Primary Jaw Tumors in Children

Metastatic Biphasic Primitive Tumor in the Mandible of a Child

Pediatric mandibular tumors present an aggressive biological behavior and difficult diagnosis. A wide range of odontogenic and nonodontogenic tumors comprise the spectrum of these lesions. We report a case of a 1-year-old male child patient showing facial asymmetry symptomatic of an expansive lesion extending throughout the body and ramus of the left hemimandible with a diameter of 8 cm. The histopathological report suggested a high-grade mucoepidermoid carcinoma (MEC), recommending further immunohistochemical investigation of the ectomesenchymal or neuroectodermal origin of the tumor cells. The patient evolved with extensive bilateral pleural effusion followed by metastasis in the middle third of the right humerus, and died 2 months after the first biopsy procedure by acute renal failure with tubular necrosis, before a final inconclusive immunohistochemical report was reached. The lack of resources for less-favored regions of Brazil impairs rapid biomolecular examinations such as immunohistochemical resulting in delay of appropriate therapeutic procedures.

Craniofacial disorders

The complexity of the craniofacial patient mandates the cooperation of a multidisciplinary team that can systematically evaluate each individual and ensure that a protocol-driven pathway is undertaken for the best patient care. Oral and maxillofacial surgeons contribute to surgical care in this setting with specific knowledge of growth and development of the face. This enables optimum timing for early skeletal correction where appropriate, and definitive surgery following the cessation of growth to maximize function and aesthetics. This chapter will describe the major principles in managing patients with specific craniofacial anomalies and provide examples of the outcomes possible.

Pediatric mandibular metastasis: A rare finding of neuroblastoma

We present a case of metastatic neuroblastoma to the mandible in an 11-month-old patient presenting with worsening right-sided proptosis and scalp swelling after a fall 2 weeks prior. Initial evaluation with computed tomography of the head demonstrated soft tissue masses centered at the right sphenoid and right mandible. These masses proved to be metastatic lesions from an intra-abdominal neuroblastoma. Review of the literature revealed 20 cases of neuroblastoma metastasis to the mandible over the past 70 years. To our knowledge, our patient is the youngest reported case with asymptomatic mandibular metastasis related to neuroblastoma and the first to be characterized with magnetic resonance imaging.

Clinicopathological Characteristics and Prognosis of Ossifying Fibroma in the Jaws of Children: A Retrospective Study

BACKGROUND: Ossifying fibroma in the jaws is a benign tumor and easily recurs in children, of which the treatment methods and prognosis still remain controversial. In this study, we aimed to review the clinicopathological characteristics, treatment, and prognosis of ossifying fibroma in the jaws of children, and offer recommendations for clinical decision-making. METHODS: A retrospective study was carried out on patients below the age of 18 years with ossifying fibroma in the jaws. Patients with complete clinical, pathological, and radiological records were included and followed-up. RESULTS: Sixty-three cases were collected with a preliminary search. After screening, fifty patients were included for general information analysis, of which forty-two patients were included in the recurrence analysis. Twelve patients showed a relapse, with a recurrence rate of 28.6% (12/42). The recurrence rates in cases with different surgical approaches and different X-ray boundaries were statistically different. Besides, twenty-three patients underwent reconstruction by free tissue grafting and the success rate was 96% (22/23). CONCLUSIONS: There was significant difference in the recurrence rates among different X-ray manifestations and surgical methods. An extended resection and reconstruction with free tissue grafting was a reliable method with a 96% success rate.

Chromosome 12 long arm rearrangement covering MDM2 and RASAL1 is associated with aggressive craniofacial juvenile ossifying fibroma and extracranial psammomatoid fibro-osseous lesions

To evaluate the diagnostic value of MDM2 status in craniofacial fibro-osseous lesions, we investigated MDM2 expression by immunohistochemistry and analyzed MDM2 amplification by qPCR in 30 cases of ossifying fibroma (including 13 cases of the juvenile variant) and 17 cases of fibrous dysplasia. Two cases of uncommon extragnathic psammomatoid fibrous dysplasia and a mixed control group of 15 cases of low-grade osteosarcoma and 15 cases of well-differentiated/dedifferentiated liposarcoma were included. MDM2 amplification was found in 33% of ossifying fibromas (peak of 69% for the juvenile variant) and in 12% of fibrous dysplasia, in none of which was MDM2 overexpressed. All control cases exhibited MDM2 amplification and overexpression. To investigate possible polysomy of chromosome 12, we studied RASAL1 amplification, a gene telomeric to MDM2 on the long arm of chromosome 12. RASAL1 amplification was reported in all benign fibro-osseous lesions exhibiting MDM2 amplification but not in controls. Simultaneous amplification of these two genes was significantly higher in juvenile ossifying fibromas compared with fibrous dysplasia (P=0.004), non-juvenile ossifying fibromas (P=0.001), and all other benign craniofacial fibro-osseous lesions combined (P=0.0001). Of the nine cases of juvenile ossifying fibroma exhibiting amplification, three were locally invasive and four were recurrent, suggesting aggressive disease. The two cases of extragnathic psammomatoid fibrous dysplasia also showed MDM2 and RASAL1 amplification with no MDM2 overexpression. This large chromosome 12 rearrangement, spanning MDM2 and RASAL1, is the first recurrent molecular abnormality to be reported in juvenile ossifying fibroma. It may represent both a molecular diagnostic marker and a characteristic of more aggressive forms with a higher risk of recurrence. Finally, the presence of this rearrangement in extragnathic psammomatoid fibro-osseous lesions mimicking ossifying fibromas might reflect a common molecular pathway in their pathogenesis and calls into question the classification of such lesions within fibrous dysplasia.