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A nonsteroidal drug, C17H11N5, that inhibits the enzyme aromatase and is used to treat breast cancer in postmenopausal women.

[le-, of unknown origin + alteration of triazole.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Pharmacology) an anti-oestrogen drug used in the treatment of breast cancer in post-menopausal women. Also called (trademark): Femara
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
References in periodicals archive ?
To our knowledge, there is only one study that an aromatase inhibitor, Letrozole plus rFSH was used for ovarian stimulation.4 In the presented case series, we have shown that COH can be started at any time in a menstrual cycle in the case of emergency fertility preservation.
(1) There are three available AIs: anastrozole, letrozole, and exemestane.
Letrozole is one such oral nonsteroidal aromatase inhibitor which prevents the aromatase from producing estrogens by competitive, reversible binding to the heme of its cytochrome P450 unit [2, 3].
Six months of vitamin D at 30,000 IU per week proved safe and was associated with "less worsening" of musculoskeletal events and fewer overall adverse quality of life events in women starting adjuvant letrozole (Femara) for hormone receptor--positive breast cancer, Dr.
All of the participants had received the aromatase inhibitors letrozole or anastrozole, nearly half had received tamoxifen, and two-thirds had received chemotherapy.
NEW drug letrozole cut the risk of breast cancer returning by one-fifth.
The FDA approved lapatinib in combination with letrozole for the treatment of postmenopausal women with advanced breast cancer that is hormone receptor and HER2 positive and for whom hormonal therapy is indicated.
In the EGF30008 trial, a double-blind, placebo-controlled, first-line Phase III trial to explore the benefit of letrozole with or without lapatinib, 1286 patients were randomly assigned to receive oncedaily treatment with letrozole plus lapatinib or letrozole plus placebo.
The treatment, known as Letrozole hormone therapy, cuts the supply of the hormone oestrogen which is needed for certain cancers to grow.
Letrozole versus testosterone: a single-center pilot study of HIV-infected men who have sex with men on highly active anti-retroviral therapy (HAART) with hypoactive sexual desire disorder and raised estradiol levels
The greatest benefit was with the newest aromatase inhibitors, such as letrozole (Femara) and anastrazole (Arimidex).