Favorable outcome of primary cutaneous marginal zone lymphoma treated with intralesional rituximab.

Primary cutaneous marginal zone lymphoma (PCMZL) is an indolent disease. Treatment options include excision, local irradiation, interferon-alpha or chemotherapy. We present two patients with PCMZL and multiple skin lesions successfully treated with intralesional administration of the anti-CD20 monoclonal antibody rituximab. The first presented with four red skin lesions and the second with two. Biopsy of the largest lesion revealed marginal zone B-cell lymphoma in both patients. There was no evidence of systemic involvement in either patient. Both patients were treated with intralesional rituximab for 18 consecutive weeks. Skin lesions gradually regressed. Apart from mild local pain during the injection, no other adverse effects were observed. In conclusion, rituximab can be safely administered intralesionally in patients with PCMZL and can produce disease remission.