WEDNESDAY, Sept. 3 (HealthDay News) -- Taller men are at greater risk for prostate cancer and more likely to have cancer that progresses quickly, a new British study suggests.
The researchers doubt that height itself is the reason for the increased risk, but it may serve as a marker for something biological associated with developing cancer.
And other cancer experts said other risk factors for the disease are far more significant than being tall.
"We believe that factors that influence height -- not height itself -- could also influence cancer, said lead study researcher Luisa Zuccolo, of the University of Bristol Department of Social Medicine. "One plausible mechanism behind this association could be the insulin-like growth factor-1 system, which new lines of inquiry should address."
The findings were published in the September issue of the journal Cancer Epidemiology, Biomarkers & Prevention.
For the study, Zuccolo's team collected data on more than 9,000 men with and without prostate cancer and reviewed 57 relevant studies. The researchers found that the risk of developing prostate cancer increased about 6 percent for every 3.9 inches in height above the shortest men in the study. The average height of the men in the study was 5 feet, 7 inches.
In other words, a man who's a foot taller than the shortest person in the study would have a 19 percent increased risk of developing prostate cancer. The statistical data supporting this finding was weak, the researchers noted.
However, the researchers did find stronger evidence that height was associated with more aggressive tumors. For every 3.9 inches of increased height, the risk of a high-grade tumor rose 23 percent, Zuccolo's group found.
Compared with the main risk factors for prostate cancer -- such as aging, ethnicity and a family history of the disease -- the magnitude of the additional risk of being taller is small, Zuccolo said.
"We do not believe that height should interfere with preventive or clinical decisions in managing prostate cancer," Zuccolo said. "However, although not yet directly transferrable to medical practice, results from this research are of great scientific interest, especially given that so little is known of preventable causes of prostate cancer."
Dr. Anthony D'Amico, chief of radiation oncology at Brigham and Women's Hospital in Boston, said the study findings may be due to chance and not represent a real association.
"When you do a study like this, where you look at a very common attribute like height, eye color or skin color, and then you look at a very common disease like prostate cancer, you can find association that may just be by chance," he said.
There may be an association between height and a high-grade prostate cancer, D'Amico added. "But that association should not be taken to mean that if you are tall that there is something about being tall and getting high-grade prostate cancer. It could simply be that being tall is a surrogate for something else biological, which may be what is causing the effect."
"I don't think that this study convinces me, or makes me conclude that height in and of itself is a risk factor, and we should start screening earlier in men who are above a certain height," he said.
Dr. Stephen Freedland, an associate professor of urology and pathology and director of outcomes and translational research at the Duke Prostate Center at Duke University Medical Center, thinks other risk factors for prostate cancer are much more important than height.
"This is something I'd hate to see people get all worried about," he said. "If you eat right, take care of yourself, prevent yourself from being obese, I think you are doing the best you can. Everyone, short or tall, should be checked regularly."
Learn more about prostate cancer from the American Cancer Society.
SOURCES: Luisa Zuccolo, M.Sc., Department of Social Medicine, the University of Bristol, United Kingdom; Anthony D'Amico, M.D., Ph.D., chief, radiation oncology, Brigham and Women's Hospital, Boston; Stephen Freedland, M.D., associate professor of urology and pathology, director of outcomes and translational research, Urological Surgery, Duke Prostate Center, Duke University Medical Center, Durham, N.C.; September 2008, Cancer Epidemiology, Biomarkers & Prevention