Contribution of immunologic technics to the characterization of lethal midline granuloma of unknown origin

: The lethal midline granuloma is a clinical entity characterized by a relentless ulceration of the upper airway involving the nose, the palate and the face, without any demonstrable etiology. We have applied the cell membrane immunostaining techniques to twelve cases. According to the results, it seems that most of the cases are in fact T-cell lymphomas with membrane staining consistent with either precursor or mature lymphoid T-cells. Some cases, however, exhibit an immunostaining pattern compatible with other origins, the proliferating cells belonging either to the B lymphoid or to the histio-monocytic lineages. We conclude that the lethal midline granuloma is an heterogeneous group of neoplastic diseases, in the most part close to a T cell lymphoma, but with a remarkable clinical unity.