Eosinophilic ulcer of the oral mucosa: another histological simulator of CD30+ lymphoproliferative disorders.

Eosinophilic ulcer of the oral mucosa (EUOM), also known as traumatic ulcerative granuloma with stromal eosinophilia or Riga-Fede disease, is an uncommon benign self-limited lesion poorly described in the dermatological literature. It probably includes a spectrum of related disorders presenting as an ulcer with elevated indurated borders affecting the tongue, oral mucosa or lip. Histopathological findings are characteristic and consist of eosinophil-rich mixed infiltrates accompanied by a population of large mononuclear cells whose origins have been a matter of debate. Immunohistochemical studies of these cells have suggested a myofibroblastic or histiocytic origin. We present a 93-year-old woman with two episodes of self-healing ulcers on the upper lip and on the lingual mucosa, respectively. Histopathological findings on both biopsies were consistent with EUOM and showed the presence of large atypical CD30+ lymphocytes. Some recent reports have also shown positivity for the CD30 antigen, raising the possibility that a subset of EUOM could be included within the spectrum of CD30+ lymphoproliferative disorders. This finding most likely suggests that EUOM can represent another histological simulator of CD30+ lymphoproliferative disorders.