Earlier Docetaxel Beneficial
In a study presented at the 2015 American Society of Clinical Oncology annual meeting in Chicago, IL, researchers found that administering docetaxel chemotherapy at the same time as starting long-term hormone therapy for the first time can improve survival in men with high-risk locally advanced or metastatic PCa.3
Nicholas D. James, MD, director of the Cancer Research Unit at the University of Warwick in Coventry, United Kingdom, and colleagues randomly assigned 2,962 patients (61% with metastatic disease) into one of four treatment arms: standard of care (SOC), SOC plus docetaxel, SOC plus zoledronic acid, and SOC plus docetaxel and zoledronic acid.
The median follow-up was 42 months. Compared with patients in the SOC-only group, those in the SOC plus docetaxel group and SOC plus docetaxel and zoledronic acid group had a 24% and 19% decreased risk of death, respectively.
Survival did not differ significantly among patients in the SOC plus zoledronic acid group. Median survival in the SOC-only group was 67 months compared with 77 among subjects in the SOC plus docetaxel group.
Continuous Versus Intermittent ADT
In another study that could help guide patient management, researchers documented that intermittent and continuous ADT were associated with similar efficacy, tolerability, and quality of life among patients with relapsing or locally advanced PCa.4
In a prospective phase 3b open-label study, 701 patients with locally advanced or relapsing non-metastatic PCa after radical prostatectomy or radiotherapy were randomly assigned to receive either continuous or intermittent ADT with leuprorelin for 36 months. Inclusion criteria required a Gleason score of 6 or higher and a life expectancy of 5 years or more.
A total of 58% of patients had locally advanced PCa and 42% had relapsing non-metastatic PCa. The continuous and intermittent groups were comparable at baseline. Patients were followed at 6-month intervals for 18 months.
Results showed that time to PSA progression (the primary endpoint), PSA progression-free survival, mean PSA levels over time, quality of life, and overall survival did not differ significantly between the groups. The estimated 5-year overall survival rates for the continuous and intermittent ADT groups were 85% and 81.8%, a non-significant difference.
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Most adverse events (AEs) were mild or moderate; the most common were hot flushes and hypertension. In addition, when the researchers compared AEs in patients with locally advanced PCa versus relapsing PCa at baseline, they found no differences between continuous or intermittent ADT with respect to the number of AEs, serious AEs, or AEs leading to drug discontinuation.
Recent studies in patients with PCa evaluating the effects of early ADT, salvage ADT, early administration of docetaxel, and continuous versus intermittent administration of ADT have shed some light regarding best treatment options in different PCa patient populations, and may offer a guide for patient therapy in the future. Further studies are still required in order to optimize outcomes of patients with PCa.
- Freedland S, Howard L, Amling C, et al. Does early androgen therapy after biochemical recurrence following radical prostectomy increase overall survival? Results from SEARCH [abstract MP82-15]. Presented at the American Urological Association 2015 annual meeting.
- Sagalovich D, Leapman M, Sfakianos, et al. Timing of salvage androgen deprivation therapy following prostate radiotherapy does not adversely affect all-cause or prostate cancer specific survival [abstract MP87-04]. Presented at the American Urological Association 2015 annual meeting.
- James ND, Sydes MR, Mason MD, et al. Docetaxel and/or zoledronic acid for hormone-naïve prostate cancer: first overall survival results from STAMPEDE (NCT00268476). J Clin Oncol. 2015;33 (suppl; abstract 5001).
- Schulman C, Cornel E, Matveev V, et al. Intermittent versus continuous androgen deprivation in patients with relapsing or locally advanced prostate cancer: a phase 3b randomized study (ICELAND) [abstract MP73-20]. Presented at the American Urological Association 2015 annual meeting.