平滑肌肉瘤是不常见的起源于平滑肌的恶性间叶性肿瘤,很少累及头颈部。作者报道1例着重分析平滑肌肉瘤的影像特征及其与手术和病理表现的联系。男性病人,69岁,右侧上颌及颊部肿物逐渐增大一个月,伴有右面部疼痛及鼻衄。于右上颌第二磨牙处取口腔粘膜活检,诊断为平滑肌肉瘤。患者有长期吸烟史,体检发现右上颌区的颊、腭侧均饱满,牙槽突的口腔粘膜有红斑,颅神经未受损。CT显示右侧上颌窦消失,其内充满软组织团 Leiomyosarcoma is an uncommon malignant mesenchymal tumor that originates in smooth muscle and rarely affects the head and neck. The authors report 1 case focuses on the analysis of the image features of leiomyosarcoma and its relationship with surgical and pathological findings. Male patient, 69 years old, right maxillary and buccal mass gradually increased for a month, accompanied by right facial pain and epistaxis. Oral mucosal biopsy was taken at the second maxillary second molar and the diagnosis was leiomyosarcoma. Patients with long-term smoking history, physical examination found the right maxillary cheek, palate side are full, alveolar process of oral mucosa erythema, cranial nerve is not damaged. CT showed disappearance of the right maxillary sinus, which filled with soft tissue mass