The term "lymphoma" was originally used by Billroth in 1871 [55], and by Virehow [763] some years before that, for the designation of swelling of lymph nodes that was not due to "eareinoma, sareoma, ehondroma, myxoma, ete. " In his paper, Billroth reeounted sueeessful treatment with arsenie (" Fowler's solution") of multiple "lymphomas" that had developed in a 40-year-old woman during a 10-month period. From this report it is not entirely clear if the multiple" lymphomas" deseribed were infeetious or if they were eonsis- te nt with what we now mean by "malignant lymphoma. " Today, the term "malignant lymphoma" is generally used eolleetively for malignant lymphoproliferative neoplasms that tend to arise in lymph nodes and also eneompasses Hodgkin's disease and non-Hodgkin's lymphomas. The adjeetive "malignant" seems somewhat superfluous sinee, in addition to Bill- roth's original eonnotation, the sense of malignaney is nowadays read into the word "lymphoma. " To be sure, true, i. e. , malignant, lymphomas have to be differentiated from "pseudolymphomas," or to put it more exaetly, "pseudomalignant lymphomas. " In this book, "lymphoma" and "malignant lymphoma" are used interehan- geably for malignant neoplastie lymphoproliferative disorders, and "pseudo- lymphoma" is used for benign lymphomatous proeesses. Our editorial eonsultant, Dr. M. Leider, disagrees with all of this. In his Dictionary of Dermatological Words, Terms, and Phrases [421] and other works, he maintains that there is no etymologieal basis for words bearing the eontrived suffix" -oma" or the true Greek suffix" -ma" to denote malignaney.