ABSTRACT
Through carefully designed randomized trials for early stage breast cancer, breast-
conserving surgery followed by whole breast radiation therapy (RT) has been shown to
result in survival equivalent to that achieved with modified radical mastectomy while
affording a woman the opportunity to preserve her breast (1-6). However, in women with
hereditary breast cancer, outcomes following mastectomy versus breast-conserving
therapy have not been directly compared. Thus, comparability of rates of local control,
disease-specific survival, overall survival, and toxicity by treatment is unproven. In
addition, questions have been raised as to whether the baseline elevated breast cancer risk
in women with hereditary disease will be further increased due the use of radiotherapy to
the breast for treatment of the index cancer. Given the limited number of patients
diagnosed with hereditary breast cancer each year and the uncertainty whether these
women would consent to a randomization between mastectomy and breast conservation,
it is doubtful whether a randomized comparison will ever occur. Thus, our current
knowledge of ipsilateral breast tumor recurrence (IBTR) following the use of breast-
conserving surgery and RT and the risk of developing a contralateral breast cancer in
women with hereditary breast cancer is based upon single and multi-institutional
retrospective analyses and prospective nonrandomized studies, primarily in women who
are known carriers of a BRCA1/2 breast cancer susceptibility gene. The potential implications of a conservative approach and actual clinical results, with emphasis upon
women with a known deleterious BRCA1/2 mutation, will be presented in this chapter.