Table 3.

OS and CSS of lung cancer with distant metastasis to bone, brain, liver, and lung with or without radiotherapy after PSM^a

Metastatic site	n	OS (95% CI)bmo	P c	CSS (95% CI)bmo	P c
Braind
No RT	2253	5.6 (5.2‐6.0)	<0.001	6.3 (5.8‐6.9)	<0.001
RT	2253	7.5 (7.0‐8.0)		8.1 (7.6‐8.7)
Boned
No RT	5515	8.2 (7.9‐8.6)	0.027	9.0 (8.6‐9.3)	0.134
RT	5515	8.2 (7.9‐8.5)		8.8 (8.4‐9.1)
Liverd
No RT	2113	6.5 (6.0‐7.0)	0.175	7.0 (6.5‐7.6)	0.399
RT	2113	6.4 (6.0‐6.8)		6.8 (6.4‐7.2)
Lungd
No RT	3479	9.4 (9.0‐9.9)	0.040	10.4 (9.9‐10.9)	0.055
RT	3479	10.0 (9.5‐10.4)		10.6 (10.1‐11.1)
All sitese
No RT	11 025	9.7 (9.5‐10.0)	0.328	10.7 (10.4‐11.0)	0.648
RT	11 025	9.5 (9.2‐9.7)		10.1 (9.9‐10.4)
≥2 sitesf
No RT	3874	6.7 (6.3‐7.0)	<0.001	7.4 (7.0‐7.7)	0.012
RT	3874	7.1 (6.8‐7.4)		7.5 (7.2‐7.9)

n, number of cases/controls; OS, overall survival; CSS, cancer‐specific survival; CI, confidence interval; PSM, propensity score matching; RT, radiotherapy.

^aPSM were done in each subgroup using variables including: age, gender, race, marital, histological types, grade, T stage, N stage, chemotherapy, surgery, and radiotherapy.

^bDerived from Kaplan‐Meier survival analysis.

^cDerived from log‐rank test statistics.

^dBone, brain, liver, and lung are four sites of distant metastasis at diagnose SEER provided.

^eAll sites: With one or more metastatic sites in bone, brain, liver, and lung.

^f≥2 sites: With two or more metastatic sites in bone, brain, liver, and lung.