IgM multiple myeloma: report of four cases and review of the literature.

The differential diagnosis between multiple myeloma (MM) and Waldenström's macroglobulinemia (WM) is generally well defined. Consistent with a diagnosis of MM is the presence of a non-IgM monoclonal gammopathy associated to multiple osteolytic lesions and plasma cell infiltration of the bone marrow. Characteristic of WM is the presence of an IgM monoclonal gammopathy associated to lymphoadenopathy, hepatosplenomegaly, anemia and hyperviscosity syndrome in the presence of a monoclonal lymphoplasmacytoid proliferation in the bone marrow. Nonetheless, few cases of IgM myeloma have been reported that display clinico-pathologic features intermediate between MM and WM. Here, this study describes four of 317 (1.2%) patients with an IgM monoclonal gammopathy in whom the morphologic and clinical features were consistent with a diagnosis of IgM myeloma.

Treatment of 72 newly diagnosed Waldenstrom macroglobulinemia cases with oral melphalan, cyclophosphamide, and prednisone: results and cost analysis.

BACKGROUND: Current treatment regimens for Waldenstrom macroglobulinemia (WM) are based on the use of oral alkylating agents. Recently, however, other more costly agents have been proposed for the treatment of WM. In the current study, the authors report on results obtained using oral melphalan, cyclophosphamide, and prednisone (MCP) to treat 72 patients with WM, and they compare these results (and the associated costs) with those observed using more aggressive protocols. METHODS: Between July 1973 and April 2002, the authors documented overexpression of the immunoglobulin M paraprotein in 317 consecutive patients. Of these, 100 had newly diagnosed WM, and the 72 who were symptomatic were treated using the MCP protocol. Response rate, overall survival (OS), response duration, freedom from progression (FFP), event-free survival (EFS) duration, toxicity, and cost per course in Euro and U.S. dollars were evaluated for patients receiving this regimen. RESULTS: Seventy-one of 72 patients (99%) were evaluable. Of these patients, 55 (77%) achieved a response; 7 others (10%) experienced disease stabilization, and the remaining 9 (13%) experienced disease progression. After a median follow-up of 72 months (range, 3-195 months), the median durations of EFS, FFP, response, and OS were 47, 55, 64, and 66 months, respectively. No World Health Organization Grade III or IV toxicities were observed, and side effects were limited to transient nausea, emesis, and mild neutropenia. The cost per course of the MCP regimen was $16, similar to that of standard protocols involving chlorambucil and much less than that of more aggressive protocols (price range, $91-11091) proposed for the treatment of WM. CONCLUSIONS: Like chlorambucil-based protocols, the MCP regimen is a cost-effective and safe option for the treatment of patients with WM. Furthermore, the results obtained do not appear to be inferior to those yielded by more expensive, aggressive, and toxic intravenous protocols.