Table 1.

Main characteristics of studies included in the meta-analysis

Author	Year	Country	No.	Follow-up (median)	stage	Cut-off value	Detection method	IGF1R positive ratio (%)	Quality score (%)	Results
Gately K.	2013	Ireland	184	65.09	I-III	Score ≥ 200	IHC	53.80	70.78	N*
Zhang XY	2013	China	178	60	I-III	Score ≥ 20	IHC	71.35	67.65	N*
Xu C.	2013	China	200	52.6	I-IV	Score ≥ 4	IHC	78.00	55.59	P
Ludovini V.	2013	Italy	125	48.9	I-III	> 10%	IHC, FISH	36.80	61.67	N*
Yamamoto T.	2012	Japan	78	48.87	I-III	Score ≥ 200	IHC	52.56	64.37	P
Tsuta K	2012	Japan	379	58.6	I-IV	> 10%	IHC	41.42	54.26	N*
Kim YH	2012	Japan	68	30	III-IV	> 10%	IHC	54.41	63.18	N
Kim JS	2012	Houston	459	49.2	I-III	> 10%	IHC	39.22	55.74	P
Kikuchi R.	2011	Japan	238	56.5	I-IV	Score ≥ 2	IHC	55.04	60.21	N
Nakagawa M.	2011	Japan	182	68.7	I-IV	> 10%	IHC	23.62	74.64	P
Dziadziuszko R.	2010	Poland	189	63.6	I-IV	Score ≥ 2	IHC, qRT-PCR	45.56	65.71	N
Ning XH	2010	China	39	35	I-IV	Score ≥ 1	IHC	53.84	54.89	N*
Cappuzzo F.	2009	Italy	369	60	I-III	score ≥ 100	IHC	76.4	58.01	N*
Chang MH	2009	Korea	194	60	I-IV	Score ≥ 1	IHC	81.44	68.99	N*
Gong YX	2009	Manhattan	264	60	I-IV	> 10%	IHC	39.39	48.30	N*
Lee CY	2008	Korea	71	60	I-IV	Score ≥ 1	IHC	12.68	57.82	N*
Cappuzzo F.	2006	Italy	77	24	III-IV	Score ≥ 2	IHC	38.96	62.29	N

No.: Patients number; IHC: Immunohistochemistry; FISH: Fluorescence in situ hybridization; IGF1R: Insulin-like growth factor-1 receptor; qRT-PCR: Quantitative reverse transcription polymerase chain reaction. P: Studies identitying IGF1R positive expression as significant poor prognosis factor. N: Studies reporting IGF1R positive expression as good prognosis factor.

^*Studies reporting IGF1R positive expression as non-significant association with prognosis.