(RxWiki News) Monitoring return of prostate cancer using a blood test raises the question of what should be done when the blood test shows the cancer might be returning.
Prostate specific antigen (PSA) is measured regularly in the blood of men with prostate cancer. If PSA rises, it might signal that the prostate cancer is returning.
Since no standard guidelines tell doctors how to treat these patients, a research team looked at survival in groups of men with prostate cancer who received different treatments.
The researchers studied men who started hormone therapy immediately after prostate cancer relapse, as well as those who were treated at least two years later. Preliminary results from the study showed that the survival times of both groups were similar.
"Talk to your doctor about prostate cancer screening."
Lead study author Xabier Garcia-Albeniz, MD, from Harvard University School of Public Health in Boston, MA, presented these preliminary research findings at the annual meeting of the American Society of Clinical Oncology.
Dr. Garcia-Albeniz and team reviewed the records of 2,012 prostate cancer patients who had been treated with radical prostatectomy or radiation therapy with curative intention, and later showed a rise in their PSA.
The researchers split these patients into two groups. The immediate treatment group included those men who began hormone treatment (androgen deprivation therapy - ADT) within three months of their PSA relapse. The delayed group included patients who started hormone therapy at least two years after relapse.
In these patients, relapse was defined as a rise in each of three PSA measurements done one month apart.
Most men in the study were 69 years old, and a third of them had received radiation therapy.
The most common time to relapse for the men in the study was 27 months, with a range of 14 to 51 months. After relapse, the researchers studied the men for about 53 months.
The researchers estimated that 87.2 percent of the men in the delayed treatment group and 85.1 percent of the men in the immediate treatment group would be alive in five years.
The estimated survival time was not significantly different between the two treatment groups.
The authors commented that the results of their preliminary study suggested little to no benefit of immediate hormone treatment, compared to waiting for treatment.
Other factors that were not measured in the study, such as diet, blood pressure and healthy behavior, could have contributed to the results, the authors noted.
“Rising PSA levels trigger a lot of anxiety, and many men want to start treatment as soon as possible. These findings suggest that there may be no need to rush to ADT," Dr. Garcia-Albeniz remarked.
"If our result are confirmed in randomized trials, patients could feel more comfortable waiting until they develop symptoms or signs of cancer that are seen on a scan, before initiating ADT,” he continued.
Delaying ADT may result in better quality of life, since the therapy may result in sexual dysfunction, fatigue, loss of muscle mass, increased cholesterol, weight gain, and depression.
An abstract on the research was presented at the May 2014 meeting of the American Society for Clinical Oncology.
The authors declared no conflicts of interest.
The research was funded by the National Institutes of health, ASISA, Sociedad Espanola de Oncologia Medica and an educational grant from Abbott.