New Treatments for Prostate Cancer

A Dutch multicenter randomized phase III trial, recruited 669 patients with stage T1b-T4N0M0 (free from cancer in the lymph nodes and no metastasis has occurred) prostate cancer and with baseline characteristics of median prostate-specific antigen (PSA) of 13.0 ng/ml. Sixty-three percent of patients had T1-2 tumors (smaller tumors localized to the prostate). Patients were divided into three prognostic groups of low, intermediate, and high risk, which included 18%, 27%, and 55% of patients, respectively. These groups were treated with either the higher dose of radiotherapy at 78 Gy or the conventional dose at 68 Gy. Some of the patients from the intermediate and high-risk groups were also receiving hormonal therapy (143 in total).

The goal of this study was to determine whether the higher dose of radiotherapy, 78Gy, offered more effective treatment of prostate cancer than the conventional dose at 68Gy.

Results indicated at five years, freedom from failure was significantly improved in patients receiving the 78Gy radiotherapy dose than those receiving the 68Gy dose. The intermediate risk patients experienced the most benefit from the higher dose treatment. The benefit in the high-risk group was smaller, and there was no gain in the low-risk group.

Speaking on behalf of the study authors at the Netherlands Cancer Institute (Amsterdam), Prof. Harry Bartelink commented, "This trial demonstrated that for radiotherapy of prostate cancer patients, higher radiation doses are more effective than conventional doses, and that these doses can be delivered safely.”

In the largest hormone therapy trial ever performed in prostate cancer patients, the Early Prostate Cancer program (EPC), findings indicated which patients would benefit from early anti-androgen therapy over a period of seven years. Patients received bicalutamide (anti-androgen) or placebo once daily plus standard care. The data revealed that in localized disease, there was no significant PFS or OS benefit but in locally advanced disease, bicalutamide considerably improved OS in patients in combination with radiotherapy.

In another ongoing study, a new immunotherapy agent, APC8015, is currently under investigation for the treatment of non-hormone responsive or androgen independent prostate cancer (AIPC). Early findings have been released from one of the two phase III trials that revealed a significant survival for APC8015-treated patients in the intent-to-treat group compared with placebo.

Study author, Dr. Tia Higano, from the University of Washington (Seattle, WA, USA), commented, "The combined data from these trials of APC8015 versus placebo suggest that immunotherapy might impact survival in men with androgen independent prostate cancer. APC8015 has a favorable safety profile.”





Related Links:
Netherlands Cancer Institute
University of Washington