Application Of Immunohistochemical Staining In The Assessment Of Cutaneous Melanoma Breslow Thickness

Objective: HE staining is currently the most classic and commonly used method to measure Breslow thickness in cutaneous malignant melanoma.Because melanoma presents a variety of cellular morphological features and histological growth patterns,it is sometimes difficult to assess the exact depth of melanoma based on HE staining alone,and immunohistochemical staining has become an important technique to assist in the diagnosis of melanoma and measurement of tumor thickness.In this study,we sought the best staining markers for immunohistochemical staining to improve the accuracy of measurement and also to measure the Breslow thickness of malignant melanoma.Methods: Pathological sections clearly diagnosed as cutaneous malignant melanoma in the Department of Dermatology of the First Affiliated Hospital of Xinjiang Medical University from February 2017 to September 2022 and examined by HE staining and immunohistochemical staining in the Department of Pathology of the First Affiliated Hospital of Xinjiang Medical University were selected and screened using SOX-10,S-100,HMB-45,Melan-A,Ki-67 and other indicators to perform Immunohistochemical sections were selected.The above sections were re-read,and the Breslow thickness measured under different sections was measured and recorded.Results: Our study included 38 cases involving adjacent tissue HE-stained sections(38 cases),including 30 cases of invasive melanoma and 8 cases of melanoma in situ,as well as serial sections of S-100(37 cases),Melan-A(38 cases),HMB-45(38 cases),SOX-10(5 cases),and Ki-67(37 cases).Statistical differences in Breslow thickness were found in HE and S-100 and HE and Melan-A stained sections(P ? 0.05),while no statistical differences in tumor thickness were assessed in HE and HMB45 stained sections.In Melan-A stained sections,Breslow thickness was found to be greater in 18 sections and in S-100 stained sections,15 sections were found to possess greater tumor thickness.Conclusion:In some cases,HE staining does not reveal the actual size of melanoma invasion,in which case immunohistochemistry can be used as a complementary method.Among melanoma-related immunomarkers,the combination of S-100 and Melan-A staining helps to accurately diagnose melanoma in situ and measure the depth of invasive tumors.