Evaluating the Correlation Between Serum PSA Values and Gleason Score of Prostate Carcinoma with Ga۶۸-PSMA Uptake in Prostate Tumor in Primary Staging

Introduction: Ga۶۸-PSMA PET/CT plays a crucial role in staging, evaluating treatment, and diagnosing local recurrence of prostate tumors. Recently, the NCCN guidelines have recommended it as the preferred staging method for unfavorable intermediate and high-risk patients. This study aims to evaluate the correlation between serum PSA levels and Gleason score of prostate tumors with the findings of Ga۶۸-PSMA PET/CT scans in primary staging.Methods: In this cross-sectional study, patients with newly diagnosed prostate cancer referred for Ga۶۸-PSMA PET/CT whole-body scans were enrolled. The scans were performed at three time points (early, whole-body, and late). The standardized uptake value of Ga۶۸-PSMA in the primary tumor and its association with serum PSA levels, tumor Gleason score, and presence of tumor metastasis were evaluated and analyzed. A p-value<۰.۰۵ was considered statistically significant in all statistical analyses.Results: A total of ۴۹ male patients with a median age of ۶۵ years (Interquartile range: ۵۹-۶۹) were included in the study. Of these patients, ۴۳.۹% were classified as high-risk based on their Gleason score. The median serum PSA level was ۱۷ ng/mL (Interquartile range: ۸.۰۲-۴۲.۱۰). PSA levels correlated with the SUVmax of the tumor in the whole-body stage of the scan (P-value<۰.۰۵; r=+۰.۳۹۲), but not in the early or late stages (P-value>۰.۰۵). Gleason scores showed a positive correlation with tumor SUVmax in all three scan stages (P-value<۰.۰۵).Conclusion: Our results indicate that the Gleason score significantly correlates with the SUVmax of the prostate tumor in all three time points of the scan. However, serum PSA levels only correlate with the tumor SUVmax in the whole-body stage of the scan, not in the early and late stages. In the whole-body stage, a higher SUVmax is significantly associated with higher Gleason scores ,bladder wall and seminal vesicle invasion, and lymph node metastasis (P-value<۰.۰۵ in all cases).

Keywords:

Prostate Cancer , tumor staging , Ga۶۸-PSMA PET/CT scan