CD30 is a 120 kDa transmembrane glycoprotein belonging to the tumor necrosis factor/nerve growth factor receptor superfamily.53 As well as being a classic marker for malignant cells of Hodgkin's lymphoma, CD30 has been recently implied in the regulation of the balance between Th1 and Th2 responses and the generation of T-cell memory.54, 55 A soluble form of CD30 (sCD30) of 85 kDa is cleaved in the bloodstream from the surface of activated T cells56 and its serum concentrations may be used as a functional marker for T-cell responsiveness. This evidence concerns the gene TNFRSF8 and Hodgkins lymphoma.