Pomegranate juice may slow the progression of prostate cancer, according to long-term research results recently presented at the 104 th Annual Scientific Meeting of the American Urological Association.
One of the screening tests used for finding prostate cancer early is the PSA test. PSA stands for prostate-specific antigen, a protein that's produced by the prostate gland. Normally, men have a low level of PSA in their blood, but prostate cancer (as well as relatively benign conditions like benign prostate hyperplasia (BPH) and prostatitis) can increase the levels substantially. Researchers frequently track the increase in PSA as an indicator of how quickly a cancer may be growing. "A very long doubling time is a good thing", explained Christopher Amling, MD, a spokesman for the American Urological Assocation. "A very rapid doubling time is a surrogate marker for mestatizing. The shorter the doubling time, the more rapidly the cancer is growing".
In this study, researchers studied men who had been treated for prostate cancer with either surgery or radiation and monitored the "success" of the treatment by watching how long it took for their PSA's to double. They studied 48 men who had an average "doubling time" of 15 months at the beginning of the study. The men were given 8 ounces of pomegranate juice daily.
The study began in 2003 and is now in its sixth year. When researchers recently compared men who dropped out of the study with men who are still participating, they found that the active patients now had an average doubling time of 54 months. An earlier paper (in Clinical Cancer Research, 2006(1)) showed that about 1/3 of the men treated with pomegranate juice actually experienced a decline in their PSA, while 83% of the men showed a lengthening of their PSA doubling time, indicating that the growth of the cancer had significantly slowed. The current paper presented at the Urological Society is an update of the ongoing research, and confirms the positive results. "The average doubling time is now closer to 60 months", Dr. Amling told me.
The researchers don't know exactly what compounds found in pomegranate juice are responsible for the results. "We think it's the polyphenol antioxidants", Dr. Amling told me, "but we haven't tried to isolate any one compound". He told me that while some researchers are trying to isolate the active ingredients, the individual ingredients themselves don't seem to work as well as the actual juice which contains dozens of plant based chemicals that may have a synergistic effect.
Does this mean that pomegranate juice can prevent prostate cancer? That's a claim no responsible researcher is willing to make- yet- though it certainly appears to have anti-cancer activity. "Pomegranate juice looks very promising as a non-toxic strategy for slowing the progression of prostate cancer", Dr. Amling said. "For a significant number of people, the benefits are enormous and durable".
The study used Pom Wonderful, a widely available brand of Pomegranate Juice.
Pantuck, et al "Phase ll Study of Pomegranate Juice for Men with Rising Prostate-Specific Antigen following Surgery or Radiation for Prostate Cancer", Clin Cancer Res 2006 Jul 1: 12 (13): 4018-26