SAN FRANCISCO Intralesional rituximab appears to be an effective and nontoxic therapeutic option for patients with multiple noncontiguous lesions of CD20-positive primary cutaneous B-cell lymphoma, according to Dr. Marco Ardigo.
Rituximab (Rituxanin North America and Japan; MabTheraelsewhere) is a chimeric monoclonal antibody directed against the CD20 antigen. It is often administered intravenously for the treatment of primary cutaneous B-cell lymphoma (CBCL). But the investigational use of intralesional rituximab has several compelling advantages: Notably, it does not produce systemic immunosuppression, and the cost is far lower because a much smaller amount of drug is used and prophylactic antibiotics are not required to prevent severe infections, Dr. Ardigo said at the annual meeting of the American Academy of Dermatology.
He reported on two patients with follicular CBCL and one with marginal zone CBCL whose multiple noncontiguous skin lesions made the prospect of local radiotherapy or surgical excision problematic. All three patients were free of systemic involvement. Their 15 nodular lesions up to 2.5 cm in diameter were treated with 20 mg of rituximab injected subcutaneously into each lesion three times per week, 1 week per month for 2 months. The maximum cumulative dose was 120 mg per lesion, in contrast to the usual intravenous regimen of 375 mg/m
Complete remission occurred by 2 months. The three patients have remained in remission through 10 months of ongoing follow-up.
No systemic side effects were noted, and no reduction in peripheral CD20-positive T cells occurred in the weeks following intralesional therapy. The only side effect reported was local pain during the injections, said Dr. Ardigo of the San Gallicano Dermatological Institute, Rome.
He noted that several other small case series have reported similarly favorable experiences with intralesional rituximab for primary CBCL, including one from the University of Zurich (Arch. Dermatol. 2000;136:374-8) and another from Geneva University (Br. J. Dermatol. 2006;155:1197-200).
Dr. Ardigo reported no financial conflicts of interest with commercial entities.