Is it time to stop teaching breast self-examination?

The recommendation in CMAJ (1) “Is it time to stop teaching breast self-examination?”, has created consternation, confusion, and sometimes anger in Canadian women (2). This commentary involves two fatal errors, omission of the best available data from the review and making an assumption which leads to an absurd conclusion.

The latest data (2000) from the Canadian National Breast Screening Study reports on a genuinely scientific Canadian study. This is the only clinical trial with adequate follow up that is directly relevant to a recommendation for Canadian women (3). The failure to include this study in the review was a fatal error of omission.

The data for the 13th-year of a randomized trial involving almost 40,000 Canadian women, half of them screened by a combination of mammography and self examinations (“MA SE”) and the other half by self-examinations alone “SE”, showed that there were about the same number of deaths from breast cancer in both arms of the trial. Hence the results of the study can be succinctly expressed by the logical equation: “SE” = “MA SE”.

The unequivocal conclusion from this equation is this: Addition of mammography to self-examination did not result in any additional reduction in deaths from breast cancer,. Hence, the only logical recommendation that can be made from this result is that mammography should be dropped -- not that self-examination should be dropped. The best and most pertinent data on the topic gives no support for a recommendation to drop self-examination (a tacit assumption that “SE” = 0). Indeed, adding this assumption to the logical equation gives this nihilistic null conclusion (0 = 0): Earlier detection of breast cancer does not improve survivorship. If this conclusion seems silly, then it follows logically that the recommendation to drop self-examination in breast cancer is equally silly.

Irwin D. Bross, President
Biomedical Metatechnology Inc.
109 Maynard Drive
Amherst NY 14226
(716) 832-4200

REFERENCES

1. Nekhlyudov, L. and Fletcher, S. Is it time to stop teaching breast self-examination, CMAJ 2001; 164 (13): 1851-2.
2. Toronto Sun Letter to the Editor 2001 Saturday June 30.
3. Miller AB, To T, Barnes CJ, Wall C, Canadian National Breast Cancer Screening Study-2: 13-year results of a randomized trial in women aged 50-59 years. Journal of the National Cancer Institute 2000; 92 (18): 1490-99.