In recent years, the introduction of theranostic twins for specific diagnosis and treatment in patients with neuroendocrine tumors became a nuclear medicine success story. 64Cu/18F labeled prostate specific membrane antigen (PSMA) for molecular imaging with PET-CT and peptide radioligand therapy with 177Lu labeled PSMA inhibitors will favorably become the next theranostic twins in nuclear medicine history. 68Ga/ 64Cu/18F PSMA PET/CT detects metastatic prostate cancer with high diagnostic sensitivity and specificity. In addition, it can be used to select patients for radioligand therapy and evaluate therapy response. 64Cu-labeled radiopharmaceuticals such as 64Cu-PSMA, and 64Cu-somatostatin analogs are promising imaging tools in the assessment of primary disease and also in the detection of disease recurrence and to evaluate therapy response. The long half-life of 64Cu allows the distribution of the tracer to PET centers as a satellite concept, who otherwise has no access to 68Ga generators.