A Prospective, Bicentric Evaluation of Fluciclovine PET-imaging in Patients with Prior Negative or Inconclusive PSMA-ligand PET

The REFINE study is a prospective, bicentric observational trial conducted at two specialized nuclear medicine centers in Germany to evaluate the technical performance of fluciclovine (18F) PET/CT imaging in a real-world clinical setting. Patients with prostate cancer recurrence after definitive treatment who previously underwent a negative or inconclusive PSMA PET/CT are enrolled and observed for 12 months. Each participant undergoes a fluciclovine PET/CT scan as part of their normal clinical routine, with all images pseudonymized and stored in a central database where three independent nuclear medicine physicians, blinded to the local site's interpretation, review each scan. In addition to the initial imaging, follow-up assessments are conducted at one month and 12 months to validate scan findings; a questionnaire sent to the referring physician at one month helps capture any changes in the intended treatment plan, while comprehensive follow-up data-including additional imaging studies, PSA levels, treatment outcomes, and histopathological findings when available-are collected at 12 months. This follow-up information serves as a composite reference standard to distinguish true positive lesions from false positives, with criteria based on changes in lesion size, response to treatment, and confirmatory imaging or biopsy results, as well as to identify any false negatives.

Inclusion criteria

• Patient is male and aged >18 years old.
• Patient with a history of localized adenocarcinoma of the prostate with prior curative intent treatment, experiencing BCR of hormone sensitive PCa, following prior treatment with one or more of the following: a) RP, b) RP plus adjuvant therapy, c) RT and/or androgen deprivation therapy [ADT].
• An elevated PSA, clinically suspicious for biochemically recurrent disease, that meets one of the following conditions: 1) Following RP with or without adjuvant therapy: PSA ≥0.2 ng/mL followed by a subsequent confirmatory PSA value ≥0.2 ng/mL and within the total range of 0.2 and 2 ng/ml. PSA must be measured at least 6 weeks after RP. 2) Following RT (e.g. radical radiotherapy or brachytherapy) as the primary treatment: nadir +2 ng/mL and within the total range of 2 and 4 ng/ml

Exclusion criteria

• Patients with any medical condition or circumstance (including receiving an investigational product) that the investigator believes may compromise the data collected or lead to a failure to fulfill the study requirements.
• Current or recent androgen deprivation therapy (ADT) within 3 months prior to the start of the study, which includes surgical orchidectomy, continuous or intermittent LHRH agonist/antagonist, and first-/second-generation anti androgen alone or combined with LHRH agonist/antagonist.