What is the recommended follow-up protocol for Prostate-Specific Antigen (PSA) checks after prostatectomy?

From the Guidelines

After a prostatectomy, PSA levels should be monitored every 3 to 12 months, with the first measurement taken within 3 to 12 months after surgery, as recommended by the American College of Radiology 1. The target PSA level following complete prostate removal should be "undetectable" (typically <0.1 ng/mL or <0.03 ng/mL depending on the assay used). Any detectable PSA after surgery may indicate residual prostate tissue or cancer recurrence. If PSA becomes detectable or shows a consistent rise (even within low ranges), more frequent monitoring and additional imaging studies like bone scans or specialized PET scans may be warranted. The timing of PSA checks is important because early detection of recurrence allows for more effective salvage treatment options. PSA has a half-life of about 2-3 days in the bloodstream, so levels should drop to undetectable within 4-6 weeks after complete prostate removal. Patients should always have their PSA tested at the same laboratory when possible to ensure consistency in measurements, as different assays may have different sensitivities and reference ranges.

Some key points to consider in the follow-up protocol include:

• The definition of biochemical recurrence (BCR) as a PSA level of >= 0.2 ng/mL confirmed on two successive assays, as per the National Comprehensive Cancer Network (NCCN) guidelines 1.
• The importance of monitoring PSA levels to detect recurrence early, as this allows for more effective salvage treatment options.
• The use of imaging studies such as bone scans or specialized PET scans to detect distant metastases or local residual disease.
• The consideration of targeted therapies for solitary or oligometastatic disease, rather than systemic therapies.

It is also important to note that the follow-up protocol may vary depending on the individual patient's risk factors and treatment history. For example, patients with a higher risk of recurrence may require more frequent PSA monitoring and imaging studies. Additionally, patients who have undergone radiation therapy may require a different follow-up protocol than those who have undergone surgery. Overall, the goal of the follow-up protocol is to detect recurrence early and provide effective treatment options to improve patient outcomes. As recommended by the Journal of the National Comprehensive Cancer Network, patients initially treated with intent to cure should have a serum PSA level measured every 6 to 12 months for the first 5 years and then rechecked annually 1. The American Cancer Society also provides guidelines for prostate cancer survivorship care, including the measurement of serum PSA levels every 6 to 12 months for the first 5 years, then rechecked annually thereafter 1.

From the Research

Follow-up Protocol for PSA Checks after Prostatectomy

The recommended follow-up protocol for Prostate-Specific Antigen (PSA) checks after prostatectomy involves regular monitoring of PSA levels to detect potential recurrence of prostate cancer.

• A first serum total PSA assay is recommended during the first three months after treatment 2.
• When PSA is detectable, PSA assay should be repeated three months later to confirm this elevation and to estimate the PSA doubling time (PSADT) 2.
• In the absence of residual cancer, PSA becomes undetectable by the first month after total prostatectomy: less than 0.1 ng/ml (or less than 0.07 ng/ml) for the ultrasensitive assay method and less than 0.2 ng/ml for the other methods 2.

PSA Screening Intervals

The frequency of PSA screening after radical prostatectomy can be tailored based on the patient's risk of recurrence.

• The longest advisable interval between checks of PSA levels is estimated to be four months within the first year after radical prostatectomy, and biannually or annually thereafter 3.
• Prostate specific antigen screening is sufficient to detect treatment failure after radical prostatectomy, irrespective of adjuvant hormone therapy 3.

Digital Rectal Exam (DRE) in Follow-up

The role of digital rectal exam (DRE) in the follow-up of patients after prostatectomy is limited when PSA is used.

• DRE can be omitted in the follow-up of radical retropubic prostatectomies until PSA becomes detectable 4.
• PSA is an average 14+/-11 months earlier in detecting relapse than DRE 4.

Impact of Persistent PSA

Persistent PSA after salvage radical prostatectomy represents a poor prognostic factor for recurrence.

• Patients with persistent PSA after salvage RP have worse oncologic outcomes, including higher rates of biochemical recurrence, metastasis, and death 5.
• Persistent PSA is an independent predictor for biochemical recurrence (BCR) and death after salvage RP 5.