Breast self-examination and survival from breast cancer

Abstract

The relationship between breast self-examination (BSE) and survival was evaluated in 2093 women with breast cancer newly diagnosed between June 1975 and February 1979. In this population self-examiners were younger, more educated, and more likely to be white, premenopausal, and married than nonexaminers. Self-examiners also tended to seek medical care more rapidly and to have earlier stages of disease at diagnosis. Five years after diagnosis, the cumulative observed survival rates from breast cancer were 76.7% among self-examiners and 60.9% among nonexaminers (P less than 0.0001). In a multivariate analysis known sociodemographic and treatment confounders accounted for 25% of the excess of breast cancer deaths among nonexaminers. Approximately half of the remaining survival differential was attributable to the more limited disease among selfexaminers. The residual association between BSE and survival may be related to uncontrolled effects of stage or other unrecognized confounders.

Breast self-examination and death from breast cancer: a meta-analysis

“…Several studies have shown that various characteristics that are likely to be associated with dying from breast cancer were also associated with BSE practice, but analyses adjusting for the potential effect of such confounding on mortality were not reported. Women who practised BSE tended to be younger, premenopausal and of a higher socioeconomic status (Smith et al, 1980;Feldman et al, 1981;Tamburini et al, 1981;Huguley et al, 1988;Le Geyte et al, 1992;Auvinen et al, 1996). Much of the reduction in mortality observed in these studies might therefore be explained by a combination of these and other confounding factors as well as the aforementioned biases, rather than a real effect of BSE.…”

“…Relative risk of having advanced breast cancer in BSE vs non-BSE groups Practise BSE vs do not practise BSE Foster, 1984Huguley, 1988Kurebayashi, 1994 All All Koibuchi, 1998Kuroishi, 1992Greenwald, 1978Owen, 1985Ogawa, 1987Tamburini, 1981Feldman, 1981Smith, 1985Smith, 1980 Cancer found by BSE vs found by chance 0.60 (0.46 −0.80) 0.66 (0.44 −1.01) Figure 2 Observational studies of women with breast cancer, comparing the rates of advanced breast cancer between the BSE and non-BSE groups. A test for heterogeneity between the studies yielded a P-value of o0.001 for those studies based on women who practise BSE and a P-value of 0.051 for those based on finding cancer by BSE.…”

“…Italics indicate that the data were estimated from results presented in the paper. If the study in which some women had mammography (Huguley et al, 1988) is excluded, the estimate is not substantially different (relative risk 0.69, 95% CI 0.56 -0.85, Po0.001). In those women who reported that their cancer was detected during self-examination, there was no evidence of a reduction in the risk of death compared to those who found their cancer by chance (relative risk 0.90, 95% CI 0.72 -1.12, P ¼ 0.34).…”

“…Studies on women newly diagnosed with breast cancer A total of 15 studies were based only on women newly diagnosed with breast cancer (Greenwald et al, 1978;Smith et al, 1980;Feldman et al, 1981;Tamburini et al, 1981;Foster and Costanza, 1984;Owen et al, 1985;Smith and Burns, 1985;Ogawa et al, 1987;Huguley et al, 1988;Kuroishi et al, 1992;Le Geyte et al, 1992;Kurebayashi et al, 1994;Auvinen et al, 1996;McPherson et al, 1997;Koibuchi et al, 1998) and they were divided into four groups based on two different measures of outcome and two different measures of exposure.…”

“…In one study (Koibuchi et al, 1998), all women had a clinical examination as part of a massscreening programme. A difference between the BSE and non-BSE group was reported with respect to mammography use in one study (18% in the BSE group compared to 7% in the non-BSE group, Huguley et al, 1988) and mass screening by clinician examination in another study (37% in the BSE group and 21% in the non-BSE group, Kuroishi et al, 1992); analyses were performed both with and without these two studies.…”