Osteosarcoma

Allison Zwingenberger

University of California Davis

This work is licensed under the Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 United States License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-nd/3.0/us/ or send a letter to Creative Commons, 171 Second Street, Suite 300, San Francisco, California, 94105, USA.
Publication Date: 2007-08-13

History

8 year old female neutered St. Bernard with non weight-bearing lameness and firm swelling on the distal tibia of the right hind limb.

Findings

There is a large, expansile, destructive osseous lesion of the distal right tibia with cortical destruction most severe at the caudal and medial margins. There is also mild, irregular periosteal proliferation and soft tissue thickening at the site.

Differentials

Primary bone tumor

• osteosarcoma
• chondrosarcoma
• fibrosarcoma
• hemangiosarcoma
• liposarcoma

Diagnosis

Osteosarcoma

Discussion

This lesion is characteristic of a primary bone tumor. The location and expansile, destructive pattern are features to look for. A fungal osteomyelitis would tend to have more productive bone, and is often multifocal. Osteosarcoma is most likely in this case.