Radiofrequency ablation with or without capecitabine maintenance therapy for lung oligometastases from colorectal cancer

Table 1 Clinical characteristics of patients enrolled, n (%)

Variables	Total (n = 247)	Only RFA (n = 99)	Combined (n = 148)	P value
Sex				0.509
Female	96 (38.9)	36 (36.4)	60 (40.5)
Male	151 (61.1)	63 (63.6)	88 (59.5)
Age, median (IQR) (years)	58.0 (48.0, 66.0)	58.0 (53.0, 66.5)	58.5 (48.0, 66.0)	0.633
KRAS				0.846
Wild-type	154 (62.3)	61 (61.6)	93 (62.8)
Mutated	93 (37.7)	38 (38.4)	55 (37.2)
CA19-9				0.029
< 27 U/mL	216 (87.4)	81 (81.8)	135 (91.2)
≥ 27 U/mL	31 (12.6)	18 (18.2)	13 (8.8)
CEA				0.267
< 5 ng/mL	188 (76.1)	79 (79.8)	109 (73.6)
≥ 5 ng/mL	59 (23.9)	20 (20.2)	39 (26.4)
Location				0.658
Left	129 (52.2)	50 (50.5)	79 (53.4)
Right	118 (47.8)	49 (49.5)	69 (46.6)
Number of lesions				0.006
1	171 (69.2)	78 (78.8)	93 (62.8)
2	67 (27.1)	21 (21.2)	46 (31.1)
3	9 (3.6)	0 (0)	9 (6.1)
Lesion diameter, median (IQR)	1.0 (0.8, 1.5)	1.0 (0.8, 1.5)	1.0 (0.8, 1.4)	0.521
Distance between the lesion and the mediastinum or great vessels				0.392
≤ 1 cm	124 (50.2)	53 (53.5)	71 (48)
> 1 cm	123 (49.8)	46 (46.5)	77 (52)
Distance between the lesion and the pleural surface				0.495
≤ 1 cm	81 (32.8)	30 (30.3)	51 (34.5)
> 1 cm	166 (67.2)	69 (69.7)	97 (65.5)
Primary lesion pathology				0.807
Rectum	159 (64.4)	66 (66.7)	93 (62.8)
Left half colon	52 (21.2)	19 (19.2)	33 (22.3)
Right half colon	36 (14.6)	14 (14.1)	22 (14.9)
Primary tumor (T) staging				0.8
1	4 (1.6)	2 (2)	2 (1.4)
2	25 (10.1)	10 (10.1)	15 (10.1)
3	128 (51.8)	48 (48.5)	80 (54.1)
4	90 (36.4)	39 (39.4)	51 (34.5)
Neural invasion				0.308
None	168 (68.0)	71 (71.7)	97 (65.5)
Exist	79 (32.0)	28 (28.3)	51 (34.5)
Lymphovascular invasion				0.974
None	150 (60.7)	60 (60.6)	90 (60.8)
Exist	97 (39.3)	39 (39.4)	58 (39.2)
Synchronous or metachronous				0.217
Metachronous	139 (56.3)	51 (51.5)	88 (59.5)
Synchronous	108 (43.7)	48 (48.5)	60 (40.5)
Pneumothorax				0.694
None	194 (78.5)	79 (79.8)	115 (77.7)
Grade 1	42 (17.0)	18 (18.2)	24 (16.2)
Grade 2	11 (4.5)	5 (5.1)	6 (4.1)
Grade 3	3 (1.2)	1 (1.0)	2 (1.4)
Alveolar hemorrhage				0.643
None	203 (82.2)	80 (80.8)	123 (83.1)
Grade 1	39 (15.8)	17 (17.2)	22 (14.9)
Grade 2	5 (2.0)	2 (2.0)	3 (2.0)

IQR: Interquartile range; CEA: Carcinoembryonic antigen; CA19-9: Carbohydrate antigen 19-9; RFA: Radiofrequency ablation; Combined: Radiofrequency ablation plus capecitabine; Only RFA: Radiofrequency ablation alone.