From the Guidelines
A doubling of PSA is concerning and warrants medical attention, particularly if it occurs over a short period, as it may indicate prostate cancer recurrence or progression. PSA doubling time is an important marker that physicians use to assess prostate cancer risk and progression 1. If your PSA level has doubled, especially if it has occurred over a short period (less than 12 months), you should consult with your healthcare provider promptly for further evaluation. This is particularly important if you have a history of prostate cancer, as rapid PSA doubling time can indicate cancer recurrence or progression.
Some key factors to consider when evaluating the significance of PSA doubling include:
- Baseline PSA level
- Age
- Family history
- Previous prostate health issues
- Presence of symptoms
It's worth noting that PSA levels can also increase due to non-cancerous conditions such as prostatitis (inflammation of the prostate), benign prostatic hyperplasia (enlarged prostate), or recent ejaculation, prostate examination, or urinary tract infection. Your doctor will likely recommend additional testing, which may include a digital rectal examination, repeat PSA testing, imaging studies like MRI, or possibly a prostate biopsy depending on your specific situation and medical history. According to the most recent guidelines, novel positron emission tomography (PET)-CT scans (eg, fluciclovine, choline, PSMA) may be utilized in patients with PSA recurrence after failure of local therapy as an alternative to conventional imaging or in the setting of negative conventional imaging 1.
The primary rationale for utilizing these approaches relates to the fact that current standard of care (SOC) systemic treatments in metastatic hormone-sensitive prostate cancer (mHSPC) are based on such conventional imaging approaches rather than advanced/molecular imaging. However, it should be noted that these modalities infrequently detect metastases in the setting of early PSA recurrence (eg, PSA <5 ng/mL) 1.
From the FDA Drug Label
To interpret an isolated PSA value in a man treated with dutasteride for 3 months or more, the PSA value should be doubled for comparison with normal values in untreated men. Any confirmed increase from the lowest PSA value while on dutasteride may signal the presence of prostate cancer and should be evaluated, even if PSA levels are still within the normal range for men not taking a 5 alpha-reductase inhibitor.
A doubling of PSA is concerning and may signal the presence of prostate cancer. Any confirmed increase from the lowest PSA value while on dutasteride should be evaluated, even if PSA levels are still within the normal range for men not taking a 5 alpha-reductase inhibitor 2.
From the Research
PSA Doubling Time Concerns
- A doubling of PSA can be concerning, as it may indicate an increase in cancer volume 3.
- Studies have shown that PSA values increase with time in most patients with prostate cancer, and the rate of increase can be exponential 3.
- The doubling time of PSA can vary depending on the stage and grade of the cancer, with faster doubling times observed in patients with higher disease stages and grades 3.
Implications of PSA Doubling Time
- A slower PSA doubling time is associated with a lower risk of prostate cancer-specific mortality, while a faster doubling time is associated with a higher risk 4.
- The PSA doubling time can be used to inform treatment decisions and predict outcomes in patients with prostate cancer 3, 4.
- However, it is essential to consider other factors, such as age and comorbidity, when interpreting the results of PSA testing and determining the best course of treatment 4.
Diagnostic Value of PSA
- PSA testing is a valuable tool for detecting prostate cancer, and changes in PSA levels over time can provide information about tumor growth and response to treatment 3, 5.
- The combination of PSA testing and digital rectal examination (DRE) can improve the detection of prostate cancer, as these methods do not always detect the same malignant tumors 5.
- However, the diagnostic accuracy of DRE can vary depending on the population being tested and the criteria used to define a positive result 6, 7.