Intralesional rituximab for cutaneous B-cell lymphoma.

Rituximab, a chimeric anti-CD20 monoclonal antibody, has been approved for systemic treatment of relapsed or refractory CD20-positive B-cell non-Hodgkin's lymphoma. As cutaneous B-cell lymphoma (CBCL) also expresses the CD20 molecule, three patients with histologically and immunohistochemically confirmed CBCL without systemic involvement were treated with low-dose intralesional rituximab in a pilot study. Single doses applied ranged from 10 to 30 mg per lesion, according to lesion extent, with a cumulative dose of up to 350 mg. Injections were given two or three times weekly for 3-5 weeks, with a second cycle after 6 weeks in one patient with incomplete remission. Complete and lasting remission was achieved in each patient; this has persisted for up to more than 1 year. The observed adverse events were of grade 1 severity. Results suggest that intralesional rituximab may be a safe and effective new therapy modality for CBCL.