Table 1 Characteristics of the 177 primary lung cancer patients enrolled in this study.

*Average age(range)

77.3 ± 7.0 (55-92)

*Gender (male: female)

132:45

**Range of follow-up period (median)

11-99 (27)

Tumor diameter (average ± standard deviation)

8-55 mm(30.0 ± 9.1)

central tumors: peripheral tumors

22:155

Method of radiotherapy (48Gy/4fr:60Gr/10fr:70Gr/10fr)

75:37:65