Impact of different baking times on immunohistochemical staining of paraffin tissues in breast cancer with HER2 low expression
HE Chunhui
YANG Yi
FU Jiaju
SI MA Yawei
GAO Pingyu
Abstract：Objective: To investigate the effect of different baking times on the immunohistochemical staining results of HER2 low expression in breast cancer paraffin-embedded tissues, and to explore the most suitable baking time for HER2 low expression immunohistochemical staining. Methods: A total of 55 breast cancer tissue specimens with previously confirmed HER2 low expression were collected, including 40 cases of HER2 1+ and 15 cases of HER2 2+ without FISH amplification. After baking for different durations (15 min, 30 min, 1 h, 2 h, 6 h, and 12 h), each specimen was subjected to HER2 immunohistochemical staining on the same platform. The results were interpreted by three experienced pathologists using a double-blind method. Results: In the groups baked for 15 min, 30 min, 1 h, and 2 h, the nuclear membrane staining was clear, with obvious contrast, and cell counting was easier. However, in the groups baked for 6 h and 12 h, it was difficult to interpret under the microscope. The consistency of the interpretation results for baking times ranging from 15 min to 12 h was 100%, 100%, 98.1%, 96.3%, 76.3%, and 58.1%, respectively. Conclusion: For the detection of HER2 low expression in breast cancer paraffin-embedded tissues, baking at 75°C for 15 min or 30 min with a flat method yields high consistency in staining results and is worth promoting.
Keywords：BakingTimeHER2ImmunohistochemistryBreast Cancer
Publication Date：2025-11-28
Online Publishing Date：2025-12-04(First online date of this platform, not the publication date of the document)
Pages：4( 1511-1514 )