Our intention in describing this case was to demonstrate our singular experience in the management of a patient with a unicameral cystic lesion diagnosed as unicystic ameloblastoma (UA) after clinical, radiographic, and histopathologic correlation. One main question of Dr Ide concerned the pathologic diagnosis of UA in this patient. Based on Figure 2, C and D , the radiographic picture, and the operative findings, he claimed that a better diagnosis was adenomatoid odontogenic tumor rather than UA. The pathologic diagnosis suggesting ameloblastoma was based on the finding of squamous epithelium lining, with basal cell palisading and vacuolization of cytoplasm of the cells in the center of proliferation showing a plexiform and organoid pattern. The histopathologic findings suggested (but were not conclusive for) ameloblastoma. For the conclusive diagnosis of UA, it was necessary to correlate the clinical and radiographic findings, including the location of the lesion. The histologic patterns shown in Figure 2 were interpretated as a morphologic variation of ameloblastoma as described by de Andrade Sobrinho et al ; however, as justified by Ide et al, the differential diagnosis of adenomatoid adontogenic tumor must be considered, including its rare location in the posterior mandible.
It was not possible to perform calretinin immunohistochemical staining to corroborate the diagnosis of ameloblastoma because of the small amount of residual tissue in the paraffin block. The initial diagnosis of ameloblastoma was based on clinical and radiographic findings, but such diagnoses are not always correct. Only histopathologic examination can provide a definitive diagnosis when clinical and radiographic findings are inconclusive.
The treatment plan proposed in this clinical case was based on a histopathologic diagnosis, considering the age of the patient, emotional factors affecting the patient and his parents, the location of the disease, the total surgical enucleation, and, in particular, the possibility of clinical and radiographic follow-up. The choice of treatment and the factors that must be considered when planning surgery are controversial. When UA is treated conservatively, there is a significant success rate, although the possibility of recurrence remains. Many theories have been presented regarding the best treatment for ameloblastomas, primarily based on their clinical characteristics and biologic behaviors. Surgical approaches can be classified as radical or conservative. Classically, solid ameloblastomas have been treated by radical surgical excision with a safety margin of 1 to 2 cm from the normal bone. On the other hand, UAs have typically been removed by enucleation, as though they were cysts.
For Nakamura et al, a conservative treatment involving marsupialization and enucleation followed by bone curettage was effective, reducing the need for surgical resection. Each ameloblastoma case must be analyzed individually and carefully, but conservative treatment should be strongly considered when the tumor is in its initial stages, even if there is a greater risk of recurrence. Regardless of the technique used, it is essential to maintain clinical and radiographic follow-up for these lesions, because more than 50% recur within 5 years after surgery. However, some can recur 10 to 15 years later.
The course of treatment we proposed was based on the results of anatomic and pathologic examinations, considering the location, form, and total enucleation of the lesion and the patient’s age. Under no circumstances can this course be considered inadequate, and the need for radical treatment would have been reconsidered in case of recurrence, as determined by clinical and radiographic follow-up. The choice not to use cryotherapy after alveolar curettage was made because the initial radiographic and clinical impressions after enucleation suggested a dentigerous cyst, confirming the initial diagnosis with histologic results. Thus, based on the available evidence, we proceeded with a nonradical approach.
Our goal was not to propose a new therapeutic treatment or to encourage maxillofacial surgeons to adopt this treatment. However, there is a need to emphasize the discussion of treatment plans that offer a controlled cure in consideration of not only the histologic diagnosis but also the lesion type, the patient’s age, the radiologic results, and the possibility of follow-up.