Reduction of tumor burden and stabilization of disease by systemic therapywith anti-CD20 antibody (rituximab) in patients with primary cutaneous B-cell lymphoma

BACKGROUND, Primary cutaneous B-cell lymphoma (CBCL) is characterized by re striction to the skin, a high incidence of recurrence after various treatme nt modalities, and a variable but mostly favorable prognosis. METHODS. Ten patients with long standing primary CBCL (3 with follicular CB CL, 5 with cutaneous, large B-cell lymphoma, 1 with diffuse large cell lymp homa, and 1 with extranodal large cell lymphoma) were treated by intravenou s application of a chimeric antibody against the CD20 transmembrane antigen that is present on malignant and normal B-cells. In 6 of 10 patients, seve ral treatment attempts either had failed or could not be used due to severe side effects or underlying disease. RESULTS. The treatment regimen resulted in two complete regressions, five p artial responses, and one mixed response, and two patients did not respond to the treatment. No severe side effects occurred, except for slight pain i n the nodules after infusion and an urticarial reaction at the tumor sites. A prolonged, complete disappearance of B-cells from the peripheral blood w as observed. The immunoglobulin serum levels and inflammatory markers were unchanged. Histologic examination of biopsies from two regressing tumor nod es showed necrotic tumor cells and infiltration with CD8 positive cells. CONCLUSIONS, Intravenous therapy with the anti-CD20 antibody rituximab is a nontoxic and effective treatment for patients with primary cutaneous B-cel l lymphoma. Cancer 2000;89:1835-44. (C) 2000 American Cancer Society.