PSA testing begins approximately 4 to 6 weeks after radical prostatectomy. PSA can also be called prostate-specific antigen, mainly used to assist in the diagnosis of malignant tumors, monitor the efficacy of treatment, determine the prognosis and tumor recurrence of an indicator, in the radical prostatectomy is usually carried out in about 4 to 6 weeks for the first test, mainly to determine the prostate in the postoperative recurrence of the situation, if two consecutive times the PSA appears to be elevated in the population should be considered to be recurring after the radical surgery If PSA is elevated twice in a row, the possibility of recurrence after radical surgery should be considered. The normal value of prostate-specific antigen serum t-PSA is <4.0 μg/L, the normal value of f-PSA is <0.8 μg/L, and the ratio of f-PSA/t-PSA is >0.25. If the indexes have abnormalities, it is necessary to carry out pathological biopsy to further determine whether there is a recurrence phenomenon.