OOOO ABSTRACTS

Volume 117, Number 2 Abstracts e163

PE-160 - HIGH-GRADE OSTEOBLASTIC OSTEOSAR-COMA OF THE MANDIBLE: CASE REPORT. ANDREALUSVARGHI WITZEL, SHEYLA BATISTA BOLOGNA,THAÍS BORGUEZAN NUNES, JESSICA ELEN DA SILVACOSTA, JULIANA SEO, DECIO DOS SANTOS PINTOJUNIOR, SILVIA VANESSA LOURENÇO. DEPARTMENTOF STOMATOLOGY, SCHOOL OF DENTISTRY, USP ANDCLINICS HOSPITAL, SCHOOL OF MEDICINE. USP.

Osteosarcoma is the most common bone malignancy andaccounts for 20% of all sarcomas, but rarely affects the jaws.Young man, 16, came to the CDO-FOUSP complaining of aswollen face. Clinical examination showed a deformed hemifaceand enlarged buccal and lingual cortical aspect of the mandibularright side. Incisional biopsy revealed a mesenchymal neoplasm.The case was referred to HCFMUSP for investigation andmanagement. Imaging revealed an extensive osteolytic lesionwith cortical destruction in the angle of the jaw. Hemi-mandibulectomy and microsurgical flap reconstruction weredone. Histopathological examination of the specimen confirmedthe diagnosis of high-grade osteoblastic osteosarcoma. The pa-tient completed the cycle of adjuvant chemotherapy and 6months of follow-up. Osteosarcomas have varied clinical andhistopathological findings. Early surgical resection of the lesionis necessary to avoid recurrent and metastatic complications ofthe tumor.

PE-161 - HIGHLY AGGRESSIVE MUCOEPIDERMOIDCARCINOMA: CASE REPORT. GUSTAVO GOMESAGRIPINO, ROBECI ALVES MACEDO FILHO, SANDRAAPARECIDA MARINHO, FRANCISCO JADSON LIMA,DALIANA QUEIROGA DE CASTRO GOMES, HÉBELCAVALCANTI GALVÃO, MANUEL ANTONIO GORDÓN-NÚÑEZ. UNIVERSIDADE ESTADUAL DA PARAÍBA.

Fast-growing tumors are highly suggestive of malignancy insalivary glands. Man, 85, visited the Dentistry Extension Pro-gram of the Universidade Estadual da Paraíba, Brazil, requestingextraction of tooth #18 and complaining of increased volume ofthe hard palate. Clinical examination revealed swelling (painlessupon palpation) throughout the maxilla and extending to themaxillary sinuses and eye socket. Imaging revealed extensivebone destruction affecting the maxillary sinuses and floor of theeye socket, indicating aggressive malignancy. After biopsy, theanatomopathological analysis led to the diagnosis of high-grademucoepidermoid carcinoma. The patient was sent for treatment,which consisted of tumor and ocular globe excision, followed byradiotherapy and is currently in dental follow up to controltoxicity, which should culminate in rehabilitation with an oral-maxillofacial prosthesis. Urgency and immediate adherence totreatment were essential to the good prognosis in the presentcase.

PE-162 - HISTOPATHOLOGICAL FEATURES OF THEGNATHIC OSTEOSARCOMA: CASE REPORT. SANDRALÚCIA VENTORIN VON ZEIDLER, MARCELLA SOL,JÚLIA ALMENARA RIBEIRO VIEIRA, MARIANE GARCIAOLIVEIRA, JOSÉ ROBERTO VASCONCELOS DEPODESTÁ, RENATA SCARPAT CARETA, SONIA ALVESGOUVEA. FEDERAL UNIVERSITY OF ESPÍRITO SANTO,VITORIA, ES.

Gnathic osteosarcoma is a rare condition that presentsconsiderable histopathologic variability. The microscopic essen-tial criterion for diagnosis is the direct production of osteoid by

malignant mesenchymal cells. However, in some cases, osteoidproduction can be difficult to diagnose. Young man, 18, devel-oped significant swelling in the jaw between teeth #34 and#36. Microscopic analysis confirmed malignant mesenchymalneoplasm, suggesting epithelioid osteosarcoma classic pattern,grade 1, as classified by the Fédération Nationale des Centres deLutte Contre le Cancer-FNCLCC. The immunohistochemicalpanel using S-100 protein, vimentin, EMA, pancytokeratin AE1/AE3, antigen Melan A, HMB-45, CD68, and cell proliferationantigen Ki-67 helped to confirm the diagnosis. Treatment con-sisted of segmental mandibulectomy and adjuvant chemotherapy.The patient has been followed up for 3 years without recurrence.The diagnosis of gnathic osteosarcoma is always challengingbecause of its rarity and complexity.

PE-163 - HISTOPLASMOSIS ORAL MANIFESTATION INAIDS PATIENT. MARCIA RODRIGUES GORISCH,ROSANA MARA GIORDANO DE BARROS, EDUARDOGIORDANO DE BARROS, SILVIA ROBERTA CIESLAK.FACULDADE DE ODONTOLOGIA DA UFMS.

Histoplamosis is the most common systemic fungal disease.In endemic areas it manifests as an opportunistic infection thatfrequently accompanies the diagnosis of acquired immunodefi-ciency syndrome (AIDS). Patient, 20, contacted the Faodo/UFMSoral diagnostic service with ulcerative lesion in the palate. His-topathological analysis using PAS staining evidenced the pres-ence of fungi associated with macrophagic cells. The use ofimmunohistochemical techniques may also be useful becausethey are highly specific and rapid, replacing culture techniquesthat take 2 to 3 weeks for completion. This aids in the earlydiagnosis and immediate treatment of AIDS patients. In histo-plamosis the cutaneous and oral mucosa involvement in immu-nosuppressed patients occurs as a result of the hematogenicdissemination. Its occurrence ranges from 1.4% to 85%. In Brazilno data were found on the cutaneous and oral mucosa manifes-tation frequency of histoplamosis associated with AIDS.

PE-164 - HYALINE RING GRANULOMAS IN DENTIG-EROUS CYST: RARE CASE REPORT. HELLEN BANDEIRADE PONTES SANTOS, ROBERIA LÚCIA DE QUEIROZFIGUEIREDO, JOZINETE VIEIRA PEREIRA, PATRÍCIAMEIRA BENTO, DANIELA PITA DE MELO, POLLIANNAMUNIZ ALVES, CASSIANO FRANCISCO WEEGENONAKA. UNIVERSIDADE ESTADUAL DA PARAÍBA.

Hyaline ring granulomas (HRGs) are characterized by hya-line rings or ovoid homogeneous/fibrillar hyaline masses lyingwithin fibrous connective tissue. These contain variable numbersof inflammatory cells and multinucleated giant cells. These his-topathological findings are rare in dentigerous cysts. Boy, 7, wasreferred for evaluation of a soft, painless swelling in the anteriorleft mandible. The deciduous canine was nonvital, and radio-graphic examination showed a unilocular radiolucency associatedwith the crown of the unerupted permanent canine. The pre-liminary diagnosis of dentigerous cyst prompted an incisionalbiopsy. Histopathological examination revealed a cystic cavitylined by a thin, nonkeratinized stratified squamous epitheliumpresenting areas of hyperplasia, spongiosis, and exocytosis. In thefibrous capsule, small ovoid homogeneous/fibrillar hyalinemasses were associated with multinucleated giant cells, compat-ible with a diagnosis of HRGs. The definitive diagnosis wasinflamed dentigerous cyst, which was treated with marsupializa-tion of the lesion. The patient remains under close follow-up.