Hemimaxillectomy for Desmoplastic Ameloblastoma with Immediate Temporalis Flap Reconstruction
Ameloblastoma is one of the most common benign odontogenic tumors encountered by oral & maxillofacial surgeons. Its aggressive behavior can lead to debilitating consequences, including significant facial deformity and high potential for pathologic fracture. While the anatomical distribution and progression of this pathology remains fairly consistent, alternative manifestations follow an atypical clinical course. We present a case involving one of these variants, the desmoplastic variant.
The desmoplastic variant exhibits key features not seen in the more traditional ameloblastoma: more common in the maxilla, which could lead to more devastating outcomes if not treated promptly; and a mixed radiopaque/radiolucent lesion, differing from the purely radiolucent lesion of the traditional type. Much like the unicystic and multilocular entities, this particular variant is treated with aggressive resection of the bony segment involved. In most instances, hard tissue grafting is used to reconstruct the resected segment. In our case, we elected for an alternative method in hopes of reducing post-operative morbidity, while also increasing the rate at which the patient recovered. We chose to use a temporalis flap to reconstruct the area.
Patient and Method:
A 54 year-old female patient presented complaining of mobility of her upper left maxillary teeth. Upon clinical and radiographic examination, a mixed radiopaque/radiolucent lesion was discovered and subsequently biopsied. Diagnosis by the hospital pathologist was that of an ameloblastoma; however a second consultation was obtained from an oral pathologist, who then changed the diagnosis to the desmoplastic variant. The severity of the diagnosis was compounded by the close proximity of the tumor to the orbit. The patient then underwent a hemimaxillectomy using a Webber Ferguson approach to remove the tumor. The resected site was then immediately reconstructed with the ipsilateral temporalis muscle, obtaining primary closure and preventing damage to adjacent vital structures.
Patient was then discharged in stable condition, but re-admitted the following week due to increased swelling. A second surgery was performed to drain a large hematoma of the newly reconstructed palate. Her recovery was uneventfully, and she was followed for several months without significant changes. The patient continues to progress without any complications as her palate remains closed.
Conclusion:
Treatment of the desmoplastic variant of the ameloblastoma can vary, depending on the location and severity of the tumor. The standard method of care is usually resection, followed by hard tissue grafting to achieve functional and esthetic satisfaction. We, however, chose the temporalis flap without concurrent hard tissue grafting because of its close proximity to the area of resection.
The temporalis flap is an axial pattern flap, which enabled us to achieve soft tissue closure at the time of surgery, preventing potential post-operative complications, such as difficulty in speech and oral nasal fistula formation. By achieving proper soft closure, we have allowed for the possibility of future hard tissue grafting for oral rehabilitation. Options such as a vascularized free fibula flap were not used because of the post-operative patient discomfort and higher chance for complications. By using an axial pattern temporalis flap in the reconstruction of a hemimaxillectomy, the surgical time and expense was greatly reduced, as well as decreased morbidity to the donor site.
References:
Kato, H et al. A case of desmoplastic ameloblastoma occupying maxillary sinus. Contemp Clin Dent. 2011 Jul;2(3):234-6. doi: 10.4103/0976-237X.86474
Pia, F et al. Intraoral transposition of pedicled temporalis muscle flap followed by zygomatic implant placement. J Craniofac Surg. 2012 Sep;23(5):e463-5. doi: 10.1097/SCS.0b013e31825b34f6.