Oral keratoses : a clinical, pathological and immunological study

• Main Author: Robertson, William Duncan
• Published: University of Edinburgh 1991
• Subjects: 616.5
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.661261

The diagnosis of a patient presenting with an oral keratosis is the first stage in the management of the patient. Diagnosis is based on a combination of patient history, clinical examination and laboratory investigations. The aim of this thesis was to identify factors which may be helpful in the diagnosis of oral keratoses. It is based on a prospective study of 159 patients being examined haematologially, immunologically and histopathologically. Two main groups of keratoses were identified by the presence or absence of an associated inflammatory cell infiltrate. Infiltrated keratoses comprised patients diagnosed as lichen planus, leukoplakia, discoid lupus erythematosus, candidal leukoplakia and squamous cell carcinoma. Non infiltrated keratoses also comrpised patients diagnosed as leukoplakia but also comprised frictional and smoking keratoses and hereditary keratoses. A third category, intermediate infiltrated leukoplakia was distinguished by changeable clinical and histopathological appearances during the study period. Individual patient diagnosis followed clinical examination and immunological and histopathological investigations. Cross-tabulation of the diagnostic categories with the clinical presentations of the keratoses showed that the clinical appearances may be common to different diagnostic categories. Non infiltrated leukoplakia was seen frequently to involve the floor of mouth. All categories of keratoses had a high proportion of patients currently taking medication: non steroid anti-inflammatory drugs were more frequently taken by patients with erosive lichen planus (29%) than those with non erosive lichen planus (3%). Abnormal intestinal sugar permeability was detected in 65% and 60% of lichen planus and infiltrated leukoplakia patients respectively but not in any patients with non infiltrated keratoses. Haematological deficiencies were detected in 23 patients (14.4%) of the whole study group and were related particularly to lichen planus and non infiltrated leukoplania, 22.5% and 19.2% respectively. Tobacco habits were positively associated with categories of leukoplakia and squamous cell carcinoma. Patients with lichen planus had significantly lower tobacco and alcohol use than infiltrated, non infiltrated leukoplakia and the squamous cell carcinoma categories. Histopathological assessment of the oral keratoses did not identify any singular diagnostic characteristic. Epithelial dysplasia was seen in lichen planus, leukoplania and squamous cell carcinoma. Inflammatory infiltrate phenotypes were identified using the immunoperoxidase system and quantitative differences existed between the diagnostic categories. The T4/T8 ratio was highest for the frictional and smoking keratoses and lowest for intermediate infiltrated leukoplakia. The intermediate infiltrated leukoplakia category also showed significantly lower serum immunoglobulins (IgG, IgA and IgM) than other diagnostic categories. No evidence of blood or lesional lymphocytes was found. Co-culture experiments suggest lesional cells exert suppressor effects for squamous cell carcinoma and not for the categories of leukoplakia.