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

Table 2

Main characteristics and results of the eligible studies for evaluation of event-free survival.

Study; (author/year)	Country	Number of patients	Age (y)	ALP cut-off (IU/L)	Enneking stage	HR (95% CI)	Follow-up (m); Median (range)
Mialou et al., 2005 [29]	France	48	13.5 (2–19)	500	IIIB	2.7 (1.5–4.8)	NA
Lee et al., 2007 [42]	Korea	45	<15	A^†	II	4.55 (1.22–16.99)	54 (6–153)
Yalçın et al., 2008 [30]	Turkey	55	13 (7–17)	NA	II-III	1.11 (0.54–2.31)	NA
Kim et al., 2009 [32]	Korea	67	15.7 (3.8–64.4)	NA	II	1.84 (0.84–4.07)	59.9
Chou et al., 2009 [31]	USA	91	NA	NA	III	2.83 (1.68–4.79)	89 (1–141)
Ferrari et al., 2012 [36]	Italy	209	14 (4–39)	A	II	1.71 (1.09–2.67)	76 (31–115)
Berner et al., 2015 [41]	Norway	237	NA	A^Δ	II-III	1.78 (1.26–2.52)	NA

NA: not available, A: available (see the footnotes for details), HR: hazard ratio, CI: confidence interval, y: year(s), and m: month(s).
: ALP cut-off: 2–10 y 420 IU/L; 10-11 y 560 IU/L; 12–15 y male 495 IU/L; 12-13 y female 420 IU/L; 14-15 y female 230 IU/L.
: ALP cut-off: 2–10 y 350 IU/L; 10–13 y female 400 IU/L; 13–15 y male 500 IU/L; 20–50 y 100 IU/L; other childhood age 300 IU/L.
Δ: ALP cut-off: 0–17 y 400 IU/L; >17 y 105 IU/L.