Loss of heterozygosity for chromosomes 16q in Wilms tumors predicts outcomes: A meta-analysis

Table 1 Characteristics of included studies

Ref.	Country	Patients	Age	Follow-up	Method to Detect LOH 16q
Spreafico et al[27], 2013	Italy	Nonanaplastic unilateral WT of stages I to IV	Median 40 months, range 1 to 172 months	Mean = 73 months, range 35 to 97 months	Microsatellite markers
Grundy et al[6], 2005	Australia, New Zealand, Switzerland, and the Netherlands	1724 patients younger than 16 years at diagnosis with specific WT	< 16 yr	4 yr	PCR
Chagtai et al[35], 2016	26 countries: 24 in Europe, 1 in Australia, 1 in South America	586 patients with WT of stages I to IV	Range 6 months to 18 years	M = 68 months	Multiplex Ligation-ependent Probe Amplification
Messahel et al[7], 2009	United Kingdom	426 patients with favorable-histology WT	Not known	4 yr	Microsatellite markers
Grundy et al[2], 1994	United States	204 patients with histology WT	< 17 yr	M = 1.3 yr (LOH group) or 1.4 yr (control group)	PCR
Grundy et al[3], 1998	United Kingdom	40 patients with sporadic WT	Not known	≥ 7 yr	PCR
Klamt et al[4], 1998	Germany	73 patients with WT	Mean = 3.48 yr	Not known	PCR
Skotnicka-Klonowicz et al[36], 2000	Poland	58 patients with WT	M = 39 months; range = 2 d to 13 yr	M = 42 months; range = 14–139 months	PCR
Zhang et al[37], 2002	China	30 patients with WT	M = 38 months; range = 2 months to 13 yr	Not known	PCR
Kullendorff et al[38], 2003	Sweden	39 patients with WT	M = 4.2 yr, range 5 months to 15 yr	Range 7 to 160 months	Not known
Fernandez et al[22], 2017	United States, Canada, New Zealand and Israel	110 patients with very low risk WT (defined as stage I favorable histology WT with nephrectomy weight < 550 g and age at diagnosis < 2 yr)	11.5 months: 0.1 to 23 months	M = 80 months: 5 to 97 months	Multiplex Ligation-ependent Probe Amplification

LOH: Loss of heterozygosity; WT: Wilms’ tumor; M: Median.

Table 2 Quality assessment of the included studies

Ref.	Selection	Comparability	Outcome	NOS score	Quality
Spreafico et al[27], 2013	4	1	1	6	Moderate
Grundy et al[6], 2005	4	1	1	5	Moderate
Chagtai et al[35], 2016	3	2	2	6	High
Messahel et al[7], 2009	3	1	2	5	High
Grundy et al[2], 1994	3	2	2	6	High
Grundy et al[3], 1998	3	1	2	6	High
Klamt et al[4], 1998	3	2	2	5	Moderate
Skotnicka-Klonowicz et al[36], 2000	4	2	1	5	Moderate
Zhang et al[37], 2002	3	2	2	6	High
Kullendorff et al[38], 2003	3	3	1	5	Moderate
Fernandez et al[22], 2017	3	1	2	6	High