Aromatase inhibitors versus tamoxifen for management of postmenopausal breast cancer in the advanced disease and neoadjuvant settings.
The third-generation aromatase inhibitors anastrozole, exemestane and letrozole have become firmly established as the agents of choice in patients with tamoxifen-resistant tumors. Large, well-conducted, double-blind clinical trials directly comparing the non-steroidal aromatase inhibitors anastrozole and letrozole with tamoxifen in the advanced disease setting have matured. Based on these trials, there is sufficient evidence to choose one of these agents over tamoxifen because of a superior time to disease progression and acceptable toxicity which includes a lower incidence of thromboembolic complications. Information for the steroidal aromatase inhibitor exemestane will be forthcoming from a phase III trial which has completed accrual. Consistent with the findings in the advanced disease setting, a double-blind trial comparing letrozole with tamoxifen in the neoadjuvant setting revealed superiority for letrozole in terms of clinical response rate. This provides a strong impetus for further study of the aromatase inhibitors in the preoperative setting.
Ingle
James N
JN
Division of Medical Oncology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA. ingle.james@mayo.edu
Suman
Vera J
VJ
D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use; D047072:Aromatase Inhibitors; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000473:pathology; D017326:Clinical Trials, Phase III as Topic; D004791:Enzyme Inhibitors / Q000494:pharmacology / Q000627:therapeutic use*; D004965:Estrogen Antagonists / Q000627:therapeutic use*; D006801:Humans; D020360:Neoadjuvant Therapy; D017698:Postmenopause; D016032:Randomized Controlled Trials as Topic; D013629:Tamoxifen / Q000627:therapeutic use*
D018931:Antineoplastic Agents, Hormonal; D047072:Aromatase Inhibitors; D004791:Enzyme Inhibitors; D004965:Estrogen Antagonists; D013629:Tamoxifen