Diagnostic accuracy of F-18-Fluorocholine PET/CT and multiparametric MRI for prostate cancer

Background

Positron emission tomography (PET) using different positron-emitting radiopharmaceuticals has emerged as a promising new metabolic diagnostic tool for the evaluation of a variety of malignant diseases. Thus, we investigated the diagnostic efficacy of F-18-Fluorocholine positron emission tomography/computed tomography (PET/CT) and multiparametric magnetic resonance imaging (mpMRI) for the detection and localization of tumors within the prostate with the correlating histopathology as the standard of reference.

Methods

Forty patients with histologically proven prostate cancer underwent both F-18-Fluorocholine PET/CT and mpMRI before robot-assisted laparoscopic radical prostatectomy (RARP). The maximum standard uptake values and the tumor-to-background ratio were measured on a sextant basis. In brief, the sextants were defined as right apex, right middle, right base, left apex, left middle, and left base. For each tumor region, the correlation of the tumor localization based on the sextant in both F-18-Fluorocholine PET/CT and mpMRI scans with the histopathological results was determined.

Results

The correlation between both imaging modalities and RARP pathology representing (1) all cancer and (2) clinically significant cancer defined as a ≥ International Society of Urological Pathology grade of 2 showed that the sensitivity and the area under the curve (AUC) were higher for mpMRI than for F-18-Fluorocholine PET/CT. In contrast, F-18-Fluorocholine PET/CT had relatively higher specificity than mpMRI. Importantly, we found a very high AUC value of over 0.8 in both imaging modalities.

Conclusion

mpMRI had results superior to F-18-Fluorocholine PET/CT in assessing intraprostatic tumor localization. However, F-18-Fluorocholine PET/CT showed superiority in terms of specificity. Thus, using both modalities in conjunction could provide better treatment planning.