Table 1.

Characteristics of studies in this meta-analysis

Study name	Region	Study type	Sample size				Stage	Therapy
			Total	GPS 0	GPS 1	GPS 2
Miyazaki et al. (2015)	Japan	Retrospective	97	65	32		I	Surg
Kishi et al. (2015)	Japan	Retrospective	165	100	65		I	SBRT
Kawashima et al. (2015)	Japan	Retrospective	1043	897	107	39	I–III	Surg
Jiang and Lu (2015)	China	Prospective	138	95	32	11	III–IV	Chemo
Grose et al. (2015)	UK	Prospective	120	50	49	21	I–III	Surg/RT/Chemo
Tomita et al. (2014)	Japan	Retrospective	312	264	31	17	I–III	Surg
Pinato et al. (2014)	UK	Prospective	220	131	39	29	I–III	Surg
MacKenzie et al. (2014)	UK	Retrospective	97	–	–	–	I–III	Surgery/RT
Rinehart et al. (2013)	USA	Prospective	51	9	32	10	IV	Chemo
Meek et al. (2010)	UK	Retrospective	56	19	31	6	Inoperable II–IV	RT/Chemo
Forrest et al. (2004)	UK	Prospective	109	27	69	13	Inoperable III–IV	Chemo
Leung et al. (2012)	UK	Prospective	261	59	163	39	Inoperable III–IV	RT/Chemo

Surg surgery, SBRT stereotactic body radiation therapy, RT radiotherapy, Chemo chemotherapy