Multilobular tumor of frontal bone in dog: A case report

Abstract

Multilobular tumor of bone (MTB) is an uncommon bone tumor, frequently located on the skull of dogs and rarely on the ribs or pelvis. These neoplasms are slow growing, locally invasive, and have the potential to compress and invade the brain. A 10-years-old mixed breed dog was presented with a history of progressive swelling on head extending more on right side for 3 months. Right eye was bulged out due to this swelling. Radiographic examination revealed presence of soft tissue in growth area whereas bones were not involved. After surgical removal, grossly the neoplasm consisted of multiple, variably sized, grayish-white to yellow nodules separated by collagenous septa of different thickness. Histologically, the tumor was characterized by the presence of multiple lobules containing osteoid and cartilaginous tissue, separated by a net of fibrous septae with extensive calcification. Based upon clinical, radiographical, gross and microscopic findings, the tumor was diagnosed as multilobular tumor involving frontal bone of skull.