Local therapy (LT) may offer a survival advantage to men diagnosed with metastatic prostate cancer (mPCa) who have specific characteristics, according to a new study.
Previous reports based on Surveillance, Epidemiology, and End Results (SEER) data left several unanswered questions. So a team from Vattikuti Urology Institute in Detroit led by Bjorn Loppenberg, MD, and Deepansh Dalela, MD, looked to the National Cancer Data Base 2004–2012 because it included younger men, comorbidity information, and usage of external beam radiation therapy (EBRT).
The investigators identified 15,501 men aged 35 years and older diagnosed with mPCa who received curative treatment within 6 months. About 9.5% of men received LT with radical prostatectomy, brachytherapy, and/or EBRT targeted to the prostate, with or without androgen deprivation therapy (ADT). The remaining patients received non-local therapy (NLT) consisting of watchful waiting, ADT, and/or EBRT not restricted to the prostate.
In agreement with previous research using SEER data, patients receiving LT had better 3-year overall mortality (OM)-free survival than men receiving NLT (69% vs 54%), according to results published online ahead of print in European Urology.
Interaction between predicted OM and LT status proved significant. The team graphed predicted risk of 3-year OM (based on age and Charlson comorbidity index of NLT patients) against actual survival of LT patients. The benefit of LT on OM declined as predicted OM risk rose. Specifically, the 3-year absolute improvement in OM-free survival was 15.7% for patients with a predicted OM risk of 20% or below compared with 0% for those with a predicted OM risk of 72% and above. The investigators provided this risk calculator to help clinicians determine which patients might benefit from LT.
“Men with mPCa at diagnosis benefit from LT in terms of OM,” concluded Drs Loppenberg and Dalela and colleagues. “This is largely affected by baseline characteristics. Specifically, patients with a relatively low tumor risk and good general health status appear to benefit the most.” Prospective research is warranted to corroborate the findings.