Cytochemical Cell Typing of Metastatic Tumors According to their Cytoskeletal Proteins

Conventional staining methods alone are often insufficient to make accurate histodiagnosis of malignant tumors. However, additional information about the cell type and the state of differentiation of tumor cells can be provided by several molecular markers. To be relevant diagnostically, these markers must be conservative, i.e. expressed not only in well differentiated tumors but also in poorly differentiated tumors and in metastases. These criteria are fulfilled by certain components of the cytoskeleton, notably the proteins forming the intermediate-sized filaments (IFs) and the desmosomal plaque proteins.