CRP Predicts Advanced PCa Outcomes
Findings support hypothesis that inflammation is an important determinant of response.
ORLANDO—Blood levels of C-reactive protein (CRP) independently predict survival in men with metastatic androgen-independent prostate cancer (AIPC), researchers conclude. CRP levels also predict the likelihood that patients will respond to therapy.
In this patient population, men with CRP levels above 8 mg/L are at three times increased risk of death than men with lower CPR levels, the investigators reported. Each doubling in CRP level is associated with a 27% increased risk of death and a 19% decrease in the likelihood of responding to therapy, as measured by PSA decline, according to researchers.
"Our finding is consistent with the hypothesis that inflammation is an important determinant of prostate cancer treatment response and resistance as well as overall survival," said lead investigator Tomasz M. Beer, MD, associate professor of medicine and director of prostate cancer research at Oregon Health & Sciences University Cancer Institute in Portland, Ore. He presented findings here at the third annual Prostate Cancer Symposium. The findings come from participants in the AIPC Study of Calcitriol Enhancing Taxotere (ASCENT), a phase II randomized study of 250 men with metastatic androgen-independent prostate cancer.
The study compared high-dose calcitriol plus docetaxel with placebo plus docetaxel. Dr. Beer and his colleagues analyzed blood sample findings from 160 participants (mean age 68 years) to examine the relationship between baseline inflammatory markers and patient outcomes. The median follow-up was 18.6 months.
Noting that CRP is a readily available blood test, Dr. Beer observed: "If these findings are confirmed, we'll have a powerful new prognostic factor available to physicians who treat patients with advanced prostate cancer." The findings provide insight into the biology of advanced prostate cancer and "give us a new area to investigate the role of inflammation in prostate cancer chemotherapy resistance and prostate cancer aggressiveness," Dr. Beer said.
The Prostate Cancer Symposium is sponsored by the American Society of Clinical Oncology, American Society of Therapeutic Radiology, and the Society for Urologic Oncology.