Comparisons of mpMRI, 68Ga-PSMA PET/CT and mpMRI combined with 68Ga-PSMA PET/CT in diagnosing prostate cancer based on tumor detection, localization and staging.

ABSTRACT

PURPOSE: To evaluate the diagnostic ability of mpMRI, 68Ga-PSMA PET/CT and mpMRI combined with 68Ga-PSMA PET/CT in detecting and localizing lesions, and further clarify the accuracy of these examinations in tumor staging. METHODS: Seventy patients who underwent mpMRI, 68Ga-PSMA PET/CT and radical prostatectomy were enrolled. The abilities to detect index and clinically significant lesions by three examinations were compared. We further evaluated the ability of these examinations to localize lesions to the superior, inferior, anterior, posterior, left and right halves of the prostate and analyzed their accuracy in local and lymph node staging. RESULTS: There were no significant differences among mpMRI, 68Ga-PSMA PET/CT and mpMRI combined with 68Ga-PSMA PET/CT in their ability to detect index (p = 0.48, p = 0.23 and p = 0.07) and clinically significant lesions (p = 0.30, p = 0.29 and p = 0.06) or to localize lesions in six half divisions of the prostate. With postoperative pathology as reference, both mpMRI (p = 0.10) and mpMRI combined with 68Ga-PSMA PET/CT (p = 0.10) can accurately assess the local staging of prostate cancer. However, 68Ga-PSMA PET/CT underestimates the local staging of prostate cancer (p < 0.01). Regarding lymph node staging, the three types of examination showed no significant differences compared to postoperative pathology (p = 0.63, p = 0.51 and p = 0.14). CONCLUSIONS: With postoperative pathology as reference, 68Ga-PSMA PET/CT underestimates the local tumor staging. MpMRI combined with 68Ga-PSMA PET/CT has no obvious advantages in detecting, localizing or staging prostate cancer compared with mpMRI.