Abstract:

Objective To investigate the clinicopathological features of odontogenic myxoma (OM). Methods The clinicopath-ologic data of 15 patients with odontogenic myxoma(OM) diagnosed by routine pathology in Stomatological Hospital Affiliated to Nanjing Medical University from January 2013 to June 2023 were retrospectively analyzed. Results (1)The most common cases were female(66.7%), 20-40 years old(73.3%), mandible(60.0%)and posterior dental area(93.3%). (2)The characteristic imaging findings were multilocular cystic low-density radiography, resembling honeycomb/tennis racket/soap bubble structures. (3)Microscopically, star or spindle tumor cells can be seen scattered in the background of light blue mucoid matrix, and occasionally a few odontogenic epithelial clusters. (4)In 15 odontogenic myxoma(OM) samples, ①β-catenin was not expressed in 1 case of mucous type, partially or diffusely expressed in 6 cases, not expressed in 2 cases of fibrous type, partially or diffusely expressed in 6 cases; ②CD34 and S100 were negative; ③Ki-67 index was lower than 1%. (5)Of the 15 patients, only one relapsed, and the rest had a good prognosis. (6)Surgical treatment is the main treatment plan at present, and the appropriate surgical plan should be selected according to the size of the tumor, the scope of the lesion and the situation of the patient. Conclusion Although odontogenic myxoma is a benign tumor, it is locally invasive and recurrent. It is necessary to distinguish it from low-grade malignant myxosarcoma, chondromyxoid fibroma and odontogenic fibroma. Understanding of and familiarity with its clinicopathological features is helpful to its diagnosis and improving the prognosis of patients.

Key words: odontogenic myxoma, clinicopathological features, differential diagnosis