Long-Term Survival of Patients with Metastatic Non-Small-Cell Lung Cancer over Five Decades

Table 1

Univariate and multivariate analysis of variables associated with overall survival in metastatic lung cancer patients, 1973–2015, Cox model. The multivariate analysis incorporated following variables: age, sex, race, marital status, histology, grade, year of diagnosis, treatment modality (of note regarding treatment, for each modality the database doses not differentiate between ‘treatment not given’ and ‘unknown whether given’), and income (relating to county median income, 2010, in 10,000$). Patients with missing data for any one of these covariates were excluded from the multivariate analysis.

Variable^a	Univariate analysis			Multivariate analysis
	HR	95% C.I.	value	HR	95% C.I.	value
Age	1.013	(1.013, 1.013)	<0.001	1.007	(1.006, 1.008)	<0.001
Sex (female vs. male)	0.852	(0.839, 0.852)	<0.001	0.840	(0.825, 0.849)	<0.001
Race
White	1.000 (comparator group)
Black	0.989	(0.978, 1.001)	0.063	0.979	(0.960, 0.999)	0.045
Am. Indian/Alaska	1.011	(0.952, 1.074)	NS (0.72)	1.143	(0.986, 1.325)	0.076
Asian/Pacific Islander	0.753	(0.742, 0.765)	<0.001	0.832	(0.808, 0.856)	<0.001
Unknown/other	0.602	(0.524, 0.693)	<0.001	0.638	(0.475, 0.858)	0.003
Married	0.880	(0.873, 0.887)	<0.001	0.906	(0.893, 0.919)	<0.001
Histology
Lung carcinoma NOS	1.000 (comparator group)
Adenocarcinoma	0.736	(0.729, 0.742)	<0.001	0.860	(0.844, 0.875)	<0.001
Squamous cell ca.	0.866	(0.856, 0.875)	<0.001	0.910	(0.892, 0.929)	<0.001
Small cell carcinoma	0.858	(0.849, 0.866)	<0.001	1.029	(1.008, 1.05)	0.007
Grade
Well diff.	1.000 (comparator group)
Moderately diff.	1.173	(1.138, 1.209)	<0.001	1.190	(1.149, 1.233)	<0.001
Poorly diff.	1.512	(1.470, 1.554)	<0.001	1.484	(1.436, 1.535)	<0.001
Undifferentiated	1.781	(1.725, 1.840)	<0.001	1.484	(1.425, 1.545)	<0.001
Year of diagnosis
1973–9	1.000 (comparator group)
1980–9	0.948	(0.928, 0.968)	<0.001	0.952	(0.918, 0.987)	0.008
1990–9	0.906	(0.889, 0.924)	<0.001	0.935	(0.903, 0.969)	<0.001
2000–9	0.773	(0.759, 0.787)	<0.001	0.821	(0.793, 0.850)	<0.001
2010–5	0.663	(0.651, 0.676)	<0.001	0.739	(0.712, 0.766)	<0.001
Treatment
No treatment	1.00 (comparator group)
Chemotherapy only	0.423	(0.418, 0.428)	<0.001	0.488	(0.478, 0.498)	<0.001
Radiotherapy only	0.766	(0.759, 0.774)	<0.001	0.772	(0.758, 0.787)	<0.001
Chemo + radio	0.445	(0.440, 0.449)	<0.001	0.517	(0.507, 0.527)	<0.001
Income^b	0.977	(0.974, 0.980)	<0.001	0.979	(0.974, 0.985)	<0.001

HR: hazard ratio. CI: confidence interval. Am: American. NOS: non-other specified. Ca: carcinoma. Diff: differentiated. Chemo: chemotherapy. Radio: radiotherapy. ^aMissing values: grade: 207,149 patients. Marital status: 12,727 patients. Treatment: 10,881 patients. Age: 3 patients. Income: 73,156 patients. ^b2010 yearly median county income (per 10,000 dollars).