AICR ScienceNow
Volume 14
Fall 2005
A man's risk of prostate cancer may be influenced by his habits as an adolescent. To investigate this hypothesis, AICR researcher Emily White, Ph.D., is looking at the weight, height and activity level of 37,000 men when they were teenagers.
More than 70 percent of all prostate cancers are diagnosed in men over age 65. But the disease may be encouraged by factors that exist decades before diagnosis, according to Dr. White, a Professor of Epidemiology at the University of Washington.
"Our hypothesis is that three factors - teenage obesity, teenage lack of activity and reaching maximum height at a young age - increase the risk of prostate cancer," Dr. White explains. The age at which a man reaches his maximum height is associated with his age at sexual maturation.
To investigate these possible links, Dr. White has surveyed more than 37,000 men, aged 50 to 76 years. She is analyzing how the incidence of prostate cancer among some of these men correlates with their weight at age 18, how physically active they were at age 18, and the age at which they reached their maximum height.
The data that Dr. White is using come from questionnaires the men filled out. The accuracy of the data appears high because several other studies compared the men's recall of their teenage weight and exercise with actual records from those years. The correlation between the historical data and the men's memory was excellent for weight and moderately good for physical exercise.
Breast Cancer Already Linked
Previous research has shown that the three variables in Dr. White's study - early obesity, lack of physical activity in early life and earlier sexual maturation - do increase the risk of breast cancer. This connection led Dr. White, who has studied breast cancer extensively, to think that these factors might inßuence prostate cancer as well. All three factors affect a person's secretion of hormones, and both breast and prostate cancer are considered hormone-sensitive cancers. In men, an early exposure to higher levels of testosterone and certain growth hormones may increase the risk of prostate cancer.
Dr. White's study is breaking new ground. Only one study has compared the prostate cancer rate in men with the age at which they reached their maximum height. Although the study found an almost three-fold increase in the rate of prostate cancer for men who reached their maximal height at a young age, versus those who matured later, it was a case-control study, which doesn't have the strength of evidence as a prospective study like Dr. White's.
More Reasons for a Healthy Weight and Exercise
Dr. White's research is especially cost-effective because it builds on data she had already gathered as part of another study. These data were originally collected in 2000-2002 as part of a large study in the state of Washington that addressed four kinds of cancer in both men and women. The original project gathered prostate cancer data for two years.
AICR's support allows Dr. White to extend the analysis for an additional two years. To ascertain the current total number of men in her population pool who have developed prostate cancer, Dr. White will use data collected by the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) cancer registry, which gathers data on all newly diagnosed cancers.
If her study shows a link between prostate cancer and teenage obesity and lack of exercise, Dr. White says, "One more disease will be added to the list of diseases and disorders that can be prevented, if you start at a young age maintaining a healthy weight and exercising." All active news articles
Volume 14
Fall 2005
Prostate Cancer Risk May Begin in Adolescence
More than 70 percent of all prostate cancers are diagnosed in men over age 65. But the disease may be encouraged by factors that exist decades before diagnosis, according to Dr. White, a Professor of Epidemiology at the University of Washington.
"Our hypothesis is that three factors - teenage obesity, teenage lack of activity and reaching maximum height at a young age - increase the risk of prostate cancer," Dr. White explains. The age at which a man reaches his maximum height is associated with his age at sexual maturation.
To investigate these possible links, Dr. White has surveyed more than 37,000 men, aged 50 to 76 years. She is analyzing how the incidence of prostate cancer among some of these men correlates with their weight at age 18, how physically active they were at age 18, and the age at which they reached their maximum height.
The data that Dr. White is using come from questionnaires the men filled out. The accuracy of the data appears high because several other studies compared the men's recall of their teenage weight and exercise with actual records from those years. The correlation between the historical data and the men's memory was excellent for weight and moderately good for physical exercise.
Breast Cancer Already Linked
Previous research has shown that the three variables in Dr. White's study - early obesity, lack of physical activity in early life and earlier sexual maturation - do increase the risk of breast cancer. This connection led Dr. White, who has studied breast cancer extensively, to think that these factors might inßuence prostate cancer as well. All three factors affect a person's secretion of hormones, and both breast and prostate cancer are considered hormone-sensitive cancers. In men, an early exposure to higher levels of testosterone and certain growth hormones may increase the risk of prostate cancer.
Dr. White's study is breaking new ground. Only one study has compared the prostate cancer rate in men with the age at which they reached their maximum height. Although the study found an almost three-fold increase in the rate of prostate cancer for men who reached their maximal height at a young age, versus those who matured later, it was a case-control study, which doesn't have the strength of evidence as a prospective study like Dr. White's.
More Reasons for a Healthy Weight and Exercise
Dr. White's research is especially cost-effective because it builds on data she had already gathered as part of another study. These data were originally collected in 2000-2002 as part of a large study in the state of Washington that addressed four kinds of cancer in both men and women. The original project gathered prostate cancer data for two years.
AICR's support allows Dr. White to extend the analysis for an additional two years. To ascertain the current total number of men in her population pool who have developed prostate cancer, Dr. White will use data collected by the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) cancer registry, which gathers data on all newly diagnosed cancers.
If her study shows a link between prostate cancer and teenage obesity and lack of exercise, Dr. White says, "One more disease will be added to the list of diseases and disorders that can be prevented, if you start at a young age maintaining a healthy weight and exercising." All active news articles