Application of environment-friendly tissue sample release agent in HER2 gene detection of HER2 IHC 2+invasive primary breast cancer

SHAN Jian; DONG Sijia; DENG Jialu; LI Xin; LIN Ziqin; MI Xianjun; WANG Dewang

doi:10.3969/j.issn.1007-8096.2025.10.009

Abstract：Objective To explore the application value of environment-friendly tissue sample release agent in human epidermal growth factor receptor 2(HER2)gene detection of invasive primary breast cancer(IPBC)with uncertain expression of HER2 protein.Methods A total of 619 IPBC specimens were randomly selected as research subjects.After fixation and sectioning,two pieces of lesional tissue were randomly taken from each specimen and assigned to a control group and an observation group,respectively.The control group was treated with traditional reagents(formaldehyde fixation-ethanol dehydration-xylene clearing and dewaxing),while the observation group was treated with the environmentally friendly tissue sample release agent,and paraffin sections were prepared for both groups.Immunohistochemical(IHC)staining was used to detect the expression of HER2 protein in the IPBC sections of the two groups.For the 202 IPBC specimens with HER2 IHC 2+,additional sections were made,and fluorescence in situ hybridization(FISH)was employed to detect the HER2 gene amplification.The differences and concordance rates of HER2 protein expression and gene amplification between the two groups were compared.Results HER2 IHC staining in sections of both groups showed accurate localization,manifested as specific cell membrane staining.There was no statistically significant difference in HER2 IHC results(positive,indeterminate,negative)between paired sections of the two groups(P=0.73).For HER2 gene amplification in the sections of both groups,the HER2 and Ch17 signals in the specific cell nuclei were clear and easy to identify;the cell contours were distinct,nuclear morphology was intact,and the background was clean without spot artifacts.There was no statistically significant difference in the number of successfully detected cells by FISH between paired HER2 IHC 2+sections of the two groups(t=0.39,P=0.69).There was no statistically significant difference in the number of FISH detection signals between paired HER2 IHC2+sections of the two groups(P>0.05).There was no statistically significant difference in the positive rate of FISH detection between paired HER2 IHC 2+sections of the two groups(P=1.00).There was no statistically significant difference in the total positive rate of HER2 between sections of the two groups(χ2=0.04,P=0.84).Conclusion The use of environment-friendly tissue sample release agent can ensure the effectiveness of HER2 IHC and FISH detection for IPBC specimens,and has promising application prospects.