Special issue "The advance of solid tumor research in China": 68Ga-PSMA-11 PET/CT for evaluating primary and metastatic lesions in different histological subtypes of renal cell carcinoma

Conventional imaging examinations are not sensitive enough for the early detection of recurrent or metastatic lesions in renal cell carcinoma (RCC) patients. We aimed to explore the role of Ga-68-prostate specific membrane antigen (PSMA)-11 positron emission tomography (PET)/computed tomography (CT) in the detection of primary and metastatic lesions in such patients. We retrospectively analyzed 50 RCC patients who underwent Ga-68-PSMA-11 PET/CT from November 2017 to December 2020. We observed a higher median accuracy and tumor-to-background maximum standard uptake value (SUVmax) ratio (TBR) of Ga-68-PSMA-11 PET/CT in clear cell RCC (ccRCC; 96.57% and 6.00, respectively) than in non-clear cell RCC (ncRCC; 82.05% and 2.99, respectively). The accuracies in detecting lesions in the renal region, bone, lymph nodes and lungs in ccRCC were 100.00%, 95.00%, 98.08% and 75.00%, respectively, and those in the renal region, bone and lymph nodes in ncRCC were 100.00%, 86.67% and 36.36%, respectively. The median TBRs of the lesions from the above locations were 0.38, 10.96, 6.69 and 13.71, respectively, in ccRCC and 0.13, 4.02 and 0.73, respectively, in ncRCC. The PSMA score evaluated with immunohistochemistry was correlated with the SUVmax (P = .046) in RCC. Higher PSMA scores were observed in ccRCC than in ncRCC (P = .031). Ga-68-PSMA-11 PET/CT resulted in changes in clinical management in 12.9% (4/31) of cases because of the discovery of new metastases not detected with conventional imaging. These results indicate that Ga-68-PSMA-11 PET/CT is a promising method for the detection of metastatic lesions in ccRCC, especially for those in the bone and lymph nodes.