Yamamoto Kazuhiko, Matsusue Yumiko, Kurihara Miyako, Takahashi Yuka, Kirita Tadaaki
Department of Oral and Maxillofacial Surgery, Nara Medical University.
Open Dent J. 2013 Nov 13;7:152-6. doi: 10.2174/1874210601307010152. eCollection 2013.
A 74-year-old male patient consulted us for an elastic firm mass in the right buccal mucosa. CT examination revealed a well-circumscribed oval cystic lesion in the anterior region of the masseter muscle. On MRI, the lesion showed a low signal on T1-weighted image and a high signal on T2-weighted image. Aspiration biopsy demonstrated the presence of squamous cells in whitish liquid. Under the diagnosis of epidermoid cyst, the lesion was intraorally extirpated under general anesthesia. The lesion was cystic at the size of 30 × 25mm. Histologically, the cyst wall was lined with parakeratinized squamous epithelium corrugated on its surface, the basal layer of which consisted of cuboidal cells showing palisading of the nuclei. Immunohistochemically, the lining epithelium was positive for CK17 and negative for CK10. The basal and suprabasal cells were labeled for Ki-67 at a relatively high rate. These features are compatible with those of keratocystic odontogenic tumor.
一名74岁男性患者因右侧颊黏膜出现一个质地坚韧的弹性肿物前来就诊。CT检查显示在咬肌前部区域有一个边界清晰的椭圆形囊性病变。在MRI上，该病变在T1加权图像上呈低信号，在T2加权图像上呈高信号。穿刺活检显示白色液体中存在鳞状细胞。在诊断为表皮样囊肿后，在全身麻醉下经口腔将病变切除。病变为囊性，大小为30×25mm。组织学上，囊肿壁内衬表面呈波纹状的不全角化鳞状上皮，其基底层由细胞核呈栅栏状排列的立方细胞组成。免疫组织化学检查显示，内衬上皮CK17阳性，CK10阴性。基底层和基底上层细胞Ki-67标记率相对较高。这些特征与角化囊性牙源性肿瘤相符。
