Cavasani João P da S, Dos Santos Ícaro G, Garcia Daniela M, Olaya Camilo E B, de Queiroz Adriele A, Néspoli Pedro E B, Souza Marcos de A, Colodel Edson M
Veterinary Pathology Laboratory, Veterinary Hospital-Universidade Federal de Mato Grosso, Cuiabá, Brazil.
Imaging Diagnostic Service, Veterinary Hospital-Universidade Federal de Mato Grosso, Cuiabá, Brazil.
J Vet Diagn Invest. 2025 Mar;37(2):367-370. doi: 10.1177/10406387241313449. Epub 2025 Jan 27.
Ossifying fibroma (OF) is a slow-growing, expansive, and benign fibro-osseous neoplasm that is rare in cattle. It mainly affects the craniofacial bones, especially the mandible. Here, we report 2 cases of mandibular OF in Nelore and mixed-breed steers with enlarged masses in the rostral portion of the mandible. Radiographic analysis of case 1 revealed an oval, lobed mass with the radiopacity of bone tissue that displaced the incisors laterodorsally. Histologically, both masses were composed of a proliferation of spindloid-to-stellate cells, supported by a dense fibrovascular stroma, with bony trabeculae surrounded by stroma and covered by a single layer of osteoblasts. Cellular pleomorphism was low, anisocytosis and anisokaryosis were negligible, and mitotic figures were not observed. The clinical, radiologic, gross, and histologic changes are compatible with OF. The primary differential diagnoses of OF are fibrous dysplasia and osteoma; their differentiation can be difficult. Fibroma, low-grade osteosarcoma, and multilobular sarcoma of bone are also differential diagnoses, with striking features that facilitate their exclusion.
骨化性纤维瘤（OF）是一种生长缓慢、呈膨胀性生长的良性纤维-骨肿瘤，在牛中较为罕见。它主要影响颅面骨，尤其是下颌骨。在此，我们报告2例内洛尔牛和杂交阉公牛下颌骨骨化性纤维瘤病例，在下颌骨前部有肿大肿块。病例1的影像学分析显示一个椭圆形、分叶状肿块，具有骨组织的不透X线性，使切牙向外侧背侧移位。组织学上，两个肿块均由梭形至星状细胞增殖构成，由致密的纤维血管间质支持，有被间质包围并被单层成骨细胞覆盖的骨小梁。细胞多形性低，细胞大小不等和核大小不等可忽略不计，未观察到有丝分裂象。临床、放射学、大体和组织学变化与骨化性纤维瘤相符。骨化性纤维瘤的主要鉴别诊断为纤维发育不良和骨瘤；它们的鉴别可能有困难。纤维瘤、低度骨肉瘤和骨多叶肉瘤也是鉴别诊断对象，其显著特征有助于排除它们。
