Clinical algorithm to predict who may benefit from CDK4/6 inhibitors in patients (p) with estrogen receptor positive and HER-2 negative (ER+/Her2-) metastatic breast cancer (MBC).

e13060Background: Sequential endocrine therapy is the usual practice strategy for p with ER+/Her2- MBC. Last years, cyclin-dependent kinases 4 and 6 (CDK4/6) inhibitors may change the gold standard of treatment in first line. The increase of cost to treat all the p with CDK4/6 inhibitors could be an important effort for public institutions. Furthermore, any clinical trial has showed evidence of overall survival (OS) benefit in front of endocrine therapy. We hypothesize which p may have good response to the sequential endocrine therapy. Methods: We perform a retrospective analysis of 179 p with ER+/HER2- MBC visited in medical oncology service in our centre (ICO-Badalona) from 2004 to 2014, treated with hormonal therapy. Males were excluded. We categorized different group p, such as age at diagnosis (per decades), metastatic side affected at metastatic diagnosis (3 groups: only bone, bone plus other and visceral) and time to relieve (4 groups: de novo, less than 2 years with hormonal adjuvant treatment, fr...