Table 2

Useful immunohistochemical stains

Specificity of monoclonal antibody (or polyclonal antiserum)Condition or circumstance in which immunohistochemical stain is useful
MGUS, monoclonal gammopathy of undetermined significance.
CD3, CD1a, CD5, CD8Detection of T cells and T cell subsets (note: CD5 is also expressed on some B cells and B cell neoplasms and CD1a on Langherhan's cells)
CD20, CD79a, CD10, CD23Detection of B cells and B cell subsets
Terminal deoxynucleotidyl transferase (TdT)Detection of immature cells in most acute lymphoblastic and some acute myeloid leukaemias
CD34Detection of immature cells in acute and chronic leukaemias and some cases of myelodysplastic syndrome (also useful for accentuation of vessels)
Myeloperoxidase, neutrophil elastase, CD68Detection of granulocytic and monocytic differentiation
GlycophorinDetection of erythroid cells
CD61 or von Willebrand's factorDetection of megakaryocytes
Light chains (κ or λ)Detection of isotype restriction (and therefore probably monoclonality) in multiple myeloma, MGUS, lymphoplasmacytoid lymphoma, and amyloidosis
CD15Confirmation of Reed-Sternberg and mononuclear Hodgkin's cells
CD30Detection of infiltration by anaplastic large cell lymphoma and Reed-Sternberg and mononuclear Hodgkin's cells
CD31Endothelial cells (macrophages, monocytes, megakaryocytes, and plasma cells are also positive)
Cyclin D1Detection of mantle cell lymphoma
ALK1Detection of anaplastic large cell lymphoma
Epithelial membrane antigenDetection of infiltration by carcinoma cells or anaplastic large cell lymphoma
Cytokeratin, prostate specific antigen, prostatic acid phosphataseDiagnosis of infiltration by carcinoma cells
CD1aDiagnosis of Langherhan's cell histiocytosis
Mast cell tryptaseDetection of mast cells and diagnosis of systemic mastocytosis
HMB45 and melan A (S100 less specific)Melanoma
Vimentin, desmin, actin, myoglobin, chromogranin A, protein gene product 9.5, neurone specific enolaseDifferential diagnosis of small cell tumours of childhood