Although male breast cancer only accounts for less than one percent of all breast cancer, the fact that it increased in the U.S. by 26 percent between 1973 and 1998 is cause for concern. Breast cancer tumors in men tend to be detected later in life and at a later and more aggressive stage. The research, done at The University of Texas M. D. Anderson Cancer Center, will be published in the July 1 issue of the journal Cancer. Men are also more likely to have estrogen receptor positive tumors.
Although it’s difficult to do good research on male breast cancer with such a small number of cases, there’s every indication that excess estrogen is the primary culprit in men’s breast cancer, as it is in women’s breast cancer. Past studies have shown that men with gynecomastia, an enlargement of the male breast, have a higher than normal estrogen to androgen ratio, and others have hinted at an association between gynecomastia and breast cancer. The strongest risk factors for breast cancer in men are obesity and lack of exercise, which makes sense since fat cells in both men and women produce estrogen, and the more fat you have, the more estrogen you’ll make.
More than 100 prescription and over-the-counter drugs can cause gynecomastia, including ulcer and heartburn drugs such as Tagamet (cimetidine), Zantac (ranitidine) and Prilosec (omeprazole); antidepressants, including Prozac and Wellbutrin; antibiotics including isoniazid, ketoconazole and metronidazole and ciprofloxacin (Cipro); anti-anxiety drugs including valium and ativan, and heart drugs such as captopril and digitalis.
Other causes of gynecomastia include excess alcohol, marijuana, and the anabolic steroids used by athletes.
Although the chances that gynecomastia will become breast cancer are small, it should be taken as a symptom of hormonal imbalance, most specifically excess estrogen, or a high ratio of estrogen to androgens (male hormones).
For more information, please read Dr. Lee’s booklet, Hormone Balance for Men.
Published online in Cancer, the journal of the American Cancer Society, May 24, 2004, http://www3.interscience.wiley.com/cgi-bin/jhome/28741.