Histopathologic Correlation of Prostatic Adenocarcinoma on Radical Prostatectomy with Pre-Operative Anti-18F Fluorocyclobutyl-Carboxylic Acid Positron Emission Tomography/Computed Tomography.
David Schuster, Bowie Fei, Timothy Fox, Adeboye O Osunkoya. Emory University School of Medicine, Atlanta
Background: In the present era of active surveillance/deferred treatment and focal therapy for prostatic adenocarcinoma, accurate quantification and staging of prostatic adenocarcinoma clinically or pathologically has even more profound therapeutic and prognostic implications. Currently, there are no definitive imaging techniques for the detection or staging of locally advanced prostatic adenocarcinoma. Anti-18F fluorocyclobutyl-carboxylic acid (FACBC) is a synthetic L-leucine analog Positron Emission Tomography/Computed Tomography (PET/CT) radiotracer that has demonstrated promising results in brain tumors.
Design: Prior to surgery, 8 patients were injected with FACBC and underwent PET/CT imaging. All slides obtained from the radical prostatectomy specimens were reviewed. Areas of Gleason patterns 3, 4 and 5 were outlined with different colored markers. Foci with inflammation were also similarly outlined. All slides were then digitally scanned, to reconstruct the location of the dominant nodule /multifocal tumor nodules. Pathologic findings were subsequently correlated with FACBC PET/CT imaging.
Results: Mean patient age was 61 years (range: 53-70 years). Gleason scores were as follows; 3+4=7 (3 patients), 4+3=7 (4 patients) and 4+5=9 with ductal differentiation (1 patient). All patients had bilateral disease, with a definitive dominant tumor nodule. Pathologic stage was as follows; pT2c (2 patients), pT3a (4 patients), pT3b (2 patients). Mean tumor volume was 20% (range: 10-60%). Strong FACBC PET/CT uptake was demonstrated in the dominant tumor nodule in all cases. In the six patients with pT3a or pT3b disease, there was correlation between FACBC PET/CT uptake and pathology, with regards to laterality of extraprostatic extension and seminal vesicle involvement. There was no significant FACBC PET/CT uptake in areas of inflammation.
Conclusions: The preliminary findings of our study suggest that (a) FACBC PET/CT may be a very useful tool for clinical staging of patients with localized organ confined, or locally advanced prostatic adenocarcinoma (b) FACBC PET/CT may also have a role in targeted needle core biopsies in patients with prior negative or atypical biopsies, but with unexplained elevated PSA levels (c) It is also highly conceivable that FACBC PET/CT may be utilized in the selection of patients for definitive treatment versus active surveillance/deferred treatment even if they have small tumor volume on needle core biopsies.
Category: Genitourinary (including renal tumors)
Monday, February 28, 2011 1:00 PM
Poster Session II # 132, Monday Afternoon