下顎歯肉扁平上皮癌における骨吸収像

抄録

One hundred cases of materials for operation, diagnosed as Squamous cell carcinoma of the mandibular gingiva, were examined for bone invasion. According to the mode of the bone invasion, all of the cases were histologically classified into two groups : 1) invasive type (20%) and 2) expansive type (80%) . The invasive type of carcinomas were found to have a diffuse irregular margin, while the expansive type of carcinomas had a well-defined borderline.
The pathological changes during bone resorption were compared in both types of carcinomas. Histologically, in the invasive type of carcinomas, a large number of Howship's lacunae in the resorption phase were observed. In the expansive type of carcinomas, Howship's lacunae in the formation phase, with reversal lines, were relatively marked. Scanning electron microscopic observation of the invasive type of carcinomas revealed a marked destruction of the bone surface, with Howship's lacunae in the resorption phase and in the expansive type of carcinomas a smooth bone surface, with Howship's lacunae in the formation phase, was observed. Radiologically, the invasive type of carcinomas showed an irregular margin with a moth-eaten-like appearance, while the expansive type of carcinomas showed a smooth margin.
These results suggested that the invasive type of carcinomas had a higher tendency to grow rapidly and aggressively compared with the expansive type of carcinomas.