Prognostic Significance of Serum Alkaline Phosphatase Level in Osteosarcoma: A Meta-Analysis of Published Data

Table 1

Main characteristics and results of the eligible studies for evaluation of overall survival.

Study; (author/year)	Country	Number of patients	Age (y); Median (range)	ALP cut-off (IU/L)	Enneking stage	HR (95% CI)	Follow-up (m); Median (range)
Aparicio et al., 1999 [25]	Spain	33	17 (12–42)	115	II	1.26 (0.42–3.74)	96 (60–156)
Foukas et al., 2002 [26]	UK	45	18 (6–48)	NA	IIB	3.44 (1.52–7.79)	68 (28–88)
Ford et al., 2004 [27]	UK	350	NS (<40)	NA	II	1.66 (1.09–2.51)	NA
Bramer et al., 2005 [28]	UK	89	NA	NA	II	1.49 (0.72–3.06)	NA
Mialou et al., 2005 [29]	France	60	13.5 (2–19)	500	IIIB	2.2 (1.2–4.1)	NA
Yalçın et al., 2008 [30]	Turkey	55	13 (7–17)	NA	II-III	1.1 (0.5–2.41)	NA
Chou et al., 2009 [31]	USA	91	NA	NA	III	3.16 (1.77–5.36)	89 (1–141)
Kim et al., 2009 [32]	Korea	67	15.7 (3.8–644)	NA	II	1.37 (0.54–3.45)	59.9
Wu et al., 2009 [33]	Taiwan ROC	91	20.2 (5–84)	A^†	II-III	2.52 (1.32–4.75)	58.2 (2–233)
Yao et al., 2009 [34]	China	57	16 (6–70)	136	II-III	3.45 (1.4–8.46)	32.5 (10–52)
Hagleitner et al., 2011 [35]	Netherlands	94	17.8 (4.5–39.5)	NA	II-III	1.66 (0.88–3.11)	67.2 (28.8–360)
Ferrari et al., 2012 [36]	Italy	209	14 (4–39)	A	II	1.69 (0.98–2.9)	76 (31–115)
Han et al., 2012 [37]	China	177	23.2 (5–57)	A	II	1.80 (1.28–2.51)	87 (8–144)
Durnali et al., 2013 [38]	Turkey	211	20 (13–74)	A	II-III	1.75 (1.23–2.5)	30.5 (0.5–213)
Min et al., 2013 [39]	China	333	19 (5–78)	NA	II-III	1.73 (1.28–2.33)	NA (1–100)
Hung et al., 2015 [40]	Taiwan ROC	69	13.5 (3.8–17.7)	150	II-III	3.08 (1.05–9.08)	51.6 (18–111.6)
Berner et al., 2015 [41]	Norway	301	NA	A	II-III	1.64 (1.22–2.19)	NA

NA: not available, A: available (see the footnotes for details), HR: hazard ratio, CI: confidence interval, y: year(s), and m: month(s).
: 2 times of upper limit normal level.
: ALP cut-off: 2–10 y 100–350 IU/L; 10–13 y female 110–400 IU/L; 13–15 y male 125–500 IU/L; 20–50 y 25–100 IU/L; other childhood age 73–300 IU/L.
§: ALP cut-off: >18 y 150 IU/L; <18 y 110 IU/L.
Δ: ALP cut-off: 0–17 y 400 IU/L; >17 y 105 IU/L.