Table 3. Selected lung cancer studies analysing the FGFR1 gene status in lung cancer patients using FISH technique.

Author	Number of NSCLC analysed	Tissue technique	FGFR1 amplification (%)	FGFR1 amplification and histology	ISH probe used	Definition of FGFR1amplification	Tumour stages included in the study	Overall survival whole patient cohort	Overall survival early stage (I and II)
Weiss et al, 2010	153	TMA (two to three cores)	22	only SCC analysed	FGFR1 locus: BAC Reference: none	FGFR1 >9 signals	IA, IB, IIB, IIIA, IIIB (available from n=15)	No data	No data
Heist et al, 2012	226	Whole tissue sections	16	only SCC analysed	FGFR1 locus: BAC Reference: commercially available CEP8	Ratio FGFR1/CEP⩾2.2	IA; IB; IIA; IIB; IIIA; IIIB; IV	No statistical difference between FGFR1-amplified and non-amplified	No difference between FGFR1-amplified and non-amplified (n=155)
Kohler et al, 2012	260	TMA (one core)	6.5	10.5% SCC, 4.7% AC	Commercially available dual-colour FISH probe	FGFR1⩾4 signals	T1; T2; T3; T4; N0; >N0	No impact	No data
Schildhaus et al, 2012	407	Whole tissue sections	17.3	20% SCC and 1x ASCC and 1x LC	Commercially available dual-colour FISH probe	FGFR1/CEN8 ratio ⩾2.0 or average number of FGFR1 signals per tumour cell nucleus is ⩾6 or the percentage of tumour cells containing ⩾15 FGFR1 signals or large clusters in ⩾10% or the percentage of tumour cells containing ⩾5 FGFR1 signals in ⩾50%	No data	No impact (preliminary data)	No data
Zhang et al, 2012	127	Whole tissue sections	8.7	12.5% SCC, 7% AC	FGFR1 locus: BAC Reference: commercially available CEP8	Ratio FGFR1/CEP⩾2.0 or ⩾10%gene cluster	I, II, III, IV	No data	No data
Craddock et al, 2013	121	TMA (three cores)	18.2	only SCC analysed	Commercially available dual-colour FISH probe	>5 Copies of FGFR1	IA, IB, IIA, IIB, IIIA, IIIB, IV	No significant difference	No data
Kim et al, 2013	262	TMA (three cores)	13	Only SCC analysed	Commercially available dual-colour FISH probe	FGFR1 signal ⩾9 (high-level amplification)	I; II; IIIA; IIIB	High-level FGFR1 amplified shorter survival and DFS	No data
Tran et al, 2013	264	TMA (three to six cores)	14	21.8% SCC, 20.5%LC, 5.2% AC	Commercially available dual-colour FISH probe	According to Schildhaus et al, 2012	IA, IB, IIA, IIB, III	FGFR1-amplified tumours better prognosis	No data
Current study	329	TMA (one core)	12.5	20.7% SCC, 2.2% AC, 13% LC	Commercially available dual-colour FISH probe	FGFR1 to CEP8 signal ratio of ⩾2.0.	IA, IB, IIA, IIB	Worse OS and worse DFS	Difference between FGFR1-amlified and non-amplified tumours (n=329)

Abbreviations: AC=adenocarcinoma; BAC=bacterial artificial chromosome; FISH=fluorescent in situ hybridisation; LC=large cell carcinoma; NSCLC=non-small cell lung carcinoma; SCC=squamous cell carcinoma; TMA=tissue microarray.