Breast self examination does not improve cancer survivalBMJ 2002; 325 doi: https://doi.org/10.1136/bmj.325.7368.793 (Published 12 October 2002) Cite this as: BMJ 2002;325:793
Teaching women breast self examination is not cost effective, nor does it lead to improvements in survival from breast cancer, according to a large, 10 year, randomised observational study conducted in Shanghai, China (J Natl Cancer Inst 2002;94:1445-57).
Breast self examinations did, however, lead to earlier detection of breast lesions and increased the number of biopsies for benign breast lumps.
David Thomas and Roberta Ray and colleagues from the Fred Hutchinson Cancer Research Center in Seattle, Washington, in conjunction with Dao Li Goa and colleagues from the Shanghai Textile Industry Bureau in Shanghai, China, conducted a study to examine the efficacy of breast self examination in reducing breast cancer mortality.
The study group was a cohort of 266064 female factory workers drawn from 519 textile factories in Shanghai between October 1989 and October 1991. The women were followed up until December 2000. A total of 132979 women were randomly assigned to be instructed in intensive self examination and 133085 women were assigned to a control group that did not receive any instruction.
Performing breast self examination did not lead to significant gains in survival. At the 10 year follow up point 154 women (0.12%) in the self examination group and 158 (0.12%) in the control group developed breast cancer and died. Of these deaths, 135 in the instruction group and 131 in the control group were deemed to be caused by the breast cancer itself. The number of breast cancers diagnosed overall was 1747, of which 864 were in the self examination group and 890 in the control group.
The cumulative risk ratio for women in the instruction group relative to the control group was 1.04 (95% confidence interval 0.82 to 1.33).
The number of breast biopsies performed for benign disease was considerably higher in the self examination group than in the control group: 2761 compared with 1505.
Treatment patterns were similar in the two groups. About 24% of women with breast cancer in each group were given radiation treatment, while 84% in the self examination group and 82% in the control group were treated with tamoxifen. Single and multiagent chemotherapy rates were also similar in the two groups: 6.1% and 7.1% for single agents and 80% and 81% for multiple agents. About 30% of each group used traditional Chinese medicines.
The authors concluded that, in general, teaching breast self examination is a waste of money—in developed countries and in more disadvantaged areas. In countries where mammography is available it is far superior and more specific in picking up cancerous lesions, they say. “In developing countries, where mammography screening is not available, it would not seem to be a good use of limited funds available for preventive services to promote the practice [of breast self examination],” they add.
Currently the US Preventive Health Services Task Force recommends neither for nor against self examination. The American Cancer Society still promotes the practice.
Advice to women to undertake breast self examination was abandoned over 10 years ago in the United Kingdom.