Long-Term PSA Control with Repeated Stereotactic Body Radiotherapy in a Patient with Oligometastatic Castration-Resistant Prostate Cancer.

Prostate cancer (PCa) is one of the most common malignancies and main causes of cancer death in Western countries. In the presence of metastatic disease, systemic treatment remains the main clinical option. However, since the introduction of highly sensitive imaging techniques, a new clinical 'entity' of metastatic patients with a limited number of lesions has been defined: oligometastatic patients. In this patient group, the use of stereotactic body radiotherapy (SBRT) or other local therapies against all active sites of disease revealed by 18F-choline positron emission tomography/computed tomography (PET/CT) could achieve sufficient prostate-specific antigen (PSA) control. However, a clear benefit of this procedure in terms of significant endpoints is yet to be demonstrated. This case report describes our experience with treating a castration-resistant PCa patient with 18F-choline PET/CT-guided SBRT. Because of the occurrence of 5 metachronous lesions over 4 years, the pattern of recurrence was defined by the local multidisciplinary team as oligometastatic disease, and the patient was treated with 5 courses of SBRT which yielded good PSA control. He started systemic therapy with abiraterone acetate almost 5 years after the diagnosis of recurrent PCa.