In the present analysis, we observed a higher frequency of patients with unfavourable prognostic characteristics such as pre-treatment with chemotherapy, lymphadenopathies, high bone metastatic tumour burden (depicted by the number of bone lesions at the bone scan and PSA levels), and low haemoglobin levels in patients treated with Ra-223 after the EMA amendment. Here, KLK3 is linked to metastatic neoplasm.