LAUSR

Rationale: Mucoepidermoid carcinoma (MEC) is the most common primary salivary gland malignancy. Ectopic MEC can occur in any part of the body, however, only 2% to 4% of MEC could be detected in the jaw, which is named intraosseous mucoepidermoid carcinoma (IMC). IMC is usually a low-grade carcinoma. Uni- or multilocular radiographic lesions should be differential diagnosed with ameloblastoma, odontogenic cysts, and glandular odontogenic cyst (GOC). Radical surgery may prefer for a favorable prognosis. Whereas IMC can recur long after the operation, a long-term follow-up system should be implemented. Owing to its rarity and controversial issues, we report a case report and review the literature to discuss its clinical features, treatments, radiological, and histological characteristics. Patient concerns: The patient presented with a 2-month history of mild pain in the lower left posterior jaw without history of surgery or trauma to the mandible. Diagnoses: Routine postoperative pathology showed that the mass was consistent with a mandibular mucoepidermoid carcinoma. Intervention: Radical surgery and digital mandibular reconstruction were performed. Outcome: Postoperative imaging showed that the height of the mandible and the symmetry of the mandible were satisfactory. The patient was also satisfied with her appearance. Follow-up has been established. Lessons: Effective surgical treatment allows patients to have a favorable prognosis. A long-term follow-up system should be practiced, because local recurrences and regional metastasis could happen even after decades.