Mandible & maxilla
Malignant odontogenic tumors
Odontogenic sarcoma / ameloblastic fibrosarcoma
Last author update: 1 January 2016
Last staff update: 13 October 2022
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PubMed Search: Ameloblastic fibrosarcoma [title] mandible
Table of Contents
Definition / general | Terminology | Epidemiology | Sites | Etiology | Clinical features | Diagnosis | Radiology description | Radiology images | Prognostic factors | Case reports | Treatment | Clinical images | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Differential diagnosis | Additional referencesCite this page: Martinez A. Odontogenic sarcoma / ameloblastic fibrosarcoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/mandiblemaxillaameloblasticfibrosarcoma.html. Accessed January 18th, 2025.
Definition / general
- Rare mixed odontogenic tumor that consists of a benign ameloblastic epithelium and a malignant mesenchymal stroma
- Thought to be malignant counterpart to ameloblastic fibroma
Terminology
- Ameloblastic fibrosarcoma
- Ameloblastic fibrodentinosarcoma: used when dentin is present within the malignant stroma
- Ameloblastic fibroodontosarcoma: used when enamel is present within the malignant stroma
Epidemiology
- Rare, < 100 case reports in English literature
- More common in males (1.5 - 1.6:1)
- Mean age: 3rd decade
Sites
- More common in mandible (80%); favors posterior mandible
- Can have maxillary involvement; may extend into sinus
Etiology
- Close to half (45%) arise from ameloblastic fibroma
- De novo tumors tend to occur in younger patients
Clinical features
- Patients often present with swelling and pain
- Occasionally painless facial mass with accompanying paresthesia
Diagnosis
- Diagnosis dependent on clinical, radiologic and pathologic correlation
Radiology description
- Appears as an expansive, multilocular radiolucent lesion
- Often shows cortical perforation
Radiology images
Images hosted on other servers:
Ill-defined radiolucent lesion
Panoramic radiographs
Multilocular radiolucent lesion
CT
Isodense area
Prognostic factors
- Locally aggressive with high (~45%) recurrence
- Multiple recurrences are not uncommon
- Distant metastases are not as common
Case reports
- 22 year old woman and man (Case Rep Pathol 2015;2015:245026, Exp Ther Med 2014;8:1463)
- 26 year old man with ameloblastic fibrosarcoma arising from recurrent ameloblastic fibroma (Am J Case Rep 2015;16:548)
- 28 year old woman (J Oral Maxillofac Pathol 2013;17:424)
Treatment
- Surgical resection with a wide margin is the optimal treatment strategy
- Adjuvant chemotherapy and radiotherapy as needed; may reduce the recurrence rate and enhance the quality of life
Clinical images
Images hosted on other servers:
Gross swelling
Swelling, lower left mandible
Swelling without ulceration
Massive intraoral extension
Gross images
Images hosted on other servers:
Left half of mandible
Cross-section
Microscopic (histologic) description
- Biphasic with benign epithelium and malignant stroma:
- Benign odontogenic epithelium with “ameloblastic” appearance of basaloid odontogenic epithelium
- Strands, cords and nests of odontogenic epithelium
- Focally, larger tumor islands may show peripheral palisading, reverse polarization, stellate reticulum-like material
- Malignant stroma consisting of variably spindled cells with pleomorphism, hyperchromasia, increased mitoses
- Stromal cells can be arranged in a herringbone or storiform pattern
- Benign odontogenic epithelium with “ameloblastic” appearance of basaloid odontogenic epithelium
Microscopic (histologic) images
Images hosted on other servers:
Benign odontogenic epithelium
Odontogenic epithelium
Low grade malignant neoplasm
Small nests, islands
Epithelial dysplasia
AE1/AE3, vimentin, Ki67
PCNA, p53
Ki67, p53
Pan-cytokeratin, vimentin, Ki67
Differential diagnosis
- Ameloblastic fibroma
- Tends to occur at younger age (first two decades of life)
- Histologically, may share same features within the odontogenic epithelial component strands, cords and islands that may exhibit peripheral palisading, reverse polarization and stellate reticulum
- However, stroma is less cellular and more primitive, delicate and lobular in appearance
- Lacks sarcomatous features (pleomorphism, hyperchromasia, atypical mitoses)
- Some case reports indicate Ki-67 in the stroma is higher in ameloblastic fibrosarcoma when compared to ameloblastic fibroma (10x increase)
- Ameloblastoma
- Similar to ameloblastic fibrosarcoma and ameloblastic fibroma, may show some histological overlap of the basaloid odontogenic epithelial islands (peripheral palisading, reverse polarization, stellate reticulum)
- Does not have malignant stroma (spindle cells with pleomorphism, hyperchromasia, atypical mitoses)
- Fibrosarcoma
- Rare, malignant tumor of fibroblasts with herringbone architecture and variable collagen
- Usually deep soft tissue of lower extremities or trunk, only rarely in retroperitoneum or mediastinum
- Tends to occur in slightly older population (ages 40 - 55)
- Should have no odontogenic or ameloblastic epithelial component
Additional references
