Ameloblastic carcinoma is a rare, malignant, odontogenic epithelial tumour with significant metastatic potential, requiring radical surgical intervention and strict post-operative surveillance. Diagnosis requires histological evidence of an ameloblastoma with cytological atypical regardless of the presence or absence of metastases.(1)
Epidemiology:
There was only 104 reported cases of ameloblastic carcinoma (all types) between 1984 and 2009.(1) A number of authors have performed literature reviews pertaining the secondary type, yielding significantly varying aggregates, reflecting the inconsistency and paucity in classification. Compared to the primary ameloblastic carcinoma which arises de novo,…show more content… Approximately two-thirds of cases develop in the mandible (mainly posterior segment) and one-third in the maxilla.(6) The most common presenting feature of ameloblastic carcinoma is swelling, although associated pain, trismus, dysphonia, paraesthesia, gingival bleeding, oroantral fistulae and epistaxis commonly occurs.(4) Imaging such as orthopantomograph and computed tomography are important aspects of tumour assessment. Orthopantomograph is useful in showing a poorly defined radiolucency (unilocular or multilocular), which also may have a honeycomb appearance with tooth root resorption. Computed tomography (CT) and Magnetic resonance imaging (MRI) are useful in obtaining more detail of the disease process and affected anatomy. The course of the disease may vary with perforation of the cortical plate, extension into regional soft tissues and multiple recurrent and metastatic lesions all being…show more content… Ameloblastic carcinomas (all types) progress rapidly with extensive local destruction and metastatic spread if intervention is delayed. A recurrence rate of 15-25% following wide surgical resection and 90% following local curettage alone has been demonstrated in the literature.(8)
The most common site of metastasis is the lung, however other sites have been described such as brain, bone, liver, and regional lymph nodes.(1, 6, 13) A contiguous neck dissection should be performed for both diagnostic staging and therapeutic purpose. Pre-operative testing such as MRI and 18F-α-methyl tyro¬sine positron emission tomography may assist in differentiating benign from malignant regions and thus avoid excess resection, functional loss and poor facial cosmetic outcome. Non-operative treatment such as radiotherapy or chemotherapy need to be considered in cases of locally advanced or metastatic disease deemed not suitable for surgical resection. There may be a particular role for pre-operative radiotherapy in decreasing the tumour size and possibly treating some rapidly growing tumours before a radical resection. There is a potential benefit for adjuvant radiotherapy for close/positive margins or in tumours with nodal metastases; however, there is limited evidence to support radio sensitivity. Radiotherapy
