Detection Rate and Clinical Impact of PET/CT with 18F-FACBC in Patients with Biochemical Recurrence of Prostate Cancer: A Retrospective Bicentric Study.

Luca Filippi,Ivan Cerio,Gabriele Brunotti,Agostino Chiaravalloti,Orazio Schillaci,Oreste Bagni,Carmelo Crisafulli,Franca Dore

doi:10.3390/biomedicines10010177

Abstract

Our aim was to assess the detection rate (DR) of positron emission computed tomography (PET/CT) with anti-1-amino-3-[18F]-flurocyclobutane-1-carboxylic acid (18F-FACBC) in patients with biochemical recurrence (BCR) from prostate cancer (PC). As a secondary endpoint, we evaluated 18F-FACBC PET/CT’s impact on patients management. Clinical records of 81 patients submitted to 18F-FACBC PET/CT due to PC BCR in two Italian Nuclear Medicine Units were retrospectively assessed. DR was gauged in the whole cohort and stratifying patients by discrete intervals of PSA levels. PET/CT’s impact on clinical management was scored as (1) major if it entailed an intermodality change (e.g., from systemic to loco-regional therapy); (2) minor if it led to an intramodality change (e.g., modified radiotherapy field). PET/CT’s DR resulted in 76.9% in the whole cohort, with a positive predictive value of 96.7%. Stratified by PSA quartile intervals, PET/CT’s DR was 66.7%, 71.4%, 78.9% and 90% for PSA 0.2–0.57 ng/mL, 0.58–0.99 ng/mL, 1–1.5 ng/mL and >1.5 ng/mL without significant difference among groups (p = 0.81). The most common sites of relapse were prostate bed and pelvic lymph nodes (59.3%). PET/CT impacted on clinical management in 33/81 cases (40.7%), leading to a major change in 30 subjects (90.9%). 18F-FACBC PET/CT localized recurrence in patients with BCR, with meaningful DR also at low PSA levels and significantly impacted on clinical management.

Highlights

Prostate cancer (PC) is a leading cause of cancer-related death worldwide [1]
We retrospectively reviewed clinical data of patients affected by PC biochemical recurrence (BCR) who were submitted to 18 F-FACBC (Axumin®, Advanced Accelerator Applications, Isernia, Italy)
radiation therapy (RT)) or RT/brachytherapy as a radical therapy; (4) 18 F-FACBC PET/CT performed due to evidence of BCR, defined as a prostate specific antigen (PSA) of 0.2 ng/mL or higher measured more than 6 weeks after prostatectomy or a PSA rise of 2 ng/mL or higher above nadir after RT [15]

Summary

Introduction

In patients with localized disease, radical treatment can be performed through prostatectomy or radiation therapy (RT). After a variable period of time, about 30–40% of patients present biochemical recurrence (BCR), defined, according to several parameters, as an increasing level of prostate specific antigen (PSA) following radical treatment [2,3]. Imaging plays a crucial role in BCR management, since determining whether it reflects local or distant recurrence is of utmost importance and has relevant clinical implications. In this scenario, positron emission computed tomography (PET/CT) has been successfully applied for the detection of metabolically active tumor tissue through the radiopharmaceutical choline, labeled with 18-fluorine (18 F) or 11-carbon (11 C) radionuclide.

Objectives

Methods

Findings

Conclusion