Table 1.

Survival estimates by patient- and tumour-related factors of 83 registered osteosarcoma patients with primary multi-systemic metastases.

				Overall Survival
	Patients		%	1-Year		2-Year		5-Year
				Rate	SE	Rate	SE	Rate	SE	p *
All eligible patients		83	100	0.540	0.056	0.232	0.049	0.087	0.033
Age at initial diagnosis, years
	<14.8	41	49	0.455	0.079	0.278	0.071	0.111	0.052	0.960
	≥14.8	42	51	0.627	0.076	0.177	0.064	0.059	0.040
Sex
	Female	40	48	0.479	0.081	0.160	0.060	0.096	0.050	0.311
	Male	43	52	0.597	0.076	0.304	0.074	0.083	0.046
Duration of pain until initial diagnosis
	<47 days	35	50	0.460	0.087	0.246	0.075	0.140	0.063	0.773
	≥47 days	35	50	0.591	0.084	0.217	0.076	0.072	0.049
	No pain/unknown	13
Duration of swelling until initial diagnosis
	<38 days	27	50	0.622	0.095	0.311	0.091	0.133	0.070	0.559
	≥38 days	27	50	0.542	0.098	0.152	0.079	0.051	0.049
	No swelling/unknown	29
Pathological fracture at initial diagnosis
	No	70	89	0.537	0.060	0.248	0.053	0.099	0.038	0.402
	Yes	9	11	0.292	0.173	0.146	0.135	0.000	0.000
	Unknown	4
Alkaline phosphatase before start of chemotherapy
	Normal	12	18	0.750	0.125	0.536	0.156	0.214	0.133	0.019
	Elevated	56	82	0.456	0.068	0.152	0.049	0.057	0.032
	Unknown	15
Lactate dehydrogenase before start of chemotherapy
	Normal	14	22	0.929	0.069	0.314	0.129	0.079	0.075	0.078
	Elevated	50	78	0.388	0.071	0.186	0.058	0.093	0.044
	Unknown	19
Primary tumour site
	Extremity	72	88	0.503	0.060	0.241	0.053	0.069	0.033	0.525
	Trunk	10	12	0.778	0.139	0.111	0.105	0.111	0.105
	Head and neck	1		1.000		1.000		1.000
Tumour size at initial diagnosis (limb only)
	Small (<1/3 of the involved bone’s length)	23	42	0.595	0.104	0.250	0.095	0.062	0.059	0.364
	Large (≥1/3 of the involved bone’s length)	32	58	0.488	0.090	0.199	0.076	0.079	0.053
	Other site/unknown	28
Number of metastatic sites involved at initial diagnosis
	Two	57	70	0.529	0.066	0.232	0.058	0.077	0.037	0.839
	Three	25	30	0.438	0.103	0.246	0.093	0.123	0.077
	Unknown	1
Metastatic sites involved at initial diagnosis
	Lung and bone	42	74	0.468	0.078	0.133	0.055	0.027	0.026	0.005
	Lung and other	13	23	0.923	0.074	0.508	0.144	0.169	0.109
	Bone and other	2	4	1.000		0.500	0.354	0.500	0.354
	Other and other	0	0
	Three sites/unknown	26
Pulmonary metastases at initial diagnosis
	No	2	2	1.000		0.500	0.354	0.500	0.354	0.428
	Yes	81	98	0.529	0.056	0.225	0.049	0.075	0.032
Laterality of pulmonary metastases
	Unilateral	4	5	0.750	0.217	0.500	0.250	0.000	0.000	0.637
	Bilateral	71	95	0.519	0.061	0.215	0.052	0.083	0.035
	None/unknown	8
Pleural effusion at initial diagnosis
	No	35	80	0.441	0.085	0.173	0.069	0.069	0.047	0.010
	Yes	9	20	0.222	0.139	0.000	0.000	0.000	0.000
	Unknown	39
Bone metastases at initial diagnosis
	No	13	16	0.923	0.074	0.508	0.144	0.169	0.109	0.010
	Yes	69	84	0.473	0.061	0.182	0.049	0.073	0.034
	Unknown	1
Number of bone metastases at initial diagnosis
	One	14	21	0.701	0.126	0.390	0.136	0.156	0.101	0.028
	At least two	53	79	0.393	0.068	0.133	0.051	0.053	0.035
	None/unknown	16
Other metastases at initial diagnosis
	No	42	51	0.468	0.078	0.133	0.055	0.027	0.026	0.018
	Yes	41	49	0.617	0.078	0.338	0.078	0.154	0.062
Number of other metastases at initial diagnosis
	One	17	43	0.765	0.103	0.499	0.128	0.166	0.105	0.476
	At least two	23	58	0.525	0.109	0.239	0.093	0.143	0.077
	None/unknown	43
Complete surgical resection assessed as feasible at initial diagnosis
	No	45	74	0.387	0.073	0.137	0.052	0.091	0.043	0.010
	Yes	16	26	0.938	0.061	0.554	0.138	0.092	0.087
	Unknown	22

* p-value, log-rank test.