Conventional imaging lacks accuracy for primary characterization and metastatic staging of clear cell renal cell carcinoma (ccRCC). This study evaluated [68Ga]Ga-DPI-4452 PET/CT for ccRCC identification and staging, and directly compared its efficacy with [18F]FDG.
Patients were prospectively recruited into two cohorts. Cohort A (n=30, suspected renal masses scheduled for surgery or biopsy) evaluated the initial diagnostic and staging performance. Cohort B (n=30, suspected/confirmed metastatic ccRCC) underwent paired [68Ga]Ga-DPI-4452 and [18F]FDG PET/CT within 14 days to assess comparative staging efficacy. Reference standards included histopathology and/or composite clinicoradiological follow-up (≥3 months).
A total of 60 patients (38 men, 22 women; overall median age, 58 years) were enrolled. In Cohort A (23 ccRCC, 7 non-ccRCC/benign), [68Ga]Ga-DPI-4452 PET/CT identified primary ccRCC with 100% sensitivity and 85.7% specificity (AUC for SUVmax: 0.913). For systemic staging, [68Ga]Ga-DPI-4452 PET/CT detected 42 metastatic lesions versus 23 on CT/MRI, identifying 19 additional lesions (an 82.6% increase). Tracer uptake correlated strongly with tissue CAIX H-score (r = 0.84, P < 0.001). In the initial analysis of Cohort B, [68Ga]Ga-DPI-4452 significantly outperformed [18F]FDG by successfully detecting numerous FDG-negative metastases, and it exhibited markedly higher uptake in ccRCC lesions (median SUVmax: 35.4 vs. 8.2 for FDG, P<0.01). Importantly, [68Ga]Ga-DPI-4452 PET findings identified previously unknown metastatic regions in 40% of patients and directly altered clinical management in 16.7% (5/30) (e.g., shifting to active surveillance or enabling curative-intent surgery). No tracer-related adverse events occurred across either cohort.
[68Ga]Ga-DPI-4452 PET/CT is a safe and highly effective imaging tool for ccRCC. By successfully characterizing primary renal masses and demonstrating preliminary superiority over CT/MRI and [18F]FDG in detecting hidden metastatic burdens, it refines systemic clinical staging and directly empowers oncologists to optimize personalized treatment decisions.
ChiCTR2600121783.
Chinese PLA General Hospital.
Has not received any funding.
All authors have declared no conflicts of interest.