Odontogenic myxoma: a clinicopathologic study of 25 cases.

CONTEXT: Odontogenic myxoma is an uncommon tumor that has the potential for extensive destruction of the jaws.

OBJECTIVE

To document the clinical, pathologic, and behavioral features of odontogenic myxomas.

DESIGN

Histologic and immunocytochemical examinations were performed on odontogenic myxomas from 25 Chinese patients. Clinical and available follow-up data were analyzed.

RESULTS

In the present series, 13 were male and 12 female. The age at diagnosis ranged from 6 to 66 years, with a mean age of 28.8 years. Twelve tumors involved the mandible and 13 occurred in the maxilla, with a predilection for posterior areas. The posterior maxillary tumors frequently (9/10) involved the maxillary sinus. Of the 23 cases with radiographic records, 22 lesions presented with a multilocular appearance. Although 80% of the mandibular lesions showed a well-defined border, only 33.3% of the maxillary tumors were well-defined. Histologically, odontogenic myxomas were mainly composed of spindled or stellate-shaped cells in a mucoid-rich intercellular matrix. Tumors containing noticeable fibrous components were evident in 13 cases. Apart from 5 cases treated conservatively by enucleation, the remaining 20 cases were treated by relatively radical procedures, including block/segmental resection and partial or total maxillectomy or mandibulectomy. Follow-up data were available on 22 patients and only 1 patient initially treated by enucleation had a recurrence.

CONCLUSIONS

Odontogenic myxomas have a very bland histologic appearance that lacks atypia and may easily lead to misdiagnosis. The tumors are infiltrative with no capsulation and may recur after inadequate surgery.