Immunohistochemistry (IHC) has been suggested to improve CE diagnosis by identifying plasma cells exhibiting expression of syndecan-1 (CD138, a marker of the plasma cell membrane), which is a heparan sulfate proteoglycan involved in inflammation (Bayer-Garner & Korourian 2001, Bayer-Garner et al. 2004). The gene discussed is SDC1; the disease is cholesteryl ester measurement.