Lichenoid paraneoplastic pemphigus in the absence of detectable antibodies.

Paraneoplastic pemphigus (PNP) has been described as an antibody-mediated mucocutaneous disease occurring almost exclusively in patients with lymphocytic neoplasms. We describe 4 patients with the clinical features of the lichenoid variant of PNP in the absence of detectable autoantibodies. On the basis of these findings, we conclude that the spectrum of PNP likely includes patients with disease predominantly or exclusively mediated by cytotoxic T cells rather than autoantibodies. The pathophysiology and range of PNP disease are likely more complex than was initially believed.