Presentation Authors: Chengwei Zhang*, Xiaozhi Zhao, Feng Wang, Hongqian Guo, Nanjing, China, People's Republic of
Introduction: Since the prostate-specific membrane antigen (PSMA) is highly expressed in the cell surface of the solid tumor microvasculature including renal cell carcinoma (RCC), our purpose was to clarify the clinical value of 68Ga-PSMA PET/CT imaging in the diagnosis for RCC.
Methods: All together 118 patients with RCC were involved in the study. 68Ga-PSMA PET/CT was performed to detect both primary renal lesions or metastasis. Additionally, 68Ga-PSMA PET/CT was performed every 3 month on 12 patients with metastasis undergoing target therapy to evaluate the treatment effect of target therapy. SUVmax was calculated for all the PET-positive interested lesions.
Results: After analysis for primary lesions, clear cell RCC (ccRCC) presented higher PSMA uptake than other pathologic type (papillary, chromophobe, et al) (SUVmax: 17.30Â±5.15 vs 5.72Â±3.02, P < 0.001, Fig.1A). No differences were found among the groups of different WHO/ISUP Grade. 68Ga-PSMA PET/CT image showed intense uptake in bone (SUVmax: 20.59Â±10.82, Fig.1B) and lymph node (SUVmax: 14.27Â±12.41, Fig.1A) metastatic lesions. Small lung metastases were PET-negative (SUVmax: 3.51Â±2.75). Among the 12 patients undergoing target therapy, 8 patients were treated with pazopanib and 4 with sorafenib. Although they remained Stable Disease (SD) on RECIST 1.1, SUVmax on PSMA PET/CT of the lesions reduced obviously to access the treamtent effect of target therapy. (Fig.2)_x000D_
Fig.1 68Ga-PSMA PET/CT presented intense uptake on primary lesions (A, bilateral kidney cancer), lymph node (A) and bone (B) metastasis. _x000D_
Fig.2 The value of SUVmax reduced obviously presented the treatment effect of target therapy on lymph node metastasis (A) and primary kidney lesions (B).
Conclusions: 68Ga-PSMA PET/CT presented great diagnostic value for ccRCC diagnosis. 68Ga-PSMA PET/CT also presented the value of evaluate the therapeutic effect of first-line target therapy for advanced ccRCC.