Prognostic Factors in Osteosarcoma

Parameter

Significance

T classification (TNM)

T1 (confined within cortex) better than T2 (extends beyond the cortex)

histologic grade

well (G1) and moderately differentiated (G2) better than poorly (G3) or undifferentiated (G4)

location

resectable better than unresectable

size of primary tumor

<= 15 cm better than > 15 cm

serum levels alkaline phosphatase

normal serum levels better than elevated levels

serum levels of LDH

normal serum levels better than elevated levels

extent

localized better than metastatic

metatastic sites

solitary lung metastasis better than multiple

bone or liver metastases much worse than lung

histologic response to preoperative chemotherapy

> 90% necrosis (good response) is better than <= 90%