Prognostic Factors and Treatment Results of High-Grade Osteosarcoma in Norway: A Scope Beyond the “Classical” Patient

Table 2

Relative risk analysis among nonclassical osteosarcoma (OS) patients; primary metastatic disease, nonextremity localisation, and age >40 years.

	Nonclassical OS		Primary metastatic disease			Nonextremity localisation			Age >40 years
	RR^a (95% CI^b)			RR^a (95% CI^b)			RR^a (95% CI^b)			RR^a (95% CI^b)
Axial versus extremity
Extremity			61	1		0			59	1
Axial			23	1.0 (0.7–1.5)	0.953	115			68	3.4 (2.5–4.6)	<0.001
Primary metastatic disease
No			0			89	1		94	1
Yes			84			23	1.0 (0.7–1.5)	0.857	31	1.4 (0.9–2.1)	0.102
Age
≤40 years			53	1		47	1		0
>40 years			31	1.3 (0.9–1.8)	0.109	68	3.1 (2.4–4.1)	<0.001	127
Tumour size
≤10 cm	1		18	1		51	1		48	1
>10 cm	1.1 (0.9–1.4)	0.436	38	1.6 (1.3–2.0)	<0.001	26	0.7 (0.5–1.0)	0.026	42	1.0 (0.8–1.3)	0.870
Duration of symptoms
≤3 months	1		43	1		35	1		41	1
>3 months	1.5 (1.2–1.8)	<0.001	34	0.9 (0.7–1.2)	0.632	61	1.6 (1.3–1.9)	<0.001	65	1.5 (1.2–1.8)	<0.001
Pathologic fracture
No	1		68	1		111	1		102	1
Yes	1.3 (0.8–2.0)	0.364	16	1.5 (0.9–2.4)	0.124	4	0.2 (0.1–0.5)	0.001	25	1.7 (1.1–2.8)	0.025
ALP
Normal	1		18	1		34	1		34	1
Elevated	1.9 (1.4–2.4)	<0.001	46	1.9 (1.5–2.4)	<0.001	43	1.4 (1.1–1.8)	0.017	47	1.5 (1.1–1.9)	0.003
LDH
Normal	1		21	1		43	1		41	1
Elevated	1.3 (1.0–1.6)	0.098	41	1.7 (1.4–2.2)	<0.001	31	0.9 (0.7–1.3)	0.667	37	1.1 (0.8–1.5)	0.473
Histology
Osteoblastic	1		44	1		48	1		51	1
Chondroblastic	1.0 (0.9–1.1)	0.622	8	1.1 (1.0–1.3)	0.124	20	0.9 (0.7–1.0)	0.135	18	0.9 (0.8–1.1)	0.404
Fibroblastic	1.0 (0.9–1.1)	0.816	8	1.0 (0.9–1.2)	0.610	9	1.0 (0.9–1.2)	0.656	13	1.0 (0.8–1.1)	0.530
Other	0.9 (0.8–1.1)	0.423	23	1.1 (0.9–1.4)	0.270	38	0.9 (0.8–1.2)	0.476	44	0.9 (0.7–1.1)	0.220

Relative risk, ^bconfidence interval, value, and ^dnumber of patients.