Long-term outcome of intravenous therapy with rituximab in patients with primary cutaneous B-cell lymphomas

The monoclonal antibody rituximab directed against the B-cell antigen CD20 was approved for the treatment of B-cell lymphomas and maintenance therapy in follicular lymphomas more than a decade ago. However, median follow-up in case series of intravenous rituximab therapy in primary cutaneous B-cell lymphomas (CBCL) lasts only up to 3 years. We retrospectively analysed a cohort of CBCL patients treated with rituximab to gain more long term information.

Eighteen patients, treated intravenously with rituximab for a primary cutaneous B-cell lymphoma [follicle centre lymphoma (PCFCL), n = 11; diffuse large B-cell lymphoma, leg type (PCLBCL, leg type), n = 5; marginal zone B-cell lymphoma (PCMZL), n = 2] were included. The response rate (RR), time to relapse (TTR), and course of the disease after treatment were analysed.

The overall RR was 89% (16 of 18 patients). Within the median follow-up time of 52 months, 81% (13 of 16) of patients experienced a relapse; the median TTR was 25 months. The duration of remission was significantly shorter in patients presenting with generalized skin lesions at start of therapy. Both nonresponding patients suffered from PCLBCL, leg type, with extracutaneous manifestations. In responders severe adverse events, the occurrence of extracutaneous dissemination or nodal lymphomas were not observed during follow-up.

Therapy with rituximab is effective and safe for the treatment of PCFCL, but relapses, in particular in patients with generalized skin involvement, are commonly observed. However, all patients with relapses responded well to treatment and therefore maintenance therapy does not seem to be indicated. Patients with PCLBCL, leg type, should receive chemotherapy in addition to rituximab.