Breast cancer is the most common cancer in pregnant and postpartum women, occurring in about 1 in 3,000 pregnant women. The average patient is between 32 to 38 years of age and, with many women choosing to delay childbearing, it is likely that the incidence of breast cancer during pregnancy will increase.
Breast cancer pathology is similar in age-matched pregnant and nonpregnant women. Hormone receptor assays are usually negative in pregnant breast cancer patients, but this may be the result...
Added text to state that it is controversial whether the optimal duration of adjuvant tamoxifen therapy in premenopausal women is 5 years or 10 years.
Added text to state that long-term follow-up of the Adjuvant Tamoxifen Longer Against Shorter (ATLAS) trial revealed that 10 years of tamoxifen reduced the risk of breast cancer recurrence, reduced breast cancer mortality, and reduced overall mortality (Level of evidence: 1iiA). Included text to list the risks of tamoxifen therapy after 10 years.
Added text to state that the cumulative risk of endometrial cancer during years 5 to 14 from breast cancer diagnosis was 3.1% for women who received 10 years of tamoxifen versus 1.6% for women who received 5 years of tamoxifen.
Added text to state that these trials raise important questions about the optimal duration of endocrine therapy. The long-term ATLAS data are really applicable for women who remain premenopausal after 5 years of tamoxifen therapy. Randomized clinical trial data support the use of aromatase inhibitors in postmenopausal women.
Added text to state that the mild androgen activity of exemestane prompted a randomized trial to evaluate whether exemestane might be preferable to anastrozole as upfront therapy for postmenopausal women who were diagnosed with hormone receptor-positive breast cancer (cited Goss et al. as reference 160 and level of evidence: IiiA). The NCIC CTG MA.27 (NCT00066573) trial randomly assigned 7,576 postmenopausal women to receive 5 years of anastrozole versus exemestane. Based on the results of this trial, no specific aromatase inhibitor is considered superior as upfront therapy for postmenopausal women with hormone receptor-positive breast cancer.
Stage IIIB, Inoperable IIIC, IV, Recurrent, and Metastatic Breast Cancer
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