Early outcome prediction on 18F-fluorocholine PET/CT in metastatic castration-resistant prostate cancer patients treated with abiraterone

Abstract

Objective: We investigated the role of 18F-fluorocholine positron emission tomography/computed tomography (FCH-PET/CT) in the early evaluation of abiraterone and outcome prediction in patients with metastatic castration-resistant prostate cancer (CRPC).Patient and methods: Forty-three patients with metastatic CRPC progressing after docetaxel received abiraterone 1,000 mg daily with prednisone 5 mg twice daily. Patients were evaluated monthly for serological PSA response and safety. FCH-PET/CT was done at baseline and after 3 to 6 weeks. Univariate and multivariate Cox regression models addressed potential predictors of progression-free survival (PFS) and overall survival (OS).Results: Declines in PSA level of ≥50% were seen in 21 of 43 (49%) patients. Forty-two patients were evaluable for FCH-PET/CT response. FCH-PET/CT bone flare was observed in 4 of 42 (10%) evaluable patients. In univariate analysis, PSA decline and FCH-PET/CT response predicted PFS, while PSA decline and FCH-PET/CT (progression vs non progression) predicted OS. In multivariate analysis, only FCH-PET/CT (progression vs nonprogression) remained significant for PFS and OS (p = 0.022 and p = 0.027, respectively).Conclusion: Early FCH-PET/CT can predict clinical outcome in CRPC beyond PSA response. These data support further studies on FCH-PET/CT for abiraterone monitoring and outcome prediction in patients with CRPC.

11C-Choline PET/CT for restaging prostate cancer. Results from 4,426 scans in a single-centre patient series

“…Moreover, 68 % of the positive scans showed oligometastatic disease. Although it was not an aim of our study, we suggest that using a metabolic radiopharmaceutical, such as choline in castrate-resistant patients could have a role as a predictor of therapy response [32,33]. Indeed, despite the advent of new receptor radiotracers such as 68 Ga-PSMA [34], it seems from a theoretical perspective more appropriate to use a metabolic tracer in the assessment of response to therapy.…”

Can serial FCH-PET/CT scans predict the response to treatments in castrate resistant prostate cancer?

“…Conversely, Breeuwsma et al [23] did not find any significant differences in prostate cancer-specific survival on the basis of 11 C-choline PET/CT results. In our opinion, and by sharing the results by De Giorgi et al [9,10], radiolabelled choline PET, either 11 C or 18 F, might also be useful for monitoring the response to new therapies (such as taxanes or new anti-hormonal agents).Therefore, providing an appropriate support for future clinical trials. This study's limitations are typical for a retrospective study.…”

Evaluation of Prostate Cancer with 11C-Choline PET/CT for Treatment Planning, Response Assessment, and Prognosis

“…De Giorgi et al (19,46) assessed the usefulness of 18 F-choline PET/CT for evaluating the early response to treatment with abiraterone and enzalutamide in mCRPC patients. The authors concluded that a radiologic response, as assessed with 18 F-choline PET/ CT, was associated with more favorable overall survival than a PSA response of greater than or equal to 50% alone.…”

“…In 3 different patient series, 11 C-choline PET/CT led to a change in the decision-making process in approximately 50% of cases (15)(16)(17). Moreover, 11 C-choline PET/CT was recently proposed as a diagnostic tool for monitoring castration-resistant PCa (CRPC) patients treated with chemotherapy (18) and new ADT (19,20). The main drawback of 11 C-choline PET/CT is the relatively low sensitivity in patients with low PSA levels at the time of imaging (13,21,22).…”