Rapid onset of cutaneous squamous cell carcinoma in patients with rheumatoid arthritis after starting tumor necrosis factor alpha receptor IgG1-Fc fusion complex therapy

Tumor necrosis factor a (TNF-alpha) is now believed to be a major contribut or to the pathogenesis of the synovitis and joint destruction in rheumatoid arthritis. Etanercept is a recombinant human TNF-alpha receptor Fc fusion protein consisting of a dimer of the extracellular portion of two p75 TNF-a lpha receptors fused to the Fc portion of human IgG1. Etanercept produces s ignificant dose-dependent improvements in disease activity. We describe 7 p atients who experienced 1 or move squamous cell carcinomas that showed rapi d growth and arose over a 2- to 4-month period of etanercept therapy Solubl e TNF-alpha receptor therapy through inhibition of a T(H)1 cytokine pattern and inhibition of the direct and indirect cytotoxic effects of TNF-alpha m ay initially decrease mechanisms for controlling subclinical tumors and may contribute to the histologic features seen within these tumors. However, p rolonged TNF-alpha inhibition may have some antitumor effects.