National Post (National Edition)
Baldness may be prostate cancer clue
As if male-pattern baldness were not already a curse for self-conscious men everywhere, a Canadian research team is suggesting it could also strongly predict the risk of getting prostate cancer, and more serious cases of the disease.
The University of Toronto scientists even argue the extent of someone’s hair loss might help doctors decide whether to carry out painful biopsies in marginal cases.
And, they say, it seems to be a much better predictor of risk than commercial genetic tests that cost thousands of dollars each.
“We were trying to be a bit provocative (about the genetic tests), but it’s true,” said Dr. Neil Fleshner, head of urology at Toronto’s Princess Margaret Cancer Centre and co-author of the study. “If you get it (baldness) early and you get a lot of it, those people are particularly at risk.”
There is no suggestion that being bald itself causes prostate cancer. But Fleshner and his colleagues theorize that high levels of male hormones like testosterone are linked to both vanishing hair and the prostate malignancy.
The most significant aspect of the association, in fact, may be what it says about the biological mechanisms behind prostate cancer, the second-most-common type to afflict men, he said.
Unusual as the juxtaposition of hair loss and cancer seems to be, theirs was not the first to make the link.
A study published last year by the U.S. National Cancer Institute found that men with moderate baldness were 83 per cent — just under two times — more likely than those who weren’t bald to die from prostate cancer.
The Toronto research was conducted among almost 400 men who had come to Princess Margaret for a prostate biopsy.
They were asked to rate their degree of baldness at both age 30 and currently on something called the Norwood scale, with scores for hair loss ranging from zero — for no balding — to four — severe balding at the “vertex,” or crown. A researcher verified the current score.
Just under half the men were diagnosed with cancer. And the researchers found that the less hair someone had, the greater the chance he had cancer.
Those who scored a three on the Norwood scale were just under three times as likely to have a malignant tumour as the non-bald, while those with a four on the scale were more than three times as likely to have cancer.
The greatly increased risk, and evidence of a “dose-response” relationship — the chances of having cancer increased steadily with the degree of hair loss — points to there being a real connection, said Fleshner.
The study also found that patients with the most advanced hair loss — a score of four — were three times as likely to suffer from highergrade prostate cancer.
Fleshner suggested that doctors who are unsure of whether to take samples of the prostate to analyze for cancer — the current PSA blood tests are a notoriously imprecise indicator — could look to the patient’s scalp for help.
“If they’re on the borderline of whether to do a biopsy … you may want to take into account the added risk factor of the man’s head of hair,” he said.
Controversy surrounds prostate-cancer diagnosis, with concern that many men undergo treatment — and face the potential of serious side effects — for cancers that would not have been life-threatening.
The National Cancer Institute study, though, suggested that more investigation was needed before using malepattern baldness in cancer screening, partly because hair loss is so widespread among men.
Meanwhile, baldness does seem to be a stronger sign of prostate-cancer odds than genetic tests now available for purchase, which can point to at most a two-fold greater risk, said Fleshner.
Some research has found that both men with malepattern baldness and with prostate cancer have elevated levels of testosterone, although the evidence is not conclusive.