I just had an extraordinary experience with kappa and lambda light chain staining, or rather the lack thereof. I didn't get to see the IHC slides, which were prepared at a reference laboratory (well, to give them due credit, by Vanderbilt's hematopathology division).
I saw an odd-looking lymphoma in an older woman, and sent the material to Vanderbilt for immunostains. (Unfortunately I could not prepare imprints or obtain flow cytometry, since I received the specimen already in formalin.) Vandy did the necessary immunostains, and could not see either kappa and lambda marking. IHC for IgG heavy chain was however positive. Cells showing plasmacytoid differentiation marked for CD138, while more lymphocyte-like tumor cells marked for CD20 and other B-cell markers. Their diagnosis of gamma heavy chain disease was borne out by subsequent serum protein studies (I haven't seen those reports.) Apparently they tumbled to the diagnosis because of the lack of light chain marking in a tumor that seemed obviously clonal. Impressive! (Furthermore, Vandy's favored to kick UT's butt a week from Saturday.) Bob Richmond Samurai Pathologist Knoxville TN _______________________________________________ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet