title: Aromatase inhibitors in early breast cancer treatment.
abstract: A recent National Institutes of Health consensus guideline recommends the general use of adjuvant hormonal therapy for the treatment of early breast cancer in postmenopausal women with estrogen receptor-positive tumors. Standard therapy has been 5 years of tamoxifen, but about 30% of those patients fail to survive 10 years, many as a consequence of tamoxifen resistance. Promising results with the third-generation aromatase inhibitors anastrozole, letrozole, and exemestane in first- and second-line treatment of metastatic breast cancer has prompted their evaluation as adjuvant therapy in patients progressing on tamoxifen or as alternative first-line treatment. Anastrozole has recently achieved significantly longer disease-free survival than tamoxifen in a first-line adjuvant therapy trial, and letrozole is being investigated in several large adjuvant trials. Aromatase inhibitors appear to be well tolerated for long-term adjuvant treatment. In the neoadjuvant setting, letrozole has been especially effective compared with tamoxifen in downstaging primary tumors in postmenopausal women, permitting significantly more breast-conserving surgery.
mesh_terms: D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D047072:Aromatase Inhibitors; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000378:metabolism; D017024:Chemotherapy, Adjuvant; D002986:Clinical Trials as Topic; D004791:Enzyme Inhibitors / Q000627:therapeutic use*; D004965:Estrogen Antagonists / Q000627:therapeutic use*; D006801:Humans; D020360:Neoadjuvant Therapy; D009376:Neoplasms, Hormone-Dependent / Q000188:drug therapy* / Q000378:metabolism; D018579:Patient Selection; D011960:Receptors, Estrogen / Q000378:metabolism; D013629:Tamoxifen / Q000627:therapeutic use
chemical_list: D018931:Antineoplastic Agents, Hormonal; D047072:Aromatase Inhibitors; D004791:Enzyme Inhibitors; D004965:Estrogen Antagonists; D011960:Receptors, Estrogen; D013629:Tamoxifen