What is a typical finding on physical examination in a case of osteosarcoma?

In cases of osteosarcoma, a large and tender mass is a hallmark finding during the physical examination. Osteosarcoma primarily affects the metaphysis of long bones, often around the knee or the shoulder. The tumor typically presents as a palpable and progressively enlarging mass, reflecting the underlying bone lesion. The mass is often associated with pain that can be severe and may worsen at night or with activity, which along with tenderness is indicative of the aggressive nature of this bone cancer.

Soft tissue swelling may be present to some degree, but it is primarily the mass that is recognizable and significant in the context of osteosarcoma. Color changes in the skin are not specific indicators for osteosarcoma and arise in other conditions, while systemic symptoms like fever and chills are more suggestive of infections or other systemic diseases rather than a primary malignant bone tumor. Thus, the presence of a large and tender mass is most characteristic of osteosarcoma, making it the correct answer in this context.