PSMA PET/CT and Multiparametric MRI in Assessing Local Extension and Lymph Node Metastasis in Prostate Cancer

Area of Science:

• Oncology
• Radiology
• Nuclear Medicine

Background:

• Accurate staging of prostate cancer (PCa) is crucial for treatment planning.
• Seminal vesicle invasion (SVI), extraprostatic extension (EPE), and lymph node (LN) metastasis are key pathological indicators influencing treatment decisions.
• Evaluating the diagnostic performance of advanced imaging techniques is essential for improving PCa staging.

Purpose of the Study:

• To compare the diagnostic performance of PSMA PET/CT and mpMRI in detecting SVI, EPE, and LN metastasis in PCa patients.
• To assess the utility of prostate-specific antigen (PSA) and maximum standardized uptake value (SUVmax) in predicting these pathological outcomes.
• To correlate imaging findings with histopathological results following radical prostatectomy.

Main Methods:

• Retrospective analysis of 66 PCa patients who underwent preoperative PSMA PET/CT and radical prostatectomy.
• Comparison of imaging findings from PSMA PET/CT and mpMRI (available in 33 patients) with histopathology.
• Calculation of sensitivity, specificity, and accuracy for detecting SVI, EPE, and LN metastasis.
• Evaluation of the relationship between PSA, SUVmax, and pathological outcomes.

Main Results:

• PSMA PET/CT exhibited higher sensitivity and overall accuracy than mpMRI for SVI detection, while mpMRI showed higher specificity.
• For EPE, PSMA PET/CT was more sensitive, and mpMRI was more specific; predictive values were similar.
• SUVmax and PSA showed a positive correlation but did not significantly differentiate patients based on SVI, EPE, or LN metastasis.
• LN uptake on PSMA PET/CT generally agreed with pathology, but without significant association with SUVmax or PSA.

Conclusions:

• PSMA PET/CT is more effective for detecting SVI, whereas mpMRI is more prominent for EPE.
• SUVmax shows near-significant potential for SVI and LN metastasis detection.
• PSA levels are not valuable for diagnosing local prostate invasion or LN metastases.