Abstract
A case of pilomatorixoma in the right preauricular region in a 6-year-old man is reported. A solitary bone-hard subcutaneous nodule (1cm×2cm) was in the buccal fat, which had no relationship to a parotid gland. Above observations were possible by radiography, CT-scan and ultrasonography before the operation. The nodule was surgically removed easily. Histopathological examination showed basophilic cells and shadow cells in the tissue. It is a typical appearance of pilomatorixoma.
Previous reports of pilomatorixoma are also reviewed. Many cases have been reported by dermatologists, but only 18 cases have been reported by otorhinolaryngologists in Japan before our report: the first report by an otorhinolaryngologist was by Masayuki Nagakura in 1968. Pilomatorixoma is often observed in the head and neck region, therefore, otorhinolaryngologists should be aware of the lesion.
Pilomatorixomas often show non-typical clinical appearances: perforating type, cystic type, bullous appearance type, eruptive type and etc. Pilomatorixomas usually occurs solitary and rarely occurs multiple. Some of multiple pilomatorixomas are thought of one of the symptoms of myotonic dystrophy.
In conclusion, preoperative diagnosis is very important, therefore, radiography, CT-scan and ultrasonography are significant for differential diagnosis of pilomatorixoma.
