2005 年 3 巻 3 号 p. 163-166
The rare case of a mucous retention cyst in the upper lip, possibly caused by a cavernous hemangioma with thrombi, of a 74-year-old man is reported. Three mucous retention cysts were located under the suspected cavernous hemangioma with thrombi. The lumen of the largest cyst was lined with double-layered flattened epithelium and a few goblet-like cells ; the lumen of the other smaller cysts was lined with short columnar or cuboidal epithelium and no goblet-like cells. No other cause of duct obstruction was observed in the labial gland. In the present case, duct obstruction caused by a long-standing hemangioma apparently led to the formation of mucous retention cysts and the considerable retention of a mucous substance made the cyst larger, resulting in flattened epithelium.
