However, in this trial the PSA level was monitored every 2–3 months, whereas the kinetics of serum PSA analyzed monthly during the first few months of abiraterone is associated with PSA flare in nearly 10% of these patients, which could impair the early evaluation of PSA response [16], The impact of FCH-PET/CT could be even more relevant for CRPC with no reliable serum biomarker, as is the case of bulky metastatic disease with low serum PSA levels. The gene discussed is KLK3; the disease is metastatic neoplasm.