associated with shorter progression-free survival (PFS) and overall survival (OS) (HR = 1.75, p = 0.03; HR = 2.35, p = 0.031). Higher subcutaneous adipose tissue index (SATI)/skeletal muscle index (SMI) was independently associated with improved OS (HR = 0.5, p = 0.019), whereas higher visceral adipose tissue index (VATI)/SATI was independently associated with worse OS (HR = 2.62, p = 0.005). A body composition-based prognostic score identified VATI/SATI, SMI, and total adiposity as the strongest OS predictors (C = 0.629). The composite score incorporating inflammatory biomarkers and body composition demonstrated good discrimination (C-index = 0.732) and effectively stratified patients by PFS and OS. For PFS, relative risks across increasing risk quartiles were 0.34, 0.40, and 0.62 in comparison to the highest risk quartile (p = 0.034). For OS, corresponding hazard ratios were 0.15, 0.19, and 0.54 (p = 0.003).
A risk score incorporating body composition and inflammatory biomarkers demonstrates prognostic value for patients treated with 177Lu-PSMA-617.
The oncologist. 2026 Jul 11 [Epub ahead of print]
Margo B Gerke, Angelo Marra, Michelle Jayaraj, Ahmet Yildrim, Akshay Bedmutha, Jacqueline T Brown, Bassel Nazha, Jacob E Berchuck, Ravi Bharat Parikh, Shahid Ahmed, Jordan Alana Ciuro, Caitlin Hartman, Greta Russler McClintock, Sarah Caulfield, Omer Kucuk, Bradley Curtis Carthon, David M Schuster, Saima Muzahir, Yuan Liu, Mehmet Asim Bilen
Emory University School of Medicine, Atlanta, GA 30322, USA., Biostatistics Shared Resource, Winship Cancer Institute, Emory University, Atlanta, GA 30322, USA., Department of Radiology and Imaging Sciences, Division of Nuclear Medicine and Molecular Imaging, Emory University, Atlanta, GA 30322, USA., Department of Hematology and Medical Oncology, Emory University School of Medicine, Atlanta, GA, 30322, USA., Winship Cancer Institute of Emory University, Atlanta, GA 30322, USA., Department of Biostatistics and Bioinformatics, Emory University, Atlanta, GA 30322, USA.