WASHINGTON, DC. There are two major alternatives for the surgical treatment of breast cancer. One, mastectomy, involves removal of the entire involved breast while the other, breast conservation therapy (BCT), involves removing just the tumour (lumpectomy) and subsequent radiation therapy. If the lymph nodes in the armpits (axillary lymph nodes) are found to be affected they are usually removed as well.
Researchers at the National Cancer Institute undertook a study between 1979 and 1987 to evaluate the survival rate of women who had undergone mastectomy as compared to women who had been treated with BCT. The 237 study participants have now been followed up for a median of 18.4 years. The survival rate for mastectomy patients over this period was 58% versus 54% in the BCT group – a difference that was not statistically significant. The disease-free survival rate was 67% for the mastectomy group and 63% for the BCT group – again a difference that was not statistically significant. There was no statistically significant difference in the number of women who developed cancer in the previously unaffected breast (7 in the mastectomy group and 5 in the BCT group). There was also no difference in the number of women who developed cancer at sites other than the breast (10 in each group).
The researchers conclude that there are no statistically significant differences in the survival rate or in the
incidence of the development of new cancers between women treated with mastectomy and those treated
with breast conservation therapy.