1. Summary of included studies.

Study ID		Number of Patients			Radiotherapy
First Author	Year	Platinum group	Non‐platinum group	Total
Baka	2008	141	139	280	PCI, TRT
Chahinian	1989	105	103	208	PCI
Creech	1982	21	19	40	‐
de Jong	2007	101	102	203	‐
Eagan	1981	31	31	62	TRT
Evans	1987	145	144	289	PCI, TRT
Farris	1993	56	57	113	PCI, TRT
Fukuoka	1986	35	34	69	TRT
Fukuoka	1991	97	97	194	TRT
Gatzemeier	1994	171	173	344	‐
Goodman	1990	194	194	388	PCI, TRT
Greco	2005	60	60	120	PCI
Havemann	1987	150	152	302	PCI, TRT
Jones	1993	54	50	104	PCI, TRT
Kanitz	1992	59	52	111	‐
Lyss	2002	12	13	25	PCI
Postmus	1992	60	63	123	PCI
Postmus	1996	70	73	143	‐
Quoix	2005	41	41	82	‐
Roth	1992	148	146	294	PCI
Sculier	1990	95	106	201	PCI
Sculier	1993	107	108	215	PCI, TRT
Sekine	2014	30	32	62	‐
Smith	1991	47	48	95	PCI
Souhami	1997	80	75	155	‐
Sundstrom	2002	218	218	436	PCI, TRT
Urban	1999a	191	203	394	PCI, TRT
Urban	1999b	229	228	457	PCI, TRT
Veronesi	1994	70	66	136	PCI, TRT
Wampler	1991	85	85	170	‐
White	2001	60	59	119	PCI, TRT
Wolf	1987	73	68	141	PCI, TRT
Total: 32	‐	3036	3039	6075	‐

PCI ‐ Prophylactic Cranial Irradiation

TRT ‐ Thoracic Radiotherapy