Conclusions
This is the first VA study to compare the efficacy of Ra-223 and other therapies in metastatic CRPC between AO+ and AO- veterans. AO+ veterans were diagnosed at a younger age and had higher Gleason scores. There was no statistical difference between AO+ and AO- veterans in terms of time to SRE, PSA progression, and bone and ALP progression even though there was a trend of shorter duration in AO+ veterans. There was no median survival difference between veterans who received Ra-223 first vs Ra-223 later as well as between AO+ and AO- veterans, but there was a trend of worse survival in veteran who received Ra-223 later and AO+ veterans.
This study showed that AO+ veterans have a shorter duration of response to therapy and shorter median survival compared with that of AO- veterans. We recommend that veterans should get Ra-223 in the first-line setting rather than after hormonal therapy and chemotherapy because their marrows are still intact. We need to investigate further whether veterans that exposed to carcinogen 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) may have different molecular biology and as such may cause inferior efficacy in the treatment of prostate carcinoma.
