Table V.

Association between surgery type and survival outcome in patients <25 years of age with osteosarcoma between 1973 and 2012, according to stage and grade.

	Stage (n=1,915)			Grade (n=1,439)
Variables	Localized	Regional	Distant	Well	Moderately	Poorly	Undifferentiated	All (n=1977)
Number
No surgery	53	53	107	2	4	42	88	244
Local excision	98	75	29	16	13	48	78	208
Radical excision	396	504	163	25	53	229	492	1076
Amputation	101	235	101	8	12	91	238	449
Order of outcome
Best	2	2	3	1	3	2	2	2
Relatively good	3	3	2	3	2	3	3	3
Relatively poor	4	4	4	2	1	4	4	4
Worst	1	1	1	4	4	1	1	1
Significance
No surgery vs. local excision	a0.031	aP<0.001	a0.011	0.622	0.523	a0.005	aP<0.001	aP<0.001
No surgery vs. radical excision	a0.046	aP<0.001	aP<0.001	0.724	0.113	aP<0.001	aP<0.001	aP<0.001
No surgery vs. amputation	0.478	aP<0.001	a0.001	0.385	0.994	a0.033	aP<0.001	aP<0.001
Local excision vs. radical excision	0.469	0.557	0.202	0.505	0.393	0.682	0.576	0.462
Local excision vs. amputation	0.092	0.243	0.589	a0.037	0.358	0.165	0.087	a0.001
Radical excision vs. amputation	0.139	0.263	a0.002	a0.006	a0.014	0.081	a0.042	aP<0.001

^aStatistically significant. P<0.05 was considered to indicate statistically significant difference. P-values were calculated by log-rank tests. n, number.