Systemic eight-cycle anti-CD20 monoclonal antibody (rituximab) therapy in primary cutaneous B-cell lymphomas--an applicational observation.

BACKGROUND: Primary cutaneous B-cell lymphomas (PCBCLs) are characterized by restriction to the skin and a variable but mostly favourable prognosis. Since 1997 the recombinant, chimeric anti-CD20 antibody rituximab has been used in patients suffering from non-Hodgkin's B-cell lymphomas. Different studies have shown that the effectiveness and safety in the treatment of patients with low-grade follicular lymphoma is comparable to or even higher than the standard CHOP chemotherapy. So far it has been unclear whether an extended duration of therapy leads to a benefit for the patients with PCBCL. OBJECTIVES: To evaluate the objective response rate, time to progression, remission quality and histological changes and to compare our data with the literature. PATIENTS/METHODS: Ten patients with PCBCL [eight with follicle centre cell lymphoma (FCCL), one with marginal zone lymphoma (MZL) and one with diffuse large B-cell lymphoma of the leg (DLBCL)] were treated by intravenous application of a chimeric antibody against the CD20 transmembrane antigen (rituximab) with a dosage of eight cycles, 375 mg m(-2) body surface, weekly. RESULTS: The treatment regimen resulted in clinical overall response in 9 of 10 patients, in particular there were seven complete responses (70%) plus two partial responses (20%). The median duration of remission (durable remission, DR) is 23 months (4-30 months) to date. Histological assessment of responses in four patients showed no tumour-specific infiltration. In two patients histology revealed a residual infiltration and in one patient an increasing infiltration. In two patients no histology was taken after treatment; one patient developed a new lesion. No severe side-effects occurred. Observed side-effects were two bacterial infections, two patients with shivering during infusion, one patient with sweating for months and one patient with persisting itching. As expected the B-cell count in peripheral blood was depressed in all patients after infusion. CONCLUSIONS: Intravenous therapy with eight cycles of the anti-CD20 antibody rituximab is a non-toxic and effective treatment for a subset of patients with PCBCL (relapsed, aggressive entity, old patients, multiple lesions) with a long DR.