Is there any concordance between of IHC with FISH in HER2-positive breast cancer patients?

Background: in developed or developing countries,the most common cancer in women is breast cancer with a pick in 40-50 years in asia. herein,we compared the association between ihc with fish in her2-positive breast cancer patients and affection of trastuzumab on disease free survival and overall survival (os). subjects and methods: immunohistochemical (ihc) analysis of hormone receptors and her2 was performed in 133 patients with breast cancer between 2003 and 2014. patients were selected for herceptin adjuvant treatment,according to ihc 3+ or fish+. the specimens for pathology reports were fixed at 10% neutral-buffered formalin (ph=7.4) for 24 hours,then sliced into 4 µm sections. results: the mean age of patients at diagnosis was 46.39 years (range,24-78 years),100% female. concordance rates between ihc and fish were 31.1% for ihc 2+ and 84.1% for ihc 3+ (p<0.001). the 87 patients had age ≤50 years and 46 patients had >50 years. of the 133 patients,30 patients (22.6%) had metastasis and 72 (54.1%) had right involvement. ninety three (69.9%) patients had lymph node invasion. 48 patients (36.1%) were treated with trastuzumab and 85 (63.9%) were treated without trsastuzumab. the 10-year survival rate was 70% and the mean survival was 49 months. conclusions: we recommend clinicians that fish analysis is as a predictor in breast cancer patients with ihc score 2+. in contrast,fish analysis of ihc 3+ samples was no useful. trastuzumab therapy is effective and tolerated for breast cancer with ihc 3+ and probably ihc 2+/fish+. © 2017,tehran university of medical sciences (tums). all rights reserved.