Ewing ’ s sarcoma of the mandible-A rare case report

Journal of Medical Sciences 2011;14(2):68-70 expression for CD99 (MIC2), with characteristic membranous pattern and an IMPRESSION drawn was Conformation of diagnosis of EWINGS SARCOMA. Bone Scan was also advised which revealed Reduced uptake over the body of left mandible without rim of enhanced uptake. No evidence of distal bone involvement. A surgical procedure was performed to resect the malignant tissue with generous surgical margins and to reconstruct the resulting defect. The patient underwent a segmental resection of left side including body of mandible. The bony defect was reconstructed using titanium reconstruction plate (Fig. 4). The postoperative panoramic radiograph revealed a wellaligned reconstruction with intact plating (Fig 5). Adjuant Chemotherapy comprised 20 weeks (3 Cycles) of treatment with a four-drug regimen which were Vincristine [VC],Dactinomycin [AC],Cyclophosphamide [CP] and Doxorubicin [AD] after surgery.

Ewing's sarcoma (ES) is a rare malignant small round cell tumor that primarily affects the skeletal system.It accounts for 4 to10% of all types of bone cancer, with long bones and pelvis being the most common locations.It affects mainly adolescents and young adults and is rarely seen before the age of 5 and after age of 30.Clinically, this tumor has an aggressive behavior characterized by rapid growth and high 1 probability of micrometastasis at diagnosis.

Case Report
An 11-year-old girl visited to Department of Oral & Maxillofacial Surgery Yenepoya dental college and hospital Deralakatte, Mangalore, with the complaint of swelling on the left side of the face (Fig. 1).The swelling started 6 months back which gradually enlarged to present size.On examination, extra orally a diffuse swelling was seen on left side of face which extended superiorly up to ala tragus line, Anteriorly from about 2 cm posterior to commisure of mouth to angle of the mandible.Intra oral examination revealed mixed dentition and swelling extending from left mandibular canine to left mandibular second molar (Fig. 1).
On palpation the swelling was non-tender and hard in consistency.Bi-digital palpation revealed expansion of the buccal plate, no perforation of buccal/lingual cortex and no paresthesia of mucosa or lower lip were seen.Grade III mobility was seen on all the teeth from left mandibular canine to left mandibular second molar, which were non tender on percussion.The intra oral periapical radiograph shows radiolucency near the mandibular teeth (Fig 2).The CT Scan findings revealed: an ill-defined expansile cystic lesion were seen in the body of the mandible on Lt side and thinning & erosion of buccal cortex was also noticed (Fig 2).
The results of hematological and biochemical investigations were within normal limits.Under local expression for CD99 (MIC2), with characteristic membranous pattern and an IMPRESSION drawn was Conformation of diagnosis of EWINGS SARCOMA.Bone Scan was also advised which revealed Reduced uptake over the body of left mandible without rim of enhanced uptake.No evidence of distal bone involvement.A surgical procedure was performed to resect the malignant tissue with generous surgical margins and to reconstruct the resulting defect.The patient underwent a segmental resection of left side including body of mandible.The bony defect was reconstructed using titanium reconstruction plate (Fig. 4).The postoperative panoramic radiograph revealed a wellaligned reconstruction with intact plating (

Discussion
Ewing's sarcoma (ES) is a rare malignant small round cell tumor that primarily affects the skeletal system.It accounts for 4 to10% of all types of bone cancer, with long bones and pelvis being the most common locations.It affects mainly adolescents and young adults and is rarely seen before the age of 5 and after age of 30.Clinically, this tumor has an aggressive behavior characterized by rapid growth and high 1 probability of micrometastasis at diagnosis.ES is a malignant neoplasm that primarily affects long bones of the extremities with nearly 50% of reported cases involving the femur and 2 pelvis.It exhibits a marked predilection for whites and is 3,4 rarely seen among blacks.The majority of the patients affected are between the ages 5 and 20, whereas the disease is distinctly uncommon in individuals before age 5 and after age 30 (braz dent).ES arising from the bones of the head and neck region is exceedingly uncommon.When it occurs in the jaw, 1,2 mandible is more frequently affected than the maxilla.
Ewing's sarcoma is usually sensitive to chemotherapy and radiotherapy.Modern treatments are based on combined Modality of treatment Local therapy (surgery and/or anesthesia, extraction of the mobile teeth left mandibular first molar was performed and the tissue sample obtained through the extraction socket was sent for histopathological examination.(Fig. 3) On microscopic examination, H&E stained sections showed sheets of uniform, small, round cells arranged in diffuse pattern, with indistinct outline, scanty cytoplasm, and well-defined nuclear outline, with round to oval nucleus and inconspicuous nucleoli.Mitotic figures were rare.A diagnosis of malignant small round cell tumor was made based on the above histopathological findings.A panel of immunohistochemical markers namely CD99, CD3, CD20, CHR, MPO, desmin, and SYN were used to rule out other small round cell tumors.Tissue sections showed positive Fig 5).Adjuant Chemotherapy comprised 20 weeks (3 Cycles) of treatment with a four-drug regimen which were Vincristine [VC],Dactinomycin [AC],Cyclophosphamide [CP] and Doxorubicin [AD] after surgery.

FIGURE 2 :
FIGURE 2: The intra oral periapical radiograph showing radiolucency near the mandibular teeth

FIGURE 3 :
FIGURE 3: Microscopic picture under 10x (right panel) and 40x (Left panel) demonstrating the sheets of monotonous, round cells containing single, round to oval nucleus.