Predictive factors for response to rituximab in Waldenstrom's macroglobulinemia.
Rituximab is an active agent for the treatment of Waldenstrom's macroglobulinemia. However, many patients do not respond to this agent and several others develop secondary resistance. In order to identify clinical and laboratory parameters that could predict a higher likelihood for response, we evaluated 54 patients who were treated with single-agent rituximab. Twenty-four patients (44%)exhibited > or = 50% reduction of serum monoclonal protein. Previously untreated and pretreated patients had the same probability for response. Low response rates were noted in patients with serum monoclonal protein level > or = 40 g/L (17%) and serum albumin level < 35 g/L (14%). Furthermore, a multivariate analysis indicated that high serum monoclonal protein and low albumin were the dominant variables associated with shorter time to progression. The presence of 2, 1, or none of these variables was associated with median times to progression of 4 months, 11 months, and approximately 48 months, respectively. We conclude that patients with low levels of monoclonal protein and normal albumin are the best candidates for treatment with rituximab.
Dimopoulos
Meletios A
MA
Department of Clinical Therapeutics, University of Athens School of Medicine, 227 Kifissias Avenue, Kifissia, Athens 14561, Greece. mdimop@med.uoa.gr
Anagnostopoulos
Athanasios
A
Zervas
Constantinos
C
Kyrtsonis
Marie C
MC
Zomas
Athanasios
A
Bourantas
Constantinos
C
Anagnostopoulos
Nicolaos
N
Pangalis
Gerrassimos
G
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal / Q000494:pharmacology* / Q000627:therapeutic use*; D058846:Antibodies, Monoclonal, Murine-Derived; D000970:Antineoplastic Agents / Q000494:pharmacology* / Q000627:therapeutic use*; D018450:Disease Progression; D019008:Drug Resistance, Neoplasm; D005260:Female; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D007147:Immunoglobulin Light Chains / Q000032:analysis; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D000069283:Rituximab; D012709:Serum Albumin / Q000032:analysis; D016896:Treatment Outcome; D008258:Waldenstrom Macroglobulinemia / Q000188:drug therapy* / Q000473:pathology
D000911:Antibodies, Monoclonal; D058846:Antibodies, Monoclonal, Murine-Derived; D000970:Antineoplastic Agents; D006454:Hemoglobins; D007147:Immunoglobulin Light Chains; D012709:Serum Albumin; D000069283:Rituximab