Adjuvant chemotherapy for isolated resectable colorectal lung metastasis: A retrospective study using inverse probability treatment weighting propensity analysis

Table 3 Univariable Cox proportional hazards model for overall survival after inverse probability of treatment-weighting

Factors		HR (univariable)
Gender	M
	F	0.8556 (0.3201-2.287, P = 0.756)
Age at primary cancer	≤ 60 years
	> 60 years	1.1914 (0.4402-3.224, P = 0.730)
Smoking history	No
	Yes	1.07988 (0.3514-3.319, P = 0.893)
Age lung surgery	≤ 60 years
	> 60 years	0.6498 (0.2495-1.692, P = 0.377)
Surgical approach for PM	Open
	VATS	0.5052 (0.1863-1.37, P = 0.18)
Type of resection	Lobectomy
	Sublobar resection	0.6032 (0.2248-1.619, P = 0.065)
Lymph node dissection	No
	Yes	1.2383 (0.4682-2.728, P = 0.667)
Positive LN at PM	No
	Yes	0.9268 (0.1181-7.271, P = 0.942)
Adjuvant chemotherapy	No
	Yes	0.4204 (0.1632-1.083, P = 0.0726)
Primary tumor location	Left colon
	Right colon	0.4590 (0.1093-1.928, P = 0.288)
	Rectum	0.6267 (0.2328-1.687, P = 0.355)
CEA levels	≤ 5 ng/mL
	> 5 ng/mL	2.7261 (1.075-6.913, P = 0.0347)
Number of metastatic lesions	1
	> 1	2.1928 (0.8496-5.66, P = 0.105)
Bilateral pulmonary nodules	No
	Yes	2.478 (0.9703-6.329, P = 0.0578)
Tumor size (cm)	≤ 2 cm
	> 2 cm	0.7971 (0.2961-2.146, P = 0.653)
Prior extra-thoracic metastasis	No
	Yes	4.627 (1.01-21.2, P = 0.0485)

CRC: Colorectal cancer; CEA: Carcinoembryonic antigen; PM: Pulmonary metastases; VATS: Video-assisted thoracoscopic surgery; HR: Hazard ratio; M: Male; F: Female.