Is losing your hair a sign of cancer?

Men with a specific pattern of hair loss at age 45 may be more likely to develop aggressive prostate cancer later in life, according to a new study published in the Journal of Clinical Oncology.

Using data from the U.S. Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial, researchers analyzed the self-reported hair-loss patterns of nearly 40,000 men between the ages of 55 and 74.

They found that men who recalled having male pattern baldness at age 45 were 40 percent more likely to develop a form of aggressive prostate cancer when they got older compared to men who weren’t balding.

However, no type of baldness was linked to a higher rate of overall cancer, and male-pattern baldness was not linked to non-aggressive prostate cancer, the researchers noted.

“Our study found an increased risk for aggressive prostate cancer only in men with a very specific pattern of hair loss, baldness at the front and moderate hair-thinning on the crown of the head, at the age of 45,” said lead study author Michael B. Cook, in a statement.

Previous studies had already found frontal baldness to be associated with higher odds of developing high-stage, high-grade tumors, but only among black males diagnosed with prostate cancer younger than age 60.

The researchers suspect the link is due to male androgens, or sex hormones. Testosterone and an androgen derived from testosterone – called dihydrotestosterone (DHT) – are linked to both male-pattern baldness and to the progression of prostate cancer, they said.

But if you’re one of the millions of American men experiencing hair loss, don’t panic, says Dr. Hosam Zakariya, an internal medicine physician with Advocate Medical Group in Mundelein, Ill.

“While the results are interesting, it’s too soon to apply these findings to your individual risk for prostate cancer,” Dr. Zakariya says. “However, if you’re concerned, as always, talk to your doctor.”