A long-term study by researchers at UCLA's Jonsson Comprehensive Cancer Center found that the three most common treatments for localized prostate cancer had significant impacts on patients' quality of life, a finding that could help guide doctors and patients in making treatment decisions.
The four-year study, which followed 475 men treated for early stage prostate cancer, also resulted in the development of "probability plots," gauges which can be used to predict when treatment side effects such as urinary incontinence, sexual dysfunction or bowel problems might return to normal, or whether the patient will ever fully recover. Such predictions could be used to determine whether further treatments or surgeries are needed to deal with adverse side effects, said Dr. John Gore, an urologist and the study's first author.
The study appears June 9 in the early online edition of the Journal of the National Cancer Institute.
"These probability plots are more helpful than the normal functional trajectory curves that are used," Gore said. "They allow people to point toward where the function level is currently and predict what it might be in the future. Is a patient's incontinence, for example, likely to get better? If not, the doctor and patients may agree to proceed with treatment options such as drugs or surgery."
The study is unique because it is not a cross-sectional review. Rather, researchers knew what a patient's baseline function was prior to treatment. That way, Gore said, they had a target to shoot for in judging recovery from side effects. The goal was to get the patient back to the function level experienced before treatment, if possible.
The researchers studied the quality of life in men who either underwent radical prostatectomy, implantation of radioactive seeds in their prostate gland or had external beam radiation therapy. The three treatment options rank about equally in survival outcomes for most men, so specific impacts on quality of life become paramount in making treatment decisions, said Dr. Mark Litwin, the study's senior author, a professor or urology and a researcher at UCLA's Jonsson Cancer Center.
"The good news is that the patients' overall mental and physical well-being were not profoundly affected by any of the three treatment choices," Litwin said. "That's good news for men with a diagnosis of prostate cancer hanging over their heads. In general, they'll be OK, no matter which of the three options they choose."
The study found that urinary incontinence was more common among patients who underwent prostatectomy than those who had seed implants, called brachytherapy, or external beam radiation. Sexual dysfunction was found in patients in all three treatment groups. Surgery patients were less likely to regain baseline sexual function than were patients who underwent external beam radiation. Bowel dysfunction and irritable bladder were more common after either form of radiation therapy than after prostatectomy.
Study patients were given comprehensive questionnaires to fill out before treatment to assess generic and prostate cancer-specific, health-related quality of life. Questionnaires were filled out again at one, two, four, eight, 12, 18, 24, 30, 36, 42 and 48 months after treatment to "capture maximal fluctuations in functional convalescence," the study states.
The most rapid change in the slope of patient recovery came very early after treatment, Gore said, either for better or worse. However, once more than two years had passed, the patient's recovery or decline had stabilized.
The study patients were diagnosed with the most common type of prostate cancer, low-risk, clinically localized disease. Many of the patients were older men and already were experiencing age-related functional issues such as erectile dysfunction, so each had individual baseline goals to achieve.
The study will allow oncologists to look at the patient, look at the characteristics of their cancer and determine what treatment will mostly likely help them to achieve their baseline health-related quality of life. For example, a patient with an existing irritable bladder condition should probably not receive external beam radiation because the treatment could exacerbate the underlying condition. A patient's acceptance of potential side effects also should be considered.
"Different men are bothered by different things, so it depends on what their baseline function is," Litwin said. "If a man is already impotent, for example, loss of sexual function won't be an issue in making a treatment decision."
Funding for the study came from the California Department of Health Services.
Prostate cancer is the most frequently diagnosed cancer in men and the leading cause of cancer deaths. This year, more than 186,300 men will be diagnosed cancer, and more than 28,000 men will die.
UCLA's Jonsson Comprehensive Cancer Center has more than 240 researchers and clinicians engaged in disease research, prevention, detection, control, treatment and education. One of the nation's largest comprehensive cancer centers, the Jonsson center is dedicated to promoting research and translating basic science into leading-edge clinical studies. In July 2008, the Jonsson Cancer Center was named among the top 10 cancer centers nationwide by U.S. News & World Report, a ranking it has held for nine consecutive years
Source: University of California, Los Angeles (UCLA)