From the Guidelines
An ultrasensitive PSA level less than 0.006 ng/mL is a highly favorable result, indicating no detectable prostate-specific antigen in the bloodstream and suggesting a very low risk of prostate cancer or recurrence. This value is below the threshold of detection for most ultrasensitive PSA assays, and it is consistent with the expected outcome after radical prostatectomy or in men with a very low risk of prostate cancer 1.
Key Points to Consider
- The ultrasensitive PSA test is designed to detect extremely small amounts of PSA, making it useful for post-prostatectomy monitoring or for assessing the risk of prostate cancer in men with a family history or other risk factors.
- A PSA level less than 0.006 ng/mL suggests that there is no significant prostate tissue present, which is consistent with the expected outcome after radical prostatectomy 1.
- Continued monitoring with regular PSA tests is still recommended, typically every 3-6 months for the first few years after surgery, then annually thereafter, to detect any potential recurrence early.
- Any future rise in PSA, particularly above 0.1-0.2 ng/mL, would warrant further investigation as it could indicate biochemical recurrence 1.
Clinical Implications
The clinical implications of an ultrasensitive PSA level less than 0.006 ng/mL are significant, as it suggests a very low risk of prostate cancer or recurrence. However, it is essential to continue monitoring PSA levels regularly to detect any potential changes or recurrence early. The use of ultrasensitive PSA tests has improved the detection of prostate cancer recurrence, allowing for timely intervention and potentially improving outcomes 1.
From the Research
Ultrasensitive PSA Levels
- Ultrasensitive PSA levels less than 0.006 ng/mL are considered extremely low and may indicate a favorable prognosis in patients with prostate cancer 2, 3.
- Studies have shown that patients with undetectable ultrasensitive PSA levels after radical prostatectomy have a lower risk of disease recurrence and improved biochemical recurrence-free survival 2, 4, 3.
- The use of ultrasensitive PSA assays can detect prostate cancer recurrence earlier than standard PSA assays, but the specificity of detectable ultrasensitive PSA is low 4.
Prognostic Significance
- Undetectable ultrasensitive PSA nadir after radical prostatectomy is a useful predictor of biochemical recurrence-free survival, along with other factors such as preoperative PSA level, pathologic stage, and pathologic Gleason score 2.
- Patients with ultralow PSA levels (<0.02 ng/mL) have been shown to have improved oncological outcomes, including overall survival and radiographic progression-free survival, in the context of metastatic hormone-sensitive prostate cancer treated with Apalutamide 5.
Clinical Implications
- The use of ultrasensitive PSA assays may enable earlier detection of cancer recurrence and inform decision-making regarding adjuvant and salvage therapy 4, 3.
- However, the lack of evidence demonstrating improved survival after early salvage therapy prompted by ultrasensitive PSA surveillance highlights the need for further research in this area 4.