HER2 gene amplification in breast cancer by fluorescence in-situ hybridization and its clinicopathologic relationship / 临床与实验病理学杂志

ABSTRACT

Purpose To detect the HER2 gene amplification by fluorescence in-situ hybridization(FISH) and to explore its clinicopathologic relationship with the breast cancer.Methods A prospective study was conducted in 50 cases of breast invasive ductal carcinoma from Beijing Toren Hospital. Clinicopathologic data were summarized and FISH was performed in the paraffin-embedded sections for HER2 gene amplificayion using DNA probe, and immunohistochemical stain for ER, PR and HER2.Results The average age of the patients was 55.5 years. The pathologic grading showed that 11 cases were in grade Ⅰ, 30 cases in grade Ⅱ, and 9 cases in grade Ⅲ. The TNM staging showed that 13 cases were in stage Ⅰ,15 cases in ⅡA,13 cases in ⅡB,6 cases in ⅢA,2 cases in ⅢB,and 1 case in ⅢC.The median metastasis rate of lymph node was 6.91%.33 cases were positive for ER,and 32 cases positive for PR.For HER2 detection, 40 cases were positive by IHC and 33 positive by FISH. HER2 gene amplification by FISH was closely related with the expression of HER2 protein by immunohistochemistry, but not significantly related with pathologic grading, The TNM staging, median lymph node metastasis rate, ER and PR status (P>0.05). FISH test was positive in 3 cases of tumor embolus and 3 cases of multiple primary tumors. Conclusions FISH and immunohistochemistry for detecting HER2 have a good conformance, HER2 gene amplification may be related with tumor embolus and multiple primary tumors, but it can not be used as an indirect marker to predict the prognosis.