[Fibroblastic osteosarcoma in mandible: a rare case report and review of literature]

Osteosarcoma is a malignancy of mesenchymal cells that have the ability to produce Osteoid or immature bone. Osteosarcoma of the jaw is uncommon and represents 6-8% of all osteosarcomas. This tumor occurs most often in the third and fourth decades of life, which is 10-15 years older than the mean age for Osteosarcomas of the long bones. The Maxilla and Mandible are involved with a boot equal frequency and a slight male predominance, is noted. Mandibular tumors arise more frequently in the posterior body and horizontal ramus. Maxillary lesions are discovered more commonly in the alveolar ridge, sinus floor and palate. This article is a report of fibroblastic Osteosarcoma in the mandible of a 35 years old man that has been referred to pathology Department of Shahid Beheshti dental school. The specific characteristic of this case, is its histologic features, because fibioblastic Osteosarcoma is rare in jaws and most cases are chondroblastic Osteosarcoma

[Evaluation of expression and intensity of cytiokeratin-10 and 19 in odontogenic keratocyst [OKC] with immunohistochemical staining and comparing it with dentigerous cyst and dental follicle]

Odontogenic keratocyst [OKC] and dentigerous cyst are two most common developmental odontogenic cysts involving jaws. OKC has a high growth potential in contrast to its minor clinical manifestation. It has also a high degree of recurrence rate. The purpose of this study was to diagnose the OKC and dentigerous cysts and also differentiate them based on their immunohistochemical criteria. To provide the materials for this research, we preliminarely reviewed the records of the patients referred to pathology lab of shahid Beheshti Dental College between March 1999 and March 2003 and 60 paraffin-embedded biopsies [20 OKC, 20 dentigerous cysts and 20 dental follicles] were selected. Then immunhistochemical staining was applied to identify cytokeratin-10 [CK-10] and cytokeratin-19 [CK-19] and their conditions, as well. The expression of CK-10, CK-19 are seen in OKC and dentigerous cyst. CK-10 was found more in OKC, along with CK-19 in dentigerous cyst. The expression of these cytokeratins was more in upper half of the epithelial lining of these cysts. One of the dental follicles expressed CK-19, but not CK-10. CK-10 is more specific for OKC as well as CK-19 for dentigerous cyst. These cytokeratins are usually seen in the upper layers of the cyst lining. If an expression of cytokeratin-19 is found in a dental follicle, it may correspond the cystic transformation of the latter one