KLK3 and metastatic neoplasm: For the prostatectomized BCR patients with PSA between 0.2 and <1 ng/mL, 68Ga-PSMA showed an overall positivity rate of 80.6% (25/31) (p = 0.085; n.s.), for oligo-metastatic disease in 22.6% (7/31) (p = 0.001) and for local metastases in 38.7% (12/31) (p = 0.014).