Combination hormone therapy improves prostate surgery outcome
MedWire News: Adding abiraterone acetate to standard androgen deprivation therapy for 6 months prior to surgical prostate removal, creates/produces an effective neoadjuvant regimen for some men with localized high-risk prostate cancer, suggests a US study.
The results, which were presented at the American Society of Clinical Oncology Annual Meeting in Chicago, Illinois, showed that add-on abiraterone acetate eliminated or nearly eliminated cancer in one-third of men undergoing surgery for localized, high-risk disease.
"For this proportion of patients with high-risk disease to have very little to no detectable cancer in the prostate after six months of therapy is dramatic," said lead researcher Mary-Ellen Taplin, from Harvard Medical School in Boston, Massachusetts, in a press statement.
Taplin and colleagues conducted a phase II trial consisting of two groups of men, aged a median of 58 years. Group A included 27 men who were administered leuprolide acetate and prednisone therapy for 12 weeks, followed by the addition of abiraterone acetate to the regimen for a further 12 weeks. Group B comprised 29 men who received the standard hormonal therapy plus abiraterone for the whole 24-week period.
After 24 weeks, all participants underwent radical prostatectomy and samples were analyzed for evidence of cancer.
The researchers found that 34% of the men in group B had either complete elimination (in three cases) or almost complete elimination (≤5 mm residual tumor in seven cases) of their cancer upon surgery. This compared with only 15% of those in group A, in which there was one case of complete elimination and three cases of near-complete elimination upon surgery.
Previous studies have shown the use of standard hormonal therapy alone, including leuprolide therapy, to be of little benefit to men with localized high-risk prostate cancer.
Men with this stage of disease tend to have a poor prognosis and experience metastasis despite aggressive treatment with available therapies.
"Our findings suggest that this combination therapy approach could improve outcomes for a substantial number of men, but larger, long-term trials are needed to confirm this approach," said Taplin.
By Sally Robertson