Ameloblastic fibrosarcoma of the mandible: a case report and brief review of the literature

Abstract

Ameloblastic fibrosarcoma is an uncommon odontogenic tumor composed of a benign epithelial component and a malignant ectomesenchymal component most frequently seen in the third and fourth decades of life. It mainly presents as a painful maxillary or mandibular swelling. Radiographs show a radiolucent mass with ill-defined borders. Radical surgical excision and long-term follow-up are the suggested treatment. We report the case of a 22-year-old female with a 2-month history of an asymptomatic swelling in her left mandible. Examination revealed an exophytic growth measuring 3 × 3 cm extending from the mandibular left first premolar to the second molar. The patient underwent a left hemimandibular resection. Histopathological examination revealed a biphasic tumor composed of inconspicuous islands of benign odontogenic epithelium and an abundant malignant mesenchymal component with marked cellularity, nuclear pleomorphism, hyperchromatism, and moderate mitotic figures with clear margins; one year after the surgical procedure, the patient is clinically and radiologically disease-free.

Figure 1

((a) and (b)) Extraoral evaluation revealed a gross swelling over the left mandible.

Figure 2

(a) Biphasic tumor composed of islands of benign odontogenic epithelium and an abundant malignant mesenchymal component. H&E stain, ×50. (b) The malignant mesenchymal component consists of plump and spindle stromal cells which show mild to moderate cytologic atypia and numerous mitotic figures arranged in storiform and herringbone fashion. H&E stain, ×100.

Figure 3

(a) Reactivity to Cytokeratin AE1/AE3 in the epithelial component, lack of reactivity in the mesenchymal component. Immunohistochemical stain with anti-Cytokeratin AE1/AE3 antibody, ×50. (b) Reactivity to Vimentin in the mesenchymal component. Immunohistochemical stain with anti-Vimentin antibody, ×400. (c) Reactivity to Ki67 in the mesenchymal component with a labeling index of 30%. Immunohistochemical stain with anti-Ki67 antibody, ×50.

Figure 4

Panoramic radiograph (a) and axial CT scan (b) revealing an ill-defined radiolucent lesion around an impacted mandibular left first molar.

Figure 5

Gross photograph of the cut surface of the left half of the mandible showing a solid gray tumor mass.

Figure 6

(a) Reactivity to PCNA in both components. Immunohistochemical stain with anti-PCNA antibody, ×50. (b) Reactivity to p53 only in the mesenchymal component. Immunohistochemical stain with anti-p53 antibody, ×400.

Figure 7

Panoramic radiograph showing area of mandibular resection with no evidence of recurrence 1 year after surgery.