When Is Immunohistochemistry Useful in Assessing Tumor Necrotic Tissue?

Background/Aim: Immunohistochemistry (IHC) enables visualisation of the distribution of specific proteins, the differentiation of benign and malignant tumours, and the site and origin of a primary tumour. Surgical pathologists commonly examine tumours with extensive necrosis or non-viable tissue that may affect an accurate diagnosis. Materials and Methods: We investigated the sensitivity and specificity of IHC on necrotic samples derived from adenocarcinoma, squamous cell carcinoma (SCC) and melanoma using different markers. Results: Analysis of necrosis within tumours revealed 88% sensitivity and 56% specificity for melanoma, 95% and 92% for CK5/6, 95% and 83% for CK20, 37% and 95% for p63, 69% and 97% for Melan A, 88% and 92% for SOX-10, 98% and 56% for CKAE/AE3 and 75% specificity for CK7. Conclusion: Antibodies should be considered reliable markers for demonstrating the epithelial nature of a suspected tumour. Immunohistochemistry of necrotic tissues may provide clinically useful information.