In the United States, the Food and Drug Administration has approved for patients with suspected metastasis who are candidates for initial definitive therapy, patients with suspected recurrence based on elevated serum prostate-specific antigen (PSA) level, and for selection of patients with metastatic prostate cancer, for whom lutetium-177 (177Lu) vipivotide tetraxetan PSMA-directed therapy is indicated [28]. The gene discussed is KLK3; the disease is metastatic prostate carcinoma.