Mehmet Oğuz Kartal,Ayşenur Sinem Kartal,Nazım Coşkun,Mehmet Ali Nahit Şendur,Elif Özdemir
{"title":"Bone matters: Ga-68 PSMA PET/CT volumetrics predict PSA-PFS and OS in bone-dominant mCRPC patients treated with [¹⁷⁷Lu]Lu-PSMA-617.","authors":"Mehmet Oğuz Kartal,Ayşenur Sinem Kartal,Nazım Coşkun,Mehmet Ali Nahit Şendur,Elif Özdemir","doi":"10.1007/s00259-025-07556-w","DOIUrl":null,"url":null,"abstract":"INTRODUCTION\r\nThis study aimed to evaluate the prognostic value of baseline, interim, and change-based (Δ) volumetric parameters derived from PSMA PET/CT imaging in predicting PSA progression-free survival (PSA-PFS) and overall survival (OS) in bone-dominant metastatic castration-resistant prostate cancer (mCRPC) patients treated with [¹⁷⁷Lu]Lu-PSMA-617.\r\n\r\nMETHODS\r\nThis retrospective study included 56 bone-dominant mCRPC patients who underwent [⁶⁸Ga]Ga-PSMA PET/CT imaging before and after two cycles of [¹⁷⁷Lu]Lu-PSMA therapy. Quantitative parameters, including SUVmean, PSMA tumor volume (PSMA-TV), and total lesion PSMA activity (TL-PSMA), were extracted using a fixed threshold of SUV ≥ 3. Δ values were calculated as the relative change between baseline and interim scans. Associations with PSA-PFS and OS were analyzed using Cox regression and Kaplan-Meier survival analyses.\r\n\r\nRESULTS\r\nThe presence of new lesions on interim PSMA PET/CT and a reduction of PSMA-TV(Bone) ≤ 10.7% were identified as independent predictors of shorter PSA-PFS (p = 0.022 and p = 0.043, respectively). For OS, an interim PSMA-TV(Bone) > 310.3 mL remained an independent prognostic factor both in the entire cohort (p < 0.001) and in the subgroup without early PSA progression (p = 0.002). While baseline SUVmean values were associated with PSA-PFS, no significant association with OS was observed.\r\n\r\nCONCLUSION\r\nIn bone-dominant mCRPC patients treated with [¹⁷⁷Lu]Lu-PSMA, ΔPSMA-TV(Bone) ≤ 10.7% and the presence of new lesions were independent predictors of PSA-PFS, while interim bone tumor volume was significantly associated with OS. These findings highlight the clinical relevance of bone-specific volumetric parameters, which may serve as a potential alternative to whole-body tumor assessments by providing more practical and targeted prognostic insights in this patient population.","PeriodicalId":11909,"journal":{"name":"European Journal of Nuclear Medicine and Molecular Imaging","volume":"74 1","pages":""},"PeriodicalIF":7.6000,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"European Journal of Nuclear Medicine and Molecular Imaging","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1007/s00259-025-07556-w","RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING","Score":null,"Total":0}
引用次数: 0
Abstract
INTRODUCTION
This study aimed to evaluate the prognostic value of baseline, interim, and change-based (Δ) volumetric parameters derived from PSMA PET/CT imaging in predicting PSA progression-free survival (PSA-PFS) and overall survival (OS) in bone-dominant metastatic castration-resistant prostate cancer (mCRPC) patients treated with [¹⁷⁷Lu]Lu-PSMA-617.
METHODS
This retrospective study included 56 bone-dominant mCRPC patients who underwent [⁶⁸Ga]Ga-PSMA PET/CT imaging before and after two cycles of [¹⁷⁷Lu]Lu-PSMA therapy. Quantitative parameters, including SUVmean, PSMA tumor volume (PSMA-TV), and total lesion PSMA activity (TL-PSMA), were extracted using a fixed threshold of SUV ≥ 3. Δ values were calculated as the relative change between baseline and interim scans. Associations with PSA-PFS and OS were analyzed using Cox regression and Kaplan-Meier survival analyses.
RESULTS
The presence of new lesions on interim PSMA PET/CT and a reduction of PSMA-TV(Bone) ≤ 10.7% were identified as independent predictors of shorter PSA-PFS (p = 0.022 and p = 0.043, respectively). For OS, an interim PSMA-TV(Bone) > 310.3 mL remained an independent prognostic factor both in the entire cohort (p < 0.001) and in the subgroup without early PSA progression (p = 0.002). While baseline SUVmean values were associated with PSA-PFS, no significant association with OS was observed.
CONCLUSION
In bone-dominant mCRPC patients treated with [¹⁷⁷Lu]Lu-PSMA, ΔPSMA-TV(Bone) ≤ 10.7% and the presence of new lesions were independent predictors of PSA-PFS, while interim bone tumor volume was significantly associated with OS. These findings highlight the clinical relevance of bone-specific volumetric parameters, which may serve as a potential alternative to whole-body tumor assessments by providing more practical and targeted prognostic insights in this patient population.
期刊介绍:
The European Journal of Nuclear Medicine and Molecular Imaging serves as a platform for the exchange of clinical and scientific information within nuclear medicine and related professions. It welcomes international submissions from professionals involved in the functional, metabolic, and molecular investigation of diseases. The journal's coverage spans physics, dosimetry, radiation biology, radiochemistry, and pharmacy, providing high-quality peer review by experts in the field. Known for highly cited and downloaded articles, it ensures global visibility for research work and is part of the EJNMMI journal family.