Careful physical breast examination is as effective as screening mammography in reducing mortality from breast cancer in women aged over 50, according to a controversial new study (Journal of the National Cancer Institute 2000:92:1490-9).

The second Canadian national breast screening study found that mammography detected breast cancers earlier than physical breast examination, but surprisingly, earlier detection did not translate into a survival advantage.

The Canadian study, led by Dr Anthony Miller and colleagues at the University of Toronto, followed 39 405 women aged 50-59. Only women who were not pregnant, had no history of breast cancer, and had not had mammography within the previous 12 months were eligible for enrolment.

The women were recruited from six provinces and 15 medical centres between 1980 and 1985 and were randomised into two arms: 19 711 women received both mammography and physical breast examinations by nurses or doctors, and 19 694 women received physical breast examinations alone.

All the women were taught to examine their breasts and were followed via record linkage with the Canadian national cancer registry and the national …