For a man, starting to go bald while in one's 20s signals a higher risk for prostate cancer than other men have, including those who go bald in middle age, a new study suggests.

Men with prostate cancer were twice as likely as healthy men to have started balding at age 20, the study said. However, the researchers found no link between prostate cancer risk and balding at ages 30 and 40, said study researcher Dr. Michael Yassa, a radiation oncologist at Maisonneuve-Rosemont Hospital in Montreal.

"This information should be in the minds of patients and physicians when discussing the pros and cons of prostate cancer screening," Yassa told MyHealthNewsDaily.

Male pattern baldness, technically known as androgenetic alopecia, is associated with male hormones called androgens. Men who are bald have high levels of an androgen called dihydrotestosterone, which is the active form of testosterone in the body, he said.

But men with a full head of hair have reduced levels of dihydrotestosterone, Yassa said. In fact, drugs like finasteride (Propecia ) work by blocking the conversion of testosterone to dihydrotestosterone.

And higher levels of androgens can also increase a man's risk of prostate cancer, he said. For example, blocking the actions of androgens in the body is used as a treatment for prostate cancer, Yassa said.

The study was published online today (Feb. 15) in the journal Annals of Oncology.

Baldness and cancer risks

Researchers studied the hair-loss histories of 388 men with prostate cancer , and 281 healthy men. The men with prostate cancer had been diagnosed between the ages of 47 and 84.

Researchers showed four photos to the men and asked them to choose which most closely resembled their hair loss at ages 20, 30 and 40. The first photo showed no balding (stage I balding); the second showed a receding hairline (stage II balding); the third showed a bald patch at the top of the head (stage III balding) and the fourth showed a combination of the receding hairline and the bald patch at the top of the head (stage IV balding).

According to the responses, 37 men with prostate cancer had stage II, III or IV balding at age 20, while only 14 of the men without the cancer did. That showed that any balding at age 20 is associated with a doubled risk of prostate cancer later in life, researchers said.

Implications of balding

The findings mean that men who start balding in their 20s should consider getting a prostate-specific antigen (PSA) test to screen for prostate cancer, said study researcher Philippe Giraud, radiation oncology professor at the Paris Descartes University in France.

Men can get a PSA test starting at age 40, according to the Mayo Clinic, though no U.S. organization has issued guidelines regarding this screening test. The researchers said men who started balding early should consider getting tested, or having the test done earlier than men with no risk factors.

However, more research is needed to better define the age of balding at which cancer risks begin, Giraud said.

Future studies with "more patients could improve evaluation of the possible link between baldness and prostate cancer, and refine the risk after 30 [years old]," Giraud told MyHealthNewsDaily.

Previous studies made conflicting associations between prostate cancer risk and balding. One study published last year in the journal Cancer Epidemiology of nearly 2,000 men showed that those who went bald by age 30 had a 29 percent lower risk of developing prostate cancer than men who had all their hair at that age.

Yassa said he's not sure why the results of the 2010 study and his study are different, but he did point out that some past research supports his findings. For example, a 2000 study of more than 200 men, reported in the journal Cancer Epidemiology, Biomarkers & Prevention, showed that men who were bald had a 50 percent increased risk of developing prostate cancer.

Pass it on: Men who bald at age 20 may have an increased risk of prostate cancer later in life.

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