Presentation Authors: Mengxia Chen*, Nanjing, China, People's Republic of, Qing Zhang, Nangjing, China, People's Republic of, Chengwei zhang, Xiaozhi Zhao, Nanjing, China, People's Republic of, Giancarlo Marra, Turin, Italy, Jie Gao, Xiaoyu Lv, Bing Zhang, Yao Fu, Feng Wang, Nanjing, China, People's Republic of, Xuefeng Qiu, Nanjing, Central African Republic, Hongqian Guo, Nanjing, China, People's Republic of
Introduction: Multiparametric magnetic resonance imaging (mpMRI) misses the diagnosis of part of clinically significant prostate cancer (csPCa). 68Ga-labeled PSMA positron emission tomography (68Ga-PSMA PET/CT) has been recently investigated as a first line diagnostic tool. This study was designed to explore whether 68Ga-PSMA PET/CT or the combination of mpMRI and 68Ga-PSMA PET/CT (MRI/PET) can improve the detection of csPCa.
Methods: We retrospectively enrolled 54 patients who underwent both mpMRI and 68Ga-PSMA PET/CT before radical prostatectomy. Regions of interest (ROI) on imaging from mpMRI, 68Ga-PSMA PET/CT and pathology were marked. A lesion was defined when ROI was marked in the same location on continuous imaging at any of the imaging setting. All lesions were recorded by PI-RADS scoring, Mi-ES scoring and pathology results and analyzed. The diagnostic performance was analyzed by receiver operating characteristics (ROC) analysis. Specific improvement for lesions with different PI-RADS score and were analyzed by net reclassification improvement (NRI).
Results: Totally, 90 lesions from 54 patients were analyzed, among which 66 lesions were csPCa. ROC analysis showed improvement of MRI/PET comparing with mpMRI for csPCa detection (Î”AUC 0.06; 95% CI, 0.01â€“0.12; p < 0.05). With calculated cutoff, MRI/PET has a significant overall improvement compared with mpMRI (NRI, 21.9%, p < 0.01), with an improvement on sensitivity (89% versus 76%, p < 0.01) and no sacrifice on specificity (96% versus 88%, p>0.05). Diagnostic improvement for csPCa detection happened on lesions with PI-RADS 3 (NRI 66.7%, P < 0.01).
Conclusions: The combination of 68Ga-PSMA PET/CT and mpMRI improves the detection of csPCa for lesions with PI-RADS 3.
Source of Funding: This study was supported by a grants from the National Natural Science Foundation of China (81772710, 81572519, 81602232), Natural Science Foundation of Jiangsu Province (BK20150112, BK20150097), Nanjing Medical Science and technique Development Foundatio