Osteosarcoma of the skull base in a 15-year-old boy.
A 15-year-old boy presented to the Pediatric Otolaryngology Clinic with diplopia and a mass at the medial aspect of the left orbit. The mass had doubled in size over the previous 6 months. He had been previously diagnosed with chronic sinusitis and seasonal allergies. Examination revealed a swelling and a soft-tissue mass in the left supraorbital and ethmoid area. The patient had a full range of eye motion and intact visual acuity.
Flexible fiberoptic nasopharyngoscopy demonstrated a polypoid mass protruding into the left nasal cavity and pedicled medial to the middle turbinate at the left ethmoid region. There was no purulent drainage from the ostiomeatal complex, and the mucosa was otherwise normal. Computed tomography (CT) demonstrated a left frontoethmoid mass with evidence of bone erosion at the skull base and lamina papyracea (figure 1, A). Magnetic resonance imaging (MRI) revealed extension of the mass into the extradural anterior cranial fossa (figure 1, B).
The patient was taken to the operating room for endoscopic biopsy and debulking of the left nasal cavity mass, left maxillary antrostomy, and left total ethmoidectomy. Intraoperatively, a large, left nasal mass consisting of glistening gray tissue was noted. Review of the histology (figure 2, A) suggested a low-grade malignancy, and the diagnosis of a low-grade chondromyxoid neoplasm was made, with a differential diagnosis of chondromyxoid fibroma, chondrosarcoma, and chondroblastic osteosarcoma.
[FIGURE 2 OMITTED]
The patient underwent resection of the tumor via bifrontal craniotomy and epidural exploration. Nasal endoscopy at the completion of the craniotomy showed no evidence of tumor in the left ethmoid or skull base region. The tumor consisted of pink-white cartilaginous tissue admixed with fragments of red-tan bone. Based on histologic examination (figure 2, B), the patient was diagnosed with a grade 3 chondroblastic osteosarcoma. He was referred for chemotherapy and will be closely followed with serial MRIs.
Osteosarcoma is the most common primary malignant tumor of bone, occurring most frequently in the long bones of patients under the age of 20 years. (1) Craniofacial sites account for fewer than 10% of all osteosarcomas, and the most common site in the head and neck is the mandible. (2,3) The mean age at presentation for head and neck osteosarcoma is between 26 and 40 years. (4)
In children, osteosarcomas of the head and neck account for less than 1% of all head and neck malignancies and usually arise as secondary tumors after radiation therapy or chemotherapy. (2) Other predisposing factors include retinoblastoma and Li-Fraumeni syndrome) Primary osteosarcoma of the craniofacial bones in children is even less common and typically presents as an expanding, painless swelling of 6 months' duration. (2)
Pathologically, these tumors range from 1 to 10 cm in size and demonstrate destruction of bone and surrounding tissues. (2) A review of 22 cases of pediatric primary head and neck osteosarcoma showed a mean age at presentation of 12.2 years, with no gender predilection. (2) Of these 22 cases, 2 involved osteosarcoma of the sphenoid sinus, while the rest were maxillomandibular in origin.
Histologically, osteosarcoma is characterized by the production of osteoid by the tumor cells. Chondroblastic osteosarcoma is a histologic subclassification of osteosarcoma in which the tumor cells predominantly produce a chondroid rather than osteoid matrix. (1,5) The presence of this subtype makes our case even more unusual.
Osteosarcoma of the craniofacial bones can have extensive local involvement but rarely metastasizes. Primary management is with surgical excision with negative margins, although this may be difficult in extragnathic sites. The 5- and 10-year survival rates for pediatric primary osteosarcoma of the head and neck have been reported as 63 and 52%. (2)
Although the role of adjuvant therapy has not yet been proven effective in osteosarcoma of the head and neck in children, it is frequently recommended because of the tumor's poor prognosis. (6) Local recurrences are common and typically occur within 1 year of the original diagnosis. They can be treated with additional surgery and adjuvant therapy. (2)
(1.) Kumar V, Abbas AK, Fausto N (eds). Robbins and Cotran Pathologic Basis of Disease, 7th ed. Philadelphia: Elsevier Saunders; 2005:1292-1301.
(2.) Gadwal SR, Gannon FH, Fanburg-Smith IC, et al. Primary osteosarcoma of the head and neck in pediatric patients: A clinicopathologic study of 22 cases with a review of the literature. Cancer 2001;91(3):598-605.
(3.) Park HR, Min SK, Cho HD, et al. Osteosarcoma of the ethmoid sinus. Skeletal Radio12004;33(5):291-4.
(4.) Ha PK, Eisele DW, Frassica FJ, et al. Osteosarcoma of the head and neck: A review of the Johns Hopkins experience. Laryngoscope 1999;109(6):964-9.
(5.) Blakely LJ, Trent JC, Shreyaskumar P. "Chapter 33: Soft Tissue and Bone Sarcomas." Kantarjian HM, Wolff RA, Koller CA: MD Anderson Manual of Medical Oncology. McGraw-Hill Companies, 2006. 879-902.
(6.) Maes P, Brichard B, Vermylen C, et al. Primary and secondary osteosarcoma of the face: A rare childhood malignancy. Med Pediatr Oncol 1998;30(3):170-4.
Gretchen M. Oakley, BA; Dary J. Costa, MD; Ron B. Mitchell, MD; Cirilo Sotelo, MD
From Saint Louis University School of Medicine (Ms. Oakley); the Department of Otolaryngology-Head and Neck Surgery, Saint Louis University School of Medicine (Dr. Costa); the Department of Otolaryngology-Head and Neck Surgery, UT Southwestern Medical Center, Children's Medical Center Dallas, Dallas, Texas (Dr. Mitchell); and the Department of Pathology (Dr. Sotelo), SSM Cardinal Glennon Children's Medical Center, St. Louis.
|Printer friendly Cite/link Email Feedback|
|Title Annotation:||PEDIATRIC OTOLARYNGOLOGY CLINIC|
|Author:||Oakley, Gretchen M.; Costa, Dary J.; Mitchell, Ron B.; Sotelo, Cirilo|
|Publication:||Ear, Nose and Throat Journal|
|Article Type:||Case study|
|Date:||Oct 1, 2011|
|Previous Article:||A large cervical osteophyte presenting as an oropharyngeal mass.|
|Next Article:||A purely intracanalicular cochlear schwannoma presenting with progressive hearing loss.|