Diagnostic Challenges in Chondroblastic Maxillary Osteosarcoma: A Case Report

Abstract

The diagnosis of craniofacial osteosarcoma can be quite challenging, and the condition often goes unrecognized for a considerable period of time. In this report, we discuss the case of a 21-year old woman who presented with a one-year history of a small swelling over the left maxillary alveolar ridge. Upon further investigation, the histopathological examination showed high-grade chondroblastic osteosarcoma. The option of four cycles of neoadjuvant chemotherapy regimen preoperatively was chosen, and left inferior maxillectomy was performed along with reconstruction with obturator prosthesis. This case highlights the difficulties encountered in such rare cases of craniofacial osteosarcomas both in terms of the delay in the establishment of the diagnosis as well as management protocol. A high index of suspicion is required in cases of craniofacial osteosarcoma and early surgical resection with adequate safety margins is warranted.

Keywords: chondroblastic; craniofacial; maxillary; osteosarcoma.

Figure 1. Picture of the lesion at the time of the presentation

Irregular mass over the left anterior maxillary alveolar ridge with missed upper lateral incisor was noted (black arrow)

Figure 2. Histopathological examination of the biopsy

The histopathological report of the biopsy revealed fragments of large infiltrative lobules destroying the bone composed of the central hypocellular area (black arrows; 2A and 2C) containing chondroid and osteoid tissue with focal necrosis surrounded by myxoid background (2B). Moreover, the neoplastic cell characteristics are ovoid to spindle with moderately irregular nuclear contours, and contain medium size nucleoli, arranged haphazardly in a myxoid background (2D). Meanwhile, numerous mitotic figures were also seen

Figure 3. CT of the neck

The lesion is seen in the alveolar process of the left maxilla and appears mostly lytic with no material nor sunburst changes while the lesion itself was seen between the left incisor and the left canine (black arrow); meanwhile, the left lateral incisor was not seen CT: computed tomography

Figure 4. MRI of the neck

Left maxillary alveolar ridge osteolytic soft tissue mass of around 3.3 x 1.8 cm extending superiorly to the inferior nasal apparatus (black arrow) MRI: magnetic resonance imaging

Figure 5. Picture of the lesion after neoadjuvant chemotherapy

The response to the chemotherapy was very good and the tumor size shrank substantially (black arrow)

Figure 6. Histopathology examination of tumor section post-therapy using hematoxylin and eosin (H&E) stain

A: high-power examination shows complete tumor necrosis; residual inflammatory cells are seen in the background (H&E; 40x). B: remnants of acellular osteoid, tumor necrosis, and fibrosis (H&E; 40x)