Pemphigus paranéoplasique révélateur du développement d'un sarcome à cellules dendritiques à partir d'une tumeur de Castleman pulmonaire

This is a case of paraneoplastic pemphigus of unusual clinical and biological expression: exclusively mucosal involvement with obliterating bronchiolitis, explained by the isolated presence of antibodies recognizing envoplakin, without anti-desmoglein. The transformation of the Castleman tumor into a sarcoma may have unmasked intra-cellular antigens (plakins), initiating the specific immune reaction.