Establishment of the optimal follow-up schedule after radical prostatectomy

Monitoring the serum level of prostate specific antigen (PSA) is indispensable for surveillance after radical therapy, and the aim of this study was to establish the optimal follow-up schedule.

We retrospectively reviewed the clinicopathological data of 1,010 consecutive patients who underwent radical prostatectomy. After excluding patients who received neoadjuvant or adjuvant therapy and those without a nadir PSA level<0.2ng/ml, the remaining 779 patients were enrolled. Biochemical recurrence (BCR) was defined as elevation of PSA to >0.2ng/ml. We investigated the PSA doubling time (PSA-DT) following BCR at various times after surgery.

During a mean follow-up of 8.8 years, BCR occurred in 180/779 patients. The annual BCR rate was 6% in the first year after surgery, 6% between 1 and 2 years, 3% between 2 and 3 years, 3% between 3 and 5 years, and 2% at >5 years postoperatively. During these periods, the minimum PSA-DT after BCR was 1.6, 2.4, 3.1, 6.1, and 6.4 months, respectively. These minimum PSA-DTs were used to determine the optimal follow-up interval during each period after surgery. If the baseline level is 0.1ng/ml, PSA should be measured at approximately 3-month intervals for the first year, at 4-month intervals between 1 and 2 years, at 6-month intervals between 2 and 3 years, and annually thereafter to definitely detect BCR before the serum PSA level exceeds 0.4ng/ml.

The PSA-DT following BCR varies according to the time after surgery. Our data on minimum PSA-DT values after BCR are useful for setting the optimal follow-up schedule.