Patients with metastatic prostate cancer whose prostate-specific antigen (PSA) levels drop below 0.2 ng/mL after treatment have significantly better survival outcomes, according to a real-world study published in Cancer.
Researchers analysed Veterans Health Administration data on 4,890 patients who received testosterone deprivation therapy with or without additional treatments between 2018 and 2023 for metastatic hormone-sensitive prostate cancer. Over a median follow-up of approximately two years, 896 patients died.
Patients whose PSA levels dropped below 0.2 ng/mL within nine months of starting treatment were 54% less likely to die than those whose levels did not reach this threshold. This survival benefit was observed regardless of whether patients also achieved a 90% or greater PSA decline. Notably, patients who had at least a 90% PSA reduction but did not reach the 0.2 ng/mL threshold showed no improvement in survival.
Whilst multiple phase 3 clinical trials have identified PSA below 0.2 ng/mL as the optimal cutoff for determining prognosis, real-world data have been lacking. Physicians often use other metrics, such as percentage of PSA decline, to assess treatment response.
The findings suggest that patients who do not achieve a PSA drop below 0.2 ng/mL could be candidates for more aggressive treatments. Additionally, patients receiving testosterone deprivation therapy combined with another testosterone-blocking drug were more likely to reach the target threshold.
Corresponding author Dr Stephen Freedland, professor of urology at Cedars-Sinai and staff physician at the Durham VA Medical Center, stated that clinicians should target PSA below 0.2 ng/mL as the metric of success to optimise outcomes for patients with metastatic prostate cancer.
Source: News Medical / Wiley (Cancer, 2026)
