OsteosarcomaDz

Synonyms: Osteogenic sarcoma.

ICD-9 Code: M9180/3.

ICD-10 Code: c40-C41

Definition: Osteosarcoma is a primary bone malignancy characterized by proliferating sarcomatous spindle cells producing osteoid.

Demographics: The incidence approaches two cases per million population. Osteosarcoma predominantly affects children and adolescents. Males are more commonly afflicted than females. Adults with Paget’s disease (<1%) or those who have had previous bone irradiation are also at increased risk.

Cardinal Findings: Intermittent pain progresses to chronic, deep pain in an affected extremity. Firm, fusiform swelling of an extremity is accompanied by loss of movement in the adjacent joint. Primary tumor develops in the metaphyseal region of long bone. Approximately half of cases involve the distal femur or proximal tibia. The lung is the most common site of metastasis.

Keys to Diagnosis: Nonarticular extremity pain and swelling in an older child should suggest osteosarcoma.

Imaging: Plain radiography shows mixed sclerotic and lytic lesions with periosteal reaction and soft tissue mass. Occasionally a “sunburst” pattern of new bone formation is seen.

Therapy: Amputation or limb-sparing surgery with pre- and postoperative chemotherapy is used most commonly. Osteosarcoma is radioresistant.

Prognosis: Despite an aggressive disease course with a high risk of metastasis, a 5-year relapse-free survival rate as high as 40% to 80% has been reported in some series. Poor prognosis occurs with axial involvement, lesions larger than 15 cm, marked elevations of lactate dehydrogenase and alkaline phosphatase, in males, and those younger than 10 years of age. The best prognosis occurs with proximal tibial involvement, age older than 20 years, and in females.

BIBLIOGRAPHY

Clark CR, Bonfiglio M. Orthopaedics: essentials of diagnosis and treatment. New York: Churchill