Midfacial necrotizing lesions.

Because of obvious therapeutic and prognostic implications, as definitive a pathologic diagnosis as possible is necessary for necrotizing lesions of the midfacial mucous membranes. In the beginning of the diagnostic process, the lesions are placed under the noncommittal rubric of midfacial necrotizing lesions, thus forever avoiding confusing nomenclature such as lethal midline granuloma. Following this, the lesions are approached with the full appreciation they may be (1) localized or part of a systemic illness; (2) neoplastic or non-neoplastic; (3) caused by a specific agent or organism or be seemingly idiopathic; (4) self-limited or progressively destructive in varying degrees of severity; (5) characterized by a granulomatous or nonspecific tissue reaction with or without vasculitis; and (6) impossible to classify without clinicopathologic correlation. To illustrate these points, a number of necrotizing lesions, including sarcoidosis, Wegener's granulomatosis, and the lymphomatoid granulomatosis-polymorphic reticulosis group are presented.