(CBS) Breast cancer is about 100 times less common in men than in women. But the fact that breast cancer is so rare in men means that many guys don't get diagnosed until after their malignancy has reached an advanced stage. So say scientists behind a provocative new study published in the Journal of Clinical Oncology.
For the study, researchers looked at breast cancer incidence and survival in men and women in Denmark, Finland, Geneva, Norway, Singapore, and Sweden over the past 40 years - a total of 459,846 women and 2,665 men.
On average, men with breast cancer diagnosed later than women (69.6 years of age vs. 61.7 years of age) and were more likely to have advanced cancer at the time of diagnosis. But once the researchers corrected for factors including stage of cancer at diagnosis and treatment used, men were shown to be less likely to die than comparable female breast cancer patients.
"It's not surprising that men with breast cancer present with later stages," Dr. Susan Dent of the Ottawa Hospital Cancer Center in Canada told Reuters. "That's just because the awareness of the fact that breast cancer can occur in men is not as acute. Men aren't as likely to think of it, and health care providers aren't as likely to think of men having breast cancer." Dr. Dent wasn't involved in the study.
Just how common is breast cancer in men? The American Cancer Society says a man's lifetime risk is about 1 in 1,000. In 2011, the society says, about 2,140 American men will be diagnosed with breast cancer and about 450 will die of the disease. Average age of diagnosis? About 68.
In addition to advancing age, risk factors for breast cancer in men include obesity, heavy alcohol consumption, liver cirrhosis, treatment with estrogen for prostate cancer, a hereditary condition known as Klinefelter syndrome, and a strong family history of breast cancer (in men or women) or ovarian cancer. Men with such a family history might want to speak with a doctor about genetic testing to check for a mutant BRCA gene.
Symptoms of breast cancer in men include a lump or swelling (usually painless), nipple retraction, redness of the nipple or breast skin, skin dimpling or puckering, and a discharge from the nipple.
The American Cancer Society has more on breast cancer in men.