flat bone osteosarcoma

Tumors of the flat bone comprised about 10% of osteosarcoma cases. Some cases are secondary osteosarcoma associated with previous radiotherapy.

Patients with a flat bone tumor are significantly older and more likely to present with metastases at diagnosis than extremity tumor.

The proportions of female sex and chondroblastic subtype are higher among flat bone tumors than among extremity tumors.

The 5-year overall survival and event-free survival rates are about 35% and 25%, respectively.

Although age and histologic response to pre-operative chemotherapy are not related to outcome of flat bone tumors, treatment modality influenced the survival.

Patients treated surgically had better outcomes than those treated by another means. Radiation therapy did not appear to be an effective local control measure as surgery.

Treatment outcome of the tumor of the flat bone was worse than extremity tumors.

The locations of tumors :
 pelvis
 mandible
 maxilla
 rib
 spine
 skull
 scapula
 clavicle

References

 Osteosarcomas of flat bones in adolescents and adults. Duffaud F, Digue L, Baciuchka-Palmaro M, Volot F, Perles-Daniel C, Garbe L, Favre R. Cancer. 2000 Jan 15;88(2):324-32. PMID: 10640964 [Free]

 Outcome of flat bone sarcomas (other than Ewing’s) in children and adolescents: a study of 25 cases. Minard-Colin V, Kalifa C, Guinebretiere JM, Brugieres L, Dubousset J, Habrand JL, Vassal G, Hartmann O. Br J Cancer. 2004 Feb 9;90(3):613-9. PMID: 14760373 [Free]