Monday, July 13, 2009

Ewing’s sarcoma of the mandible: Radiographic features with emphasis on magnetic resonance appearance

LUTHERAN MEDICAL CENTER
Dental Residency Program
Literature Review Form

Resident: Boboia Date: 7/24/09
Article title: Ewing’s sarcoma of the mandible: Radiographic features with emphasis on magnetic resonance appearance
Author(s): Gorospe et al
Journal: Oral Surgery, Oral Medicine, Oral Path., Oral Radio., Endo
Volume #; Number; Page #s): 91: 6, 729-734
Month / Year: June 2001
Major topic: Ewings sarcoma / Imaging using MRI
Minor topic(s):
Type of Article: Case Presentation
Main Purpose: Review the radiologic features of an ES lesion emphasizing its appearance on MRI
Review of the Case: A 12 y/o female presents with facial swelling x 7 days. Once a diagnosis of ES with extension into the surrounding soft tissues was made, a chemotherapy protocol was commenced. Progress was evaluated using MRI after the second round of chemo. Due to progression of the tumor, radiotherapy was added to the treatment. After the 10th chemotherapy cycle the patient underwent an autologous bone marrow transplantation. The patient was discharged 15 days s/p transplantation. A new MRI revealed a decrease in tumor volume. All lab data normalized 40 days after transplantation. Clinical follow-up revealed the patient is alive and symptom free with no evidence of recurrence or distant metastases. Labs were normal 36 months after diagnosis.
Review of ES: : ES was first described in 1921. This lesion is thought to have neuroectodermal origin, exhibiting some histological similarities as these tumors. This is the second most common primary malignant bone tumor in children and adolescents. 80% of cases occur in the first 2 decades of life with a 2:1 male to female ratio. These lesions account for 4-15% of all primary bone tumors and 1% of all malignant tumors in children. 2/3 of all cases appear in the lower skeleton with a predisposition for long bones of the extremities and the pelvis; the involvement of the facial skeleton is very rare (3%). When the facial skeleton is involved, the mandible is the most commonly affected bone. ES is composed of small round cells with oval / round nuclei and scarce clear cytoplasm arranged in sheets. Differential diagnosis should consider osteosarcoma, lymphoma, neuroblastoma, and other neuroectodermal tumors. Swelling in the invoved area and pain are common symptoms for mandibular ES. Traditional treatment includes surgical excision and local irradiation. Recently chemotherapy and radiotherapy have dramatically improved long term survival rates. Surgery is justified only if tumor control and preservation of function are guaranteed. In this case surgery was not done due to the extension of the tumor into the surrounding tissues as well as pulmonary metastases.
Imaging: Plain radiographs are the first tool for determining presence of bone lesions; ES presents as a lytic, permeative, poorly defined lesion. CT scan provides better visualization yet similar information as that obtained from radiographs. It also provides more detailed information regarding the bone marrow extension of the primary tumor. MRI is the gold standard of imaging the extension of the primary tumor (it therefore remains the method of choice for tumor staging) as well as determining the effects of therapy.
Summary of conclusions: MRI is the diagnostic tool of choice in the local staging of ES and is an imaging technique of great value in monitoring the effects of chemotherapy
Assessment of article: Fair review of ES. MRI has routinely been used to stage and follow the progress of ES tumors for some time now (not exactly front page news).

No comments:

Post a Comment