Biclonal component in lymphoplasmacytic/lymphoplasmacytoid non-Hodgkin lymphoma.

We report a case of biclonal component in lymphoplasmacytic/lymphoplasmacytoid non-Hodgkin's lymphoma, in which two Ig with different light chains were found, because not many cases have been reported. In our case in conjunction with the presence of an IgM-K protein, which was in accordance to both cytomorphologic aspects similar to WM and monoclonal population (K), another protein that showed different light chain was expressed (IgG-lambda). Therefore it is possible that in a neoplastic clone a subsequent neoplastic change could verify, not closely related to the first, and subsequently the presence of a subclone with the possibility to rearrange for a new protein with light chain different from the first protein. Demonstration of the isotypic difference in case of lymphoid malignancies is of critical importance in developing therapeutic protocols involving use of anti-idiotype antibodies.