Mandible & maxilla
Malignant odontogenic tumors
Ameloblastic carcinoma
Last author update: 1 December 2015
Last staff update: 17 April 2023
Copyright: 2004-2019, PathologyOutlines.com, Inc.
PubMed Search: Ameloblastic carcinoma [title] mandible maxilla
Table of Contents
Definition / general | Epidemiology | Sites | Etiology | Clinical features | Diagnosis | Prognostic factors | Radiology description | Radiology images | Case reports | Treatment | Clinical images | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Differential diagnosis | Additional referencesCite this page: Magliocca K, Martinez A. Ameloblastic carcinoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/mandiblemaxillaameloblasticcarcinoma.html. Accessed October 2nd, 2023.
Definition / general
- Rare epithelial odontogenic tumor with histologic features of an ameloblastoma with marked cytologic atypia
Epidemiology
- Rare, < 100 case reports in English literature
- Represent < 1% of all odontogenic tumors
Sites
- More common in mandible (~80%), particularly posterior mandible
- Rare reports of maxillary involvement
Etiology
- Majority arise de novo
- Less commonly arise from pre-existing ameloblastoma, and are considered secondary or dedifferentiated lesions
Clinical features
- May be painful as they cause expansion of the jaw, grow rapidly and perforate the cortex
- "Expansion" or "hard mass" is the most common chief complaint
- Other complaints include toothache, ulceration, trismus and facial asymmetry
Diagnosis
- Requires clinical, radiologic and pathologic correlation
Prognostic factors
- Malignant lesions have 30% recurrence rate, 22% metastasis rate
- 5 year survival is 70% without metastases, 20% with metastases
Radiology description
- On radiograph, well-defined unilocular or multilocular radiolucent lesion
- Often shows cortical expansion with perforation
Radiology images
Images hosted on other servers:
Orthopantomogram
Lucent lesion
Axial non-contrast CT
Axial MRI
Case reports
- 16 year old boy with metastasis to skull and lung (Dentomaxillofac Radiol 2010;39:449)
- 24 and 30 year old men (J Oral Maxillofac Pathol 2014;18:S96, J Clin Diagn Res 2015;9:ZD27)
- 66 year old man and 67 year old woman (Am J Case Rep 2015;16:415, J Maxillofac Oral Surg 2010;9:198)
Treatment
- Composite surgical resection, with adjuvant radiation and chemotherapy as appropriate
Clinical images
Images hosted on other servers:
Extraoral swelling
Pus discharge
Intra-oral swelling
Gross images
Images hosted on other servers:
Resected specimen
Microscopic (histologic) description
- Variable features of amelobastoma: peripheral palisading, reverse polarization, stellate reticulum
- Features of malignancy include cytological atypia, high N:C ratio, increased mitoses with atypical forms, necrosis
Microscopic (histologic) images
Contributed by Kelly Magliocca, D.D.S., M.P.H.
Ameloblastic carcinoma
Images hosted on other servers:
Low power
Higher power
Cytological atypia
Necrosis
Differential diagnosis
- Ameloblastoma
- Histologically, may share some of same features such as peripheral palisading, reverse polarization and stellate reticulum, but should not show features of malignancy (pleomorphism with hyperchromasia, atypical mitoses)
- Clear cell odontogenic carcinoma
- Malignant epithelial odontogenic tumor composed primarily of nests and islands of clear cells
- May have focal peripheral palisading similar to ameloblastoma, but not as much cytologic atypia as ameloblastic carcinoma
- More common in anterior mandible
- EWSR mutation
- Malignant ameloblastoma
- Like amelobastoma histologically but termed "malignant" after discovery of metastases
- Should not show any cytologic features of malignancy
- Metastatic disease
- Primary intraosseous squamous cell carcinoma
- Carcinoma composed of moderately to poorly differentiated squamous epithelial cells with variable keratinization
- Also derived from odontogenic epithelium
