Multilobular tumor of bone on the forehead of a guinea pig.
Multilobular tumor of bone (MLTB) is an infrequent, slow-growing, bone neoplasm formed predominantly on the head. These tumors can behave as malignant neoplasms clinically and pathologically and can metastasize occasionally. No cases of MLTB in rodents have been reported, to our knowledge. We describe a novel case of an MLTB in a guinea pig. An adult guinea pig had an exophytic mass fixed on the frontal bone, maxilla, and nasal bone. On radiography, the mass had a spherical contour and variable density and was formed on the surface of the cranial bones. The mass was excised surgically. The cut surface was light-yellow to milky-white and had a granular texture with fine fibrous septa. Histologically, the neoplasm had a multilobular pattern, which consisted of many islands of bone and/or cartilage matrix surrounded by small cells and separated by fibrous septa, which closely resembles the equivalent neoplasm in dogs.
['Hatai|Hitoshi|H|https://orcid.org/0000-0002-9063-7616', 'Kido|Nobuhide|N|https://orcid.org/0000-0001-7285-3457', 'Ochiai|Kenji|K|']
D000818:Animals D000836:Animals, Zoo D001859:Bone Neoplasms D005624:Frontal Bone D006168:Guinea Pigs D008437:Maxilla D009295:Nasal Bone D012376:Rodent Diseases
multilobular tumor of bone guinea pigs cranial bones