The advent of prostate-specific antigen (PSA) screening has increased early detection and treatment of prostate cancer. Most patients respond well to prostatectomy or localized radiation therapy if the cancer is diagnosed before it metastasizes. As a result, the mortality rate from prostate cancer has fallen significantly since the late 1980s.
Another consequence of early detection and treatment is that growing numbers of prostate cancer patients are diagnosed with "PSA failure"a biochemical recurrence of the cancer following prostatectomy or radiation therapy. Several definitions of PSA failure are used, but a patient is generally considered to be experiencing PSA failure if he has two consecutive increases in PSA after an initial post-treatment nadir.
PSA failure raises difficult issues for patients and physicians. Patients may experience anger, anxiety, or depression related to the recurrence of cancer following "curative" therapy. Furthermore, the clinical implications of the diagnosis are unclear. Does an increase in PSA correspond to a greater likelihood of developing symptoms or metastases? Treatment with androgen ablation is expensive and often has significant side effects, including hot flashes, impotence, weight gain, gynecomastia, and osteopenia. Still, many patients and physicians are uncomfortable leaving a rising PSA untreated.
Hormonal therapies result in decreased PSA levels, but the duration of the decline has not yet been established and varies significantly between patients. Several studies indicate that hormone therapy may delay the development of bony metastases or increase survival time following metastasis. Nevertheless, a conclusive link has not yet been established between androgen ablation therapy for PSA failure and improved clinical outcomes.
In the absence of clear outcomes-based evidence for or against hormonal therapy for PSA failure, researchers have started to examine the impact of hormonal therapy and watchful waiting on patients' health-related quality of life (HRQOL) and decision satisfaction. Several studies indicate that patients receiving androgen ablation therapy have poorer HRQOL than patients who do not, but few papers have focused specifically on HRQOL in PSA failure patients.
Since 2004, two ongoing observational studies have been collecting data on the relationship between treatment choice, HRQOL, and decision satisfaction in PSA failure patients. The Comprehensive Observational Multicenter Prostate Adenocarcinoma Registry (COMPARE), funded by Sanofi-Aventis, has enrolled more than 1,200 patients at hospitals and private urology practices across the United States. Patients have been tracked for up to 2 years following initial diagnosis. The study examines variations in clinical practices and outcomes, as well as the tolerability and HRQOL impact of treatment. Preliminary results from the study show significant variations in patterns of care and quality of life.
The PSA Failure study, led by Dr. Bennett at Northwestern University, looks at patterns of care for PSA failure patients at private, county, and VA hospitals. The study also uses data collected from questionnaires to analyze the impact of prostate cancer and treatment on HRQOL and decision satisfaction over 12 months. Researchers plan to enroll a total of 700 patients over the next several years.
1. Taplin ME: Biochemical (prostate-specific antigen) relapse: An oncologist's perspective. Rev Urol 5(suppl 3):S3-S13, 2003.
2. Dacal K et al: Quality of life in prostate patients taking androgen deprivation therapy. J Am Geriatric Soc 54(1):85-90, 2006.
3. Zagory JA et al: Race and health literacy associated variations in quality of life following treatment for veterans with newly diagnosed localized prostate cancer. Poster, ASCO Prostate Cancer Symposium, 2006.