Table 1 Demographic characteristics of patients in CIRT and segmentectomy groups before treatment

Mean age + SD (year-old)

75 ± 7.2

65 ± 7.2

0.000660

Mean Body Mass Index ± SD (kg/m²)

22 + 2 1

23 + 3.3

0.366

Gender: Male/female

13/1

22/26

0.00179

ECOG Performance Status: 0/1

10/4

40/8

0.321

Charlson comorbidity index

0.593

 Low: 0

3

18

 Medium: 1–2

6

17

 High: 34

4

12

 Very high: ≥ 5

1

1

Mean maximum tumor size ± SD (mm)

25 + 8.6

17 + 4.7

0.00543

Mean maximum consolidation size + SD (mm)

4.7 ± 5.5

4.2 ± 3.6

0.738

Mean consolidation/tumor size ± SD

0.17 ± 0.16

0.23 + 0.19

0.245

Clinical stage (UICC8)

0.773

 TlisNOMO

2

12

 UmiNOMO

6

19

 TlaNOMO

5

15

 TlbNOMO

0

1

 TIcNOMO

1

1

Histology

N/A

 Adenocarcinoma

14

48

 Non-adenocarcinoma

0

0

Spirometry

 Mean %FVC ± SD (%)

91 ± 19

106 + 13

0.0173

 Mean %FEV1 ± SD (%)

103 + 27

103 + 14

0.965

 Mean FEV1% ± SD (%)

77 + 15

77 ± 6.3

0.996

Mean smoking Index + SD (pack-year)

38 + 41

19 + 26

0.146