Chondrosarcoma

Chondrosarcoma is the most common malignant tumor of the chest wall and sternum. Chondrosarcomas are a variable group of tumors, that all produce neoplastic cartilage. Chondrosarcoma arises from cartilaginous structures and occurs mainly in the anterior chest wall, primarily at the anterior costochondral junctions. Although it is a slow growing tumor, it can become quite large. Chondrosarcomas are usually found in people older than 40 years and are twice as common in men.

Histologically, chondrosarcomas are divided into three grades, Grade I, II, and III. Grade I's histological characteristics include mild hypercellularity, and large vesicular nuclei with small nucleoli. In contrast, features of Grade III include marked hypertrophy, with pleomorphism and the presence of giant tumor cells.

Tumor behavior is associated with tumor grade. Grade I tumors have the best prognosis. Grades II and III have a worse prognosis and are associated with increased rates of metastases, recurrence, and death. Most chondrosarcomas are either Grade I or II. The 5-year survival rates for Grade I, II, and III are 90%, 81%, and 43%, respectively. Metastases are rare in Grade I however, 70% of Grade III have metastases. Tumor size is also associated with prognosis tumors larger than 10 cm are more aggressive than tumors less than 10 cm. The lung and bony skeleton are the two major metastatic sites for chondrosarcoma.

On chest x-rays, these tumors are seen as a mass with destruction of the adjacent bone cortex. A higher degree of radiolucency is associated with a higher tumor grade.

These tumors are best treated by surgical removal of the tumor and a wide margin of normal tissue, up to 5 cm from the tumor and including the underlying pleura and the ribs above and below the lesion. Depending upon the extent of the tumor the manubrium or xiphoid may be spared.