Indolent primary cutaneous B-cell lymphoma: experience using systemic rituximab

Optimal treatment of indolent primary cutaneous B-cell lymphoma (CBCL), marginal zone lymphoma, and follicle center lymphoma, presenting as multiple lesions, has yet to be established. Rituximab is a chimeric monoclonal IgG1 antibody directed against the CD20 antigen of B cells. Clinical efficacy of systemic rituximab in CBCL has yet to be established.

We sought to assess the efficacy of systemic rituximab in the treatment of CBCL.

This was a retrospective study of 15 patients with indolent CBCL treated with intravenous rituximab (375 mg/m(2)) as a single agent. Variable maintenance regimen was used in a subset of patients. Responses were categorized as complete response, partial response, stable disease, or progressive disease. The efficacy end points included were objective response rate, time to response, time to progression, and duration of response.

Ten patients with follicle center lymphoma and 5 with marginal zone lymphoma were included. The objective response rate was 87% (60% complete response, 27% partial response). All patients with follicle center lymphoma had a response with 80% achieving complete response. Of the patients with marginal zone lymphoma, 3 had a response, one stable disease, and one progressive disease. Median follow-up was 36 months. Median time to response, duration of response, and time to progression was 30 days, 24 months, and 24 months, respectively.

The study was limited by the small sample size and retrospective design.

This study, although small, suggests that rituximab is a reasonable first-line treatment option for indolent CBCL with multiple lesions where local treatment is not effective or desirable.