Table 2.

Baseline information of subjects and univariate analysis of prognostic factors.

Prognostic factor		Case (%)	Median survival time	Survival time (95%CI)	P
Age	<60	83 (49.4)	14	15.06 (13.46–16.67)	0.479
	≥60	85 (50.6)	13	14.09 (12.36–15.81)
Gender	Male	102 (60.7)	14	15.15 (13.64–16.69)	0.201
	Female	66 (39.3)	13	13.67 (11.82–15.52)
Pathologic types*	Adenocarcinoma	74 (44.0)	9	11.83 (10.21–13.46)	<0.001
	Squamous cell carcinoma	45 (26.8)	17	18.47 (16.25–20.68)
	SCLC	33 (19.6)	13	14.93 (12.21–17.66)
	Large cell carcinoma	16 (9.6)	15	15.25 (12.34–18.16)
Number of primary lesions	Single	119 (70.8)	13	14.49 (13.07–15.91)	0.970
	Multiple	49 (29.2)	13	14.77 (12.66–16.88)
Number of bone metastases*	Single	42 (25.0)	18	19.98 (17.80–22.16)	<0.001
	Multiple	126 (75.0)	12	12.78 (11.53–14.03)
Clinical stage*	I	17 (10.1)	20	20.23 (17.01–23.44)	<0.001
	II	44 (26.2)	16	17.75 (15.65–19.86)
	III	70 (41.7)	13	14.18 (12.49–15.88)
	IV	37 (22.0)	7	8.80 (6.93–10.67)
ECOG scores*	0–1	47 (28.0)	16	17.57 (15.42–19.71)	0.008
	2–4	121 (72.0)	12	13.38 (12.02–14.73)
Time after diagnosis of bone metastases (months)	≤4	110 (65.5)	13	14.20 (12.77–15.62)	0.363
	>4	58 (34.5)	13	15.38 (13.26–17.50)
Chemotherapy	Yes	123 (73.2)	13	14.31 (12.98–15.64)	0.443
	No	45 (26.8)	14	15.24 (12.77–17.71)
Radiotherapy	Yes	128 (76.2)	14	14.61 (13.27–15.96)	0.993
	No	40 (23.8)	13	14.40 (11.96–16.83)
Bisphosphonate therapy	Yes	139 (82.7)	13	1423 (12.93–15.53)	0.272
	No	29 (17.3)	15	16.25 (13.48–19.02)
Serum ALP(U/L)*	<140	55 (32.7)	17	18.34 (16.22–20.45)	<0.001
	≥140	113 (67.3)	12	12.71 (11.43–13.99)
Serum Ca+ (mmol/L)	<2.4	44 (26.2)	13	14.82 (12.48–17.16)	0.970
	≥2.4	124 (73.8)	14	14.47 (13.10–15.83)

^*Significant differences. Survival time and median survival time were performed by Kaplan-Meier; and P value is obtained by Log-Rank test.