Evaluation of HER2 gene amplification status in invasiveudbreast cancer patients by Fluorescence in Situ Hybridizationudanalysis and its correlation with clinical features

摘要

Precise assessment of HER2 gene status as an important biomarker plays audsignificant role in identifying the eligible patients for Trastuzumab therapyudand determining their clinical outcomes. In this study, the researchersudassigned HER2 amplification status in invasive breast cancer specimens byudFluorescence in Situ Hybridization (FISH) and determined its associationudwith other clinical features. Formalin-fixed paraffin embedded tumor tissueudspecimens of 46 patients with invasive breast cancer were collected fromudNovember 2011 till May 2012. HER2status was evaluated by FISH. TheudZytolight SPEC HER2/CEN17 dual color probe kit was applied forudassessment of HER2status. HER2 gene amplification was defined asudHER2/CEP17 ratio>2.2.The association between HER2status and clinicaludfeatures like tumor grade, tumor type, tumor size, axillary lymph nodeudinvolvement and age of patient was done using Chi squared test at the 0.05udlevel of significance (p value). Amplification of HER2 gene was detectedudin twelve cases (26%). On statistical analysis HER2status showedudcorrelation with tumor grade (p=0.02).There was no correlation betweenudHER2status and tumor type, tumor size, lymph node status and age ofudpatients. The results of this study are consonant with the findings of otherudstudies about the presence of HER2 gene amplification in invasive breastudcancer. Statistical analysis showed patients with HER2 amplified geneudhave tumors with higher grade. In these patients the probability ofudincreased proliferation and metastasis is high therefore evaluation of HER2udgene amplification status in breast cancer patients specially in high gradeudtumor with an accurate method such as FISH is essential