For the Differentiation and Characterization of Malignant Tumors

Antibodies are used to help differentiate and characterize neoplastic tumors that have been deemed malignant by H&E staining. Since poorly differentiated tumors could represent one of many cancers, several or more antibodies are usually used as a primary screening panel to help identify a particular group of cancer (e.g., carcinoma or sarcoma). Further antibody studies can help identify the specific kind of cancer (e.g., mantle cell lymphoma). The abbreviated algorithm shown above is similar to many in use, however, no one algorithm has been universally accepted, and each lab should determine which antibodies to use and how to interpret the results. The indicated antibody results shown above are typically for the type of cancer indicated, but every tumor is different and can show unique expression of various markers; very few tumor markers are expressed in every tumor of a particular type of cancer, and very few tumor markers are expressed exclusively in only one type of cancer.