Table 4: Main characteristics and results of the eligible studies for evaluation of metastasis development for nonmetastatic patients.

Study
(author/year)
CountryNumber of patientsAge (y)ALP cut-off (IU/L)
Enneking stageRR (95% CI)Follow-up (m)
Median (range)

Smeland et al., 2003 [44]Norway104NAAII1.66 (0.68–4.07)83 (42–124)
Han et al., 2012 [37]China17723.2 (5–57)AII2.17 (0.97–4.84)87 (8–144)
Kim et al., 2014 [45]Korea91NAAIIB2.03 (1.04–3.97)NA

NA: not available, A: available (see the footnotes for details), RR: relative risk, y: year(s), and m: month(s).
: 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.
: ALP cut-off: >14 y 115.5 IU/L; <14 y 300 IU/L.