Comparison of multiparametric prostate MR imaging and Ga-68 PSMA PET-CT imaging in prostate cancer staging

Background/Aim: Staging in prostate cancer is essential for determining the right treatment approach and its execution. This study assessed the staging effectiveness of multiparametric prostate magnetic resonance imaging (MpMRI) compared to prostate-specific membrane antigen (PSMA) positron emission tomography – computed tomography (PET-CT) and examined the preoperative information that they provide. Methods: We collected data from patients diagnosed with prostate cancer who visited our clinic between June 2020 and November 2022. The results from MpMRI performed prior to biopsy were compared to those from PSMA PET-CT conducted after diagnosis, alongside the outcomes of pathological evaluations. Results: There was no significant correlation between MpMRI and PSMA PET-CT findings and the final pathology results regarding extraprostatic extension. However, both imaging techniques showed a significant correlation with the final pathology in evaluating pelvic lymph-node metastasis and seminal vesicle invasion. In terms of lesion localization, no significant correlation was found between the final site of the pathological lesion and MpMRI, while a significant correlation was noted with PSMA PET-CT. Patients with positive surgical margins had significantly elevated serum PSA levels, size of the index lesion identified in MpMRI, and maximum standardized uptake values (SUV max) of PSMA. Conclusion: Although both imaging methods offer important staging insights, further research is needed to clarify their respective limitations and benefits. In the future, these techniques may have additional roles in predicting surgical margin positivity before surgery.