Researchers from Italy have reported that patients with relapsed or refractory extranodal marginal-zone lymphoma have a high response rate following treatment with Zevalin® (90Yttrium-ibritumomab tiuxetan). The details of this study were presented at the Joint ECCO 15 – 34th ESMO Multidisciplinary Congress in Berlin, September 20-24, 2009.
Marginal zone lymphomas are a relatively uncommon type of B-cell non-Hodgkin’s lymphoma (NHL), comprising approximately 2-4% of all cases. There are about 61,000 new cases of NHL diagnosed annually, of which 1,000-2,000 are marginal zone. Some of these marginal zone lymphomas are in extranodal sites including the spleen (splenic marginal lymphomas). Marginal zone lymphomas also fall into the category of mucosal associated lymphoid tissue (MALT lymphomas). MALT lymphomas are frequently associated with gastric Helicobacter Pylori infection. Marginal-zone lymphomas are included in the “low grade” category, and treatments are similar to patients with chronic lymphocytic leukemia (CLL) and follicular lymphoma. This generally means Rituxan® (rituximab)-based therapy.
Zevalin is a radioimmunotherapeutic agent currently approved in the United States for the treatment of patients with relapsed or refractory, low-grade, or follicular B-cell NHL, including those refractory to Rituxan® (rituximab). Zevalin is also indicated, under accelerated approval, for the treatment of relapsed or refractory, Rituxan-naive, low-grade and follicular NHL.
The current study involved 24 patients with relapsed or refractory marginal-zone lymphoma that was present in extranodal sites and treated with Zevalin between 2004 and 2009. Ten of the 24 cases had Helicobacter Pylori-negative gastric MALT NHL, and 14 had extra-gastric marginal-zone lymphoma. Twenty-one of these 24 patients had disseminated disease. Twenty-one patients were evaluable for response, and the median follow-up was 22 months:
- 76% had a complete response.
- Duration of remission was three to 59 months, with six of 16 patients remaining in remission for greater than three years.
- Survival was 100%.
Comments: These and other studies suggest that Zevalin is one of the most effective agents available for the treatment of B-cell NHL of any type, but especially low-grade NHL.