Diagnostic utility of the germinal center-associated markers GCET1
, HGAL, and LMO2 in hematolymphoid neoplasms.
Recently, new germinal center (GC)-associated markers, such as GCET1, HGAL, and LMO2, have been introduced.
By adding GCET1 and FOXP1, Choi et al (66) increased the concordance of immunohistochemical classification of GC versus non-GC to 93%, as compared with gene expression profiling.
Other systems use combinations of other markers ([Choi et al (45): GCET1, MUM1, CD10, BCL6, FOXP1], [Muris et al (48): BCL2, CD10, MUM1], [Natkunam et al (49): LMO2], [Nyman et al (50): MUM1, FOXP1], and [Meyer et al (51): CD10, GCET1, MUM1, FOXP1, LMO2]) to achieve a more accurate prediction of the gene expression profile results (Figure 3, a through n).
The BL cells consistently express germinal center-associated markers including BCL6, GCET1, and HGAL.
It may also be of benefit to add staining for GCET1, FOXP1, and LMO2 for more accurate cell-of-origin determination using the Tally classifier.
Other commonly used immunohistochemical cell-of-origin classification schemes include the algorithm by Choi et al (57) (Figure, B), in which 2 to 4 immunohistochemical stains are evaluated (including GCET1
, MUM1, CD10, BCL6, and FOXP1), and a tally algorithm56 (Figure, C), which uses 4 to 5 immunohistochemical stains (including CD10, GCET1
, MUM1, FOXP1, and LMO2).
Other markers, including BCL6, human germinal center-associated lymphoma (HGAL also known as GCET2) antigen, (50) or GCET1
, may be used as alternatives.
Immunohistochemistry of GCET1 shows a granular cytoplasmic stain pattern.
Gcet1 (centerin), a highly restricted marker for a subset of germinal center-derived lymphomas.