[Letrozole vs. tamoxifen as neoadjuvant therapy for postmenopausal patients with hormone-dependent locally-advanced breast cancer].
Author(s): Novoa Vargas A, Font Lopez KC, Amador DD
Affiliation(s): Hospital General de Zona 57, IMSS.
Publication date & source: 2011-09, Ginecol Obstet Mex., 79(9):553-7.
Publication type: Comparative Study; English Abstract; Randomized Controlled Trial
BACKGROUND: Previous studies demonstrated that Letrozole (aromatase inhibitor) and tamoxifen (selective modulator of estrogen receptors) are effective in the treatment of postmenopausal women with locally advanced tumors, stage III and hormone dependent. OBJECTIVE: To present display the complete clinical answer incidence and the complete pathological answer with the use of induction hormonotherapy. METHODS: Put-analysis in 40 patients with breast cancer, to chanalicular infiltrated, eligible were treated in a prospective study, to double blind person, using per os: letrozol, 2.5 mg; tamoxifen, 20 mg, known widely like selective modulator of estrogen receivers; oral route, during 36 consecutive months. Reports at the beginning were taken, subsequent to 3, 6 and 12 months to evaluate the frequency of complete respond. The patients, who did not show answer neoadjuvant therapy, were put under treatment with radiotherapy. The patients who showed good partial pathological respond, or clinical partial respond, went candidates to radical mastectomy. According to the protocol of the study, the patients subsequent to surgery who showed partial pathological respond or complete pathological respond, continued adjuvant handling adyuvant therapy by 2 years consecutive or until the presence of progression of the disease. It was used like statistical method Chi2, with p of Table cloth to evaluate the differences. RESULTS: During a period of 3 years, january of the 2003 to january of the 2005, 2 groups of patients, 40 studied altogether; the age average was of 65,5 years, with a rank of 55 to 75 years with breast cancer, stages: IIA to IIIB. Without complete respond 25% of the group with tamoxifen; 20% with letrozol Those patients happened to radiotherapy. The collateral effects of the use of hormonotherapy with letrozol appeared in a 55% and with the use of tamoxifen in a 60% of the patients with breast cancer (p = 0.5). They did not respond to neoadyuvant therapy (hormonal receptors < to 30%): with letrozol 19% of them and 25% with tamoxifen; reason why they received treatment with radiotherapy. All patients candidates to surgery, were benefitted with the mastectomy handling. CONCLUSIONS: Results although preliminary, suggest that neoadyuvant treatment with hormone-therapy in postmenopausal patients with breast cancer, have good prognosis. Induction therapy, were better tolerated, with greater effectiveness and improved the clinical and objective respond in women with breast cancer in the postmenopausal. Work serves as tool to determine the indication to us of induction hormonotherapy; and identify to those patients with breast cancer, locally advanced in post menopause with better prognosis to be rescued with radical mastectomy. Study needs more background and show the impact of letrozol, as hormonotherapy used in neoadjuvancy, to confirm if relieves period without disease or survives, before mastectomy. In a near future, it shall important to investigate if is useful the radical mastectomy in those postmenopausal patients with complete objective respond, after the use of an aromatase inhibitor.