Pathology of the Head and Neck

Oral Cavity Chapter 3 79Fig. 3.5. Median rhomboid glossitis showing extensive epithelialhyperplasia and fusing of rete processesFig. 3.6. Eosinophilic ulcers showing plump histiocytic nucleiand eosinophilscell carcinomas, with significantly adverse clinical consequences[129]. Below the epithelium there is often adense, band-like zone of hyalinisation that is sometimesmistaken for amyloidosis.The lesion often responds to antifungal treatment,but almost invariably recurs if the patient continues tosmoke. There does not appear to be any premalignantpotential and the dorsum of the tongue is a very uncommonsite for oral cancer.3.3.5 Eosinophilic Ulcer(Traumatic Ulcerative Granulomawith Stromal Eosinophilia)So-called eosinophilic ulcers are chronic but selflimitinglesions of a traumatic or reactive nature inwhich there is an intense inflammatory infiltrationwith a prominent eosinophilic component [45]. Despitetheir designation, about a third of these lesionsdo not undergo ulceration. Eosinophilic ulcers areseen most commonly in children and young adultsand are frequently painless. In infants, particularly,the condition has been called Riga-Fede disease[46]. Although these ulcers can be seen anywhere inthe oral mucosa, including the gingiva, they are mostcommon on the tongue and buccal mucosa. About athird of patients have a history of trauma, particularlya crush injury of the lingual muscle due to biting [43].The lesions are usually single and can be several centimetresin diameter. If left, most heal spontaneouslywithin 2 months, and this may be accelerated by incisionalbiopsy. Although recurrence tends to be uncommon,in one report 6 out of 15 cases were recurrentor multiple [43]. On the basis of the clinical andimmunocytochemical features it has been suggestedthat eosinophilic ulcers might be the oral equivalentof primary cutaneous CD30-positive lymphoproliferativedisorders [54].Microscopically, these lesions can be mistaken formalignancy. There is non-specific ulceration with underlyinginflamed granulation tissue (Fig. 3.6). Thereis an associated dense inflammatory infiltrate that extendsdeeply into the underlying muscle. The infiltrateconsists of lymphocytes and plasma cells, macrophages,polymorphonuclear leukocytes and mast cells. Eosinophilsare particularly numerous and they may form microabscesses.Macrophages are frequently conspicuousand can form sheets of cells with poorly demarcated cytoplasm,but large, vesicular nuclei with prominent nucleoliand a high mitotic frequency. These macrophages,together with damaged muscle cells showing sarcolemmalnuclear degeneration and regeneration, can give theerroneous impression of a lymphoma. In addition, theprominent eosinophilic component can lead to a mistakendiagnosis of Langerhans cell histiocytosis. Thiserroneous diagnosis is particularly likely in lesions involvingthe gingiva, where there may be associated resorptionof the underlying bone. Appropriate immunocytochemicalcharacterisation should avoid this confusion.3.3.6 Acute NecrotisingUlcerative GingivitisAcute necrotising ulcerative gingivitis (Vincent disease,trench mouth) is a relatively common oral disease. Althoughit is generally accepted that bacteria play a pivotalrole in the development of the disease, a specific causalagent has not been established. In the past the Gramnegativeanaerobes designated as Treponema vincentiiand Fusobacterium nucleatum were strongly implicatedand Treponema denticola [165] and Prevotella intermediaare some of the current candidate organisms.A wide variety of factors predispose to the developmentof the disease. The most important local factorsare cigarette smoking and poor oral hygiene. General