T:raumat ic eosinophili c granuloma(TEG) of the oral mucosa is considered to be a reactive benign lesion. which commonly manifests as an ulcer with elevated and indurated borders Clinically, this lesion simulates a malignant tumor. Histology shows a diffuse. dense, polyrnorphic, and eosinophil - rich cellular infiltra te. which extends deeply into the underlying soft t issues. A major constituent of infil trates is a population of mitotically active‘ la rge‘ atypi cal mononuclear cells. Immunohistologic evaluation of the large atypical cells has suggested a myofibroblastic 01' his tiocytic ol'igin. However, recent reports have shown that these cells are positive 1'01' CD30 antigen and it has been s llggested tha t a subset of TEG cOllld be included within the spectrum of CD30+ lymphoprolifer ative disorders. We have described 2 patients who had oral mllcosal lesions with features of TEG. ln patient 1. the lesiona l cells expressed CD3 .. CD43, LCA. Interestingly, the large cells were strongly CD30 positive. bl1t nega tive for CD68, CD45Ro‘ CD56, CD20. This case was interpreted as a CD30+ Iymphoproliferative disorder. In pa tient 2‘ t he la rge cell s showed strong posit ive for CD68, hut negative for CD30 The small lymphocytic cells ex prerssed CD3 This case was interpreted as an atypical histiocytic granuloma. Therefore, TEGs inclllde atypical histiocytic granllloma a long with the CD30+ lymphoid lesions. These findings suggested that TEG w0111d be a hete rogenous category of oral mucosal di sorders

• Jung Hoon Yoon(Department of Pathology, School of Dentistry, Chosun University)
• Sang Gun Ahn(Department of Pathology, School of Dentistry, Chosun University)