The role of [18F]PSMA-1007 PET/CT in staging of prostate cancer: Influence of bone uptake and relationship with D'Amico risk classification.

BACKGROUND

Prostate cancer represents a significant global health challenge, particularly in Mexico where it ranks as the leading cause of cancer-related mortality among men. The introduction of Prostate-Specific Membrane Antigen labeled with fluoride [18F]F-PSMA-1007 PET/CT has revolutionized diagnostics, enabling identification of metastases not visible on conventional imaging, although it presents unspecific bone uptake (UBU) in up to 72% of patients.

METHODS

Eighty-one patients with newly diagnosed prostate cancer who underwent [18F]F-PSMA-1007 PET/CT for staging were retrospectively analyzed. Patients were categorized according to D'Amico risk classification. The prevalence of PSMA-positive lesions in various anatomical sites was assessed, defining unspecific bone uptake as focal uptake without meeting PROMISE criteria for osseous metastases.

RESULTS

Metastatic disease, specifically defined by the presence of miN1 and/or miM1a-c lesions, was detected in a substantial majority of the patients, totaling 61 individuals, which corresponds to 75% of the entire cohort. Abnormal bone uptake was identified in 58% of cases, distributed equally across D'Amico risk groups. No significant association was found between bone uptake frequency and antigen prostatic specific (PSA) levels or Gleason score (p = 0.24). However, SUVmax was independently associated with metastasis (adjusted OR 1.67 per 5 units increase, 95% CI 1.31-2.14; p < 0.001). Definite bone metastases were confirmed in 44% of patients with bone uptake using an SUVmax ≥ 10 threshold.

CONCLUSIONS

[18F]F-PSMA-1007 PET/CT significantly enhances primary staging accuracy in prostate cancer, refining the D'Amico risk classification. The SUVmax ≥ 10 threshold allows differentiation between true bone metastases and unspecific bone uptake. Initial PSA levels significantly predict nodal metastases presence, optimizing treatment strategies and patient outcomes.