The results were obtained after two consecutive studies, a 2003 study of more than 120,000 Russian women and a 2002 study of more than 266,000 Chinese women. According to both the studies, the women who did breast self-exams were nearly twice as likely to get breast biopsies, many of which turned out not to show cancer.
Writing in the Tuesday issue of The Cochrane Library, researchers found that breast self-exams made no difference to the groups' breast cancer survival rates, and it boosted the biopsy rate.
Researchers added that the results do not rule out self-exams completely but should only be considered as an option. After age 50, researchers say an annual mammogram can reduce the risk of breast cancer death by about 30 percent to 40 percent.
Breast self-examination was widely discussed in the 1990s as a useful technique to detect breast cancer at an earlier stage. In 2003, the American Cancer Society relegated the self-exam to an "optional" method of detecting breast cancer, citing self awareness as more important than structured self exams based.
Worldwide, breast cancer is the second most common type of cancer after lung cancer and the fifth most common cause of cancer death.
Women in the United States have the highest incidence rates of breast cancer in the world; 141 among white women and 122 among African American women.
