Waldenstrom\'s macroglobulinemia (WM) is a malignant disorder of lymphoplasmacytic cells that produce a monoclonal immunoglobulin M (IgM). Since the original description by Jan Waldenström of three patients with symptoms of hyperviscosity due to circulating monoclonal IgM, the definition of WM has been controversial. Standardized criteria for diagnosis have now been proposed, including the presence of any IgM monoclonal protein and marrow and/or nodal lymphoplasmacytic cells. Although previous response criteria have generally incorporated parameters for monoclonal protein reduction and/or improvement of marrow/nodal involvement, specific and uniform response criteria are needed to facilitate comparisons of response, remission duration, progression-free survival, and overall survival in clinical trials similar to those previously established for other diseases such as chronic lymphocytic leukemia, lymphoma, and myeloma. This is of particular importance as new agents are developed and evaluated. This presentation represents
consensus recommendations for uniform response criteria for use in assessing responses to treatment for patients with WM, which were prepared in conjunction with the Second International Workshop held in Athens, Greece during September 2002.