Abstract
For patient with breast cancer estrogen receptor positive, the adjuvant and neoadjuvant endocrine therapy has an absolute benefit. The metastatic stage includes a diverse group of tumors that vary according to the site of metastasis, time of appear, general condition of the patients, and other intrinsic characteristics of the tumor. survival in cancer varies according these features, from a few months to many years. Estrogen hormones stimulate nuclear and cytoplasmic receptors. In neoplastic cells, estrogen regulate RNA transcription, with persistence of proliferation. The blocking of hormonal action in metastatic cancer, has resistance mechanisms with the use of parallel signaling pathways, this knowledge has allowed the development of inhibitors of CDK 4/6, mTOR and PIK3-CA, which are recommended in metastatic disease. with significant prolongation of overall survival. In visceral crisis, the use of sequential or combined systemic chemotherapy is still maintained.
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Copyright (c) 2020 Evelyn Valencia Espinoza