[Odontogenic myxoma recurring after 11 years: case report and observations on this unusual neoplasm].

Odontogenic myxoma is usually a benign neoplasm, although it has the ability to infiltrate surrounding tissues thus becoming locally invasive. Furthermore, it has a moderately high recurrence rate and can sometimes display a really aggressive behaviour. An unusual case of a 48-y-old woman in whom odontogenic myxoma recurred 11 years after excision of the primitive lesion is reported. Although rare, the possibility of malignant evolution led us to consider which was the most appropriate management of both the neoplasm and the recurrence. A careful assessment of the clinical, radiographical, tomographical, histological and, if necessary, immunohistochemical features of the lesion allows a distinction to be made between lesions that are only locally invasive and the rarer, more dangerous aggressive lesions. In the first case we suggest that, where possible, a conservative treatment should be preferred, followed by close monitoring of the lesion over time. Since odontogenic myxoma is limited to the facial bones, excision may be uselessly disfiguring, above all in young patients. More aggressive surgical treatment should be reserved for lesions for which there is a strong suspicion of malignant transformation.