Publication Year: 2000 Visited: 141

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A Metanalysis of the Interaction Between Her2 and the Response to Endocrine Therapy (ET) in Metastatic Breast Cancer (MBC). Michele De Laurentiis, Grazia Arpino, Erminia Massarelli, Chiara Carlomagno, Fortunato Ciardiello, Giampaolo Tortora, Angelo R Bianco, Sabino De Placido, Università Fedelico II, Napoli, Italy; Università Fed II, Napoli, Italy.

HER2 is a protooncogene that encodes for a tyrosine-kinase cell membrane receptor. Experimental data suggest a complex cross-talk between the Her2 and the estrogen receptor (ER) pathways and it has been speculated that HER2 overexpression may be a marker of breast cancer resistance to ET. Several authors have analyzed series of MBC patients (pts) treated with ET to identify a correlation between the response rate (RR) and HER2 status. However, a consensus has yet to be reached. We have reviewed all the pertinent published data and have made a metanalysis. Studies have been identified by an extensive search of Medline and Embase. Selection criteria were: a) MBC pts treated with ET c)RR assessed according to HER2 status. For each study the odds of disease progression was taken as an indicator of the tumor resistance to the treatment and the odds ratio (OR) for HER2+ over HER2- patients with 95% confidence interval (95%CI) was calculated as an estimate of the predictive effect of HER2. An overall estimate of the OR was computed by the Mantell-Haenszel method. Seven studies were included in the metanalysis (1110 pts). The overall OR was 2.46 (95%CI=1.81-3.34). [Table] These results indicate that MBCs overexpressing HER2 are resistant to ET.